From git at git.haskell.org  Thu Mar  1 19:07:49 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Thu,  1 Mar 2018 19:07:49 +0000 (UTC)
Subject: [commit: ghc] master: Revert "Better stats for T5837" (2756117)
Message-ID: <20180301190749.EE7113A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/2756117bd26c2cb70d3f51954a88b7d7bdf3d3f2/ghc

>---------------------------------------------------------------

commit 2756117bd26c2cb70d3f51954a88b7d7bdf3d3f2
Author: Ben Gamari <ben at smart-cactus.org>
Date:   Thu Mar 1 14:06:04 2018 -0500

    Revert "Better stats for T5837"
    
    This reverts commit d675a354e8db67d87d1f257c3d1d2bf2d58c2b3f.


>---------------------------------------------------------------

2756117bd26c2cb70d3f51954a88b7d7bdf3d3f2
 testsuite/tests/perf/compiler/all.T | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/testsuite/tests/perf/compiler/all.T b/testsuite/tests/perf/compiler/all.T
index 4c2462c..1a2413a 100644
--- a/testsuite/tests/perf/compiler/all.T
+++ b/testsuite/tests/perf/compiler/all.T
@@ -665,7 +665,7 @@ test('T5837',
              # 2017-04-21                       54985248 (x64/Windows) - Unknown
              # 2017-12-24                       54793816 (x64/Windows) - Unknown
 
-           (wordsize(64), 51294232, 7)])
+           (wordsize(64), 55813608, 7)])
              # sample: 3926235424 (amd64/Linux, 15/2/2012)
              # 2012-10-02 81879216
              # 2012-09-20 87254264 amd64/Linux
@@ -704,7 +704,6 @@ test('T5837',
              # 2017-09-06 56782344  amd64/Linux Drift manifest in unrelated LLVM patch
              # 2017-10-24 52089424  amd64/linux Fix space leak in BinIface.getSymbolTable
              # 2018-02-19 55813608  amd64/Linux Unknown
-             # 2018-02-27 51294232  amd64/Linux Better still, I'm not sure why
       ],
       compile, ['-freduction-depth=50'])
 


From git at git.haskell.org  Thu Mar  1 23:55:20 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Thu,  1 Mar 2018 23:55:20 +0000 (UTC)
Subject: [commit: ghc] wip/T2893: Add superclasses to quantified constraints
 (910dfcf)
Message-ID: <20180301235520.A819D3A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/T2893
Link       : http://ghc.haskell.org/trac/ghc/changeset/910dfcfeadc4f132e887bc4adf5ac2e17a29d99b/ghc

>---------------------------------------------------------------

commit 910dfcfeadc4f132e887bc4adf5ac2e17a29d99b
Author: Simon Peyton Jones <simonpj at microsoft.com>
Date:   Thu Mar 1 23:32:29 2018 +0000

    Add superclasses to quantified constraints
    
    This patch adds suppport for superclasses to quantified constraints.
    For example (contrived):
    
      f :: (forall a. Ord a => Ord (m a)) => m a -> m a -> Bool
      f x y = x==y
    
    Here we need (Eq (m a)); but the quantifed constraint deals only
    with Ord.  But we can make it work by using its superclass.
    
    This behaviour finally delivers on the promise of comment:30 of
    Trac #9123: we can write an implication constraint that solves
    the problem of higher-kinded roles.  Test
    quantified-constraints/T8123 demonstrates this in action.


>---------------------------------------------------------------

910dfcfeadc4f132e887bc4adf5ac2e17a29d99b
 compiler/basicTypes/Id.hs                          |   2 +-
 compiler/typecheck/Inst.hs                         |   4 +-
 compiler/typecheck/TcCanonical.hs                  | 180 +++++++++++++--------
 compiler/typecheck/TcErrors.hs                     |   4 +-
 compiler/typecheck/TcEvTerm.hs                     |   5 +-
 compiler/typecheck/TcEvidence.hs                   |  74 +++++----
 compiler/typecheck/TcHsSyn.hs                      |  23 ++-
 compiler/typecheck/TcInstDcls.hs                   |   2 +-
 compiler/typecheck/TcInteract.hs                   |  61 +++----
 compiler/typecheck/TcMType.hs                      |   6 +-
 compiler/typecheck/TcPatSyn.hs                     |   7 +-
 compiler/typecheck/TcPluginM.hs                    |   2 +-
 compiler/typecheck/TcRnTypes.hs                    |  62 +++++--
 compiler/typecheck/TcSMonad.hs                     | 119 +++++++-------
 compiler/typecheck/TcSimplify.hs                   |   2 +-
 compiler/typecheck/TcType.hs                       |   2 +-
 compiler/types/Class.hs                            |  54 ++++---
 compiler/types/Kind.hs                             |   2 +
 testsuite/tests/quantified-constraints/T2893c.hs   |  15 ++
 .../quantified-constraints/{T2893b.hs => T9123.hs} |   2 +-
 testsuite/tests/quantified-constraints/T9123a.hs   |  26 +++
 testsuite/tests/quantified-constraints/all.T       |   5 +
 22 files changed, 403 insertions(+), 256 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc 910dfcfeadc4f132e887bc4adf5ac2e17a29d99b

From git at git.haskell.org  Fri Mar  2 05:02:55 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Fri,  2 Mar 2018 05:02:55 +0000 (UTC)
Subject: [commit: ghc] wip/docker-ghcci: Directory change (0c248bf)
Message-ID: <20180302050255.51E793A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/docker-ghcci
Link       : http://ghc.haskell.org/trac/ghc/changeset/0c248bfb640aefa3fb4b8fdd740688b5ba66cea9/ghc

>---------------------------------------------------------------

commit 0c248bfb640aefa3fb4b8fdd740688b5ba66cea9
Author: David Feuer <David.Feuer at gmail.com>
Date:   Fri Mar 2 00:02:27 2018 -0500

    Directory change


>---------------------------------------------------------------

0c248bfb640aefa3fb4b8fdd740688b5ba66cea9
 .circleci/images/x86_64-linux/Dockerfile | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/.circleci/images/x86_64-linux/Dockerfile b/.circleci/images/x86_64-linux/Dockerfile
index 4630ba2..3eefa1b 100644
--- a/.circleci/images/x86_64-linux/Dockerfile
+++ b/.circleci/images/x86_64-linux/Dockerfile
@@ -8,6 +8,6 @@ RUN apt-get install -qy openssh-client
 
 RUN apt-get install -qy git make automake autoconf gcc perl python3 texinfo xz-utils lbzip2 patch
 
-RUN ln -s $HOME/.cabal/bin/HsColour /usr/local/bin/HsColour
+RUN ln -s /home/ghc/.cabal/bin/HsColour /usr/local/bin/HsColour
 
 USER ghc


From git at git.haskell.org  Fri Mar  2 06:13:56 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Fri,  2 Mar 2018 06:13:56 +0000 (UTC)
Subject: [commit: ghc] wip/docker-ghcci: Install more earlier (3553bf2)
Message-ID: <20180302061356.B1C273A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/docker-ghcci
Link       : http://ghc.haskell.org/trac/ghc/changeset/3553bf2b8d5b544cd6a37ddbb65e71beebaa26e0/ghc

>---------------------------------------------------------------

commit 3553bf2b8d5b544cd6a37ddbb65e71beebaa26e0
Author: David Feuer <David.Feuer at gmail.com>
Date:   Fri Mar 2 00:45:49 2018 -0500

    Install more earlier


>---------------------------------------------------------------

3553bf2b8d5b544cd6a37ddbb65e71beebaa26e0
 .circleci/config.yml                     | 2 --
 .circleci/images/x86_64-linux/Dockerfile | 1 +
 2 files changed, 1 insertion(+), 2 deletions(-)

diff --git a/.circleci/config.yml b/.circleci/config.yml
index 8507e23..fb3697e 100644
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -181,8 +181,6 @@ jobs:
       - run:
           name: Install LLVM
           command: |
-            apt-get update
-            apt-get install -y curl xz-utils
             curl http://releases.llvm.org/5.0.0/clang+llvm-5.0.0-x86_64-linux-gnu-debian8.tar.xz | tar -xJC ..
             # See https://discuss.circleci.com/t/how-to-add-a-path-to-path-in-circle-2-0/11554/3
             echo "export PATH=`pwd`/../clang+llvm-5.0.0-x86_64-linux-gnu-debian8/bin:\$PATH" >> $BASH_ENV
diff --git a/.circleci/images/x86_64-linux/Dockerfile b/.circleci/images/x86_64-linux/Dockerfile
index 3eefa1b..8584e4a 100644
--- a/.circleci/images/x86_64-linux/Dockerfile
+++ b/.circleci/images/x86_64-linux/Dockerfile
@@ -7,6 +7,7 @@ RUN apt-get update -qq
 RUN apt-get install -qy openssh-client
 
 RUN apt-get install -qy git make automake autoconf gcc perl python3 texinfo xz-utils lbzip2 patch
+RUN apt-get install -qy curl xz-utils
 
 RUN ln -s /home/ghc/.cabal/bin/HsColour /usr/local/bin/HsColour
 


From git at git.haskell.org  Fri Mar  2 06:22:14 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Fri,  2 Mar 2018 06:22:14 +0000 (UTC)
Subject: [commit: ghc] wip/docker-ghcci: Version number. (ed89d8e)
Message-ID: <20180302062214.99C893A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/docker-ghcci
Link       : http://ghc.haskell.org/trac/ghc/changeset/ed89d8eb8bda8851891c43941506a578c0653b09/ghc

>---------------------------------------------------------------

commit ed89d8eb8bda8851891c43941506a578c0653b09
Author: David Feuer <David.Feuer at gmail.com>
Date:   Fri Mar 2 01:19:09 2018 -0500

    Version number.


>---------------------------------------------------------------

ed89d8eb8bda8851891c43941506a578c0653b09
 .circleci/config.yml | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/.circleci/config.yml b/.circleci/config.yml
index fb3697e..cf06942 100644
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -86,7 +86,7 @@ jobs:
   "validate-x86_64-linux":
     resource_class: xlarge
     docker:
-      - image: dfeuer/ghcci:x86_64-linux-0.0.4
+      - image: dfeuer/ghcci:x86_64-linux-0.0.6
     environment:
       <<: *buildenv
     steps:
@@ -144,7 +144,7 @@ jobs:
   "validate-hadrian-x86_64-linux":
     resource_class: xlarge
     docker:
-      - image: dfeuer/ghcci:x86_64-linux-0.0.4
+      - image: dfeuer/ghcci:x86_64-linux-0.0.6
     environment:
       <<: *buildenv
     steps:
@@ -158,7 +158,7 @@ jobs:
   "validate-x86_64-linux-unreg":
     resource_class: xlarge
     docker:
-      - image: dfeuer/ghcci:x86_64-linux-0.0.4
+      - image: dfeuer/ghcci:x86_64-linux-0.0.6
     environment:
       <<: *buildenv
     steps:
@@ -173,7 +173,7 @@ jobs:
   "validate-x86_64-linux-llvm":
     resource_class: xlarge
     docker:
-      - image: dfeuer/ghcci:x86_64-linux-0.0.4
+      - image: dfeuer/ghcci:x86_64-linux-0.0.6
     environment:
       <<: *buildenv
       BUILD_FLAVOUR: perf-llvm


From git at git.haskell.org  Fri Mar  2 06:28:47 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Fri,  2 Mar 2018 06:28:47 +0000 (UTC)
Subject: [commit: ghc] wip/docker-ghcci: Add another llvm version (5964d8a)
Message-ID: <20180302062847.DDE683A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/docker-ghcci
Link       : http://ghc.haskell.org/trac/ghc/changeset/5964d8a1e6788fe0d3e367913b4254b3d5cb7022/ghc

>---------------------------------------------------------------

commit 5964d8a1e6788fe0d3e367913b4254b3d5cb7022
Author: David Feuer <David.Feuer at gmail.com>
Date:   Fri Mar 2 01:28:12 2018 -0500

    Add another llvm version
    
    Dunno if the paths will work out


>---------------------------------------------------------------

5964d8a1e6788fe0d3e367913b4254b3d5cb7022
 .circleci/config.yml | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/.circleci/config.yml b/.circleci/config.yml
index cf06942..79e8005 100644
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -181,9 +181,11 @@ jobs:
       - run:
           name: Install LLVM
           command: |
+            curl http://releases.llvm.org/3.9.0/clang+llvm-3.9.0-x86_64-linux-gnu-debian8.tar.xz | tar -xJC ..
             curl http://releases.llvm.org/5.0.0/clang+llvm-5.0.0-x86_64-linux-gnu-debian8.tar.xz | tar -xJC ..
             # See https://discuss.circleci.com/t/how-to-add-a-path-to-path-in-circle-2-0/11554/3
             echo "export PATH=`pwd`/../clang+llvm-5.0.0-x86_64-linux-gnu-debian8/bin:\$PATH" >> $BASH_ENV
+            echo "export PATH=`pwd`/../clang+llvm-3.9.0-x86_64-linux-gnu-debian8/bin:\$PATH" >> $BASH_ENV
       - run:
           name: Verify that llc works
           command: llc


From git at git.haskell.org  Fri Mar  2 06:53:20 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Fri,  2 Mar 2018 06:53:20 +0000 (UTC)
Subject: [commit: ghc] wip/docker-ghcci: Darwin Python installation (5177e14)
Message-ID: <20180302065320.25E1D3A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/docker-ghcci
Link       : http://ghc.haskell.org/trac/ghc/changeset/5177e14b47ccc4a27a38ff7108c1459c83d448ad/ghc

>---------------------------------------------------------------

commit 5177e14b47ccc4a27a38ff7108c1459c83d448ad
Author: David Feuer <David.Feuer at gmail.com>
Date:   Fri Mar 2 01:52:51 2018 -0500

    Darwin Python installation


>---------------------------------------------------------------

5177e14b47ccc4a27a38ff7108c1459c83d448ad
 .circleci/prepare-system.sh | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/.circleci/prepare-system.sh b/.circleci/prepare-system.sh
index 84fd513..9f9bb93 100755
--- a/.circleci/prepare-system.sh
+++ b/.circleci/prepare-system.sh
@@ -44,7 +44,8 @@ case "$(uname)" in
     if [[ -n ${TARGET:-} ]]; then
       fail "uname=$(uname) not supported for cross-compilation"
     fi
-    brew install ghc cabal-install python3 ncurses gmp
+    brew install ghc cabal-install ncurses gmp
+    brew upgrade python3
     cabal update
     cabal install --reinstall alex happy haddock hscolour --index-state=$hackage_index_state
     # put them on the $PATH, don't fail if already installed


From git at git.haskell.org  Fri Mar  2 12:42:24 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Fri,  2 Mar 2018 12:42:24 +0000 (UTC)
Subject: [commit: ghc] master: Cache the fingerprint of sOpt_P (b8f03bb)
Message-ID: <20180302124224.9FDF73A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/b8f03bbe16af7a09b494a33fbbe523ecd82f1a50/ghc

>---------------------------------------------------------------

commit b8f03bbe16af7a09b494a33fbbe523ecd82f1a50
Author: Bartosz Nitka <niteria at gmail.com>
Date:   Thu Feb 22 06:44:59 2018 -0800

    Cache the fingerprint of sOpt_P
    
    Before this change we would compute a hash of
    all the command line -optP flags once per file.
    With a lot of files and many -optP flags, that's a lot
    of repeated work.
    
    I added a new Note that explains the approach and rationale.
    
    Test Plan: new test
    
    Reviewers: simonmar, simonpj, bgamari
    
    Reviewed By: simonpj
    
    Subscribers: rwbarton, thomie, carter
    
    GHC Trac Issues: #14697
    
    Differential Revision: https://phabricator.haskell.org/D4445


>---------------------------------------------------------------

b8f03bbe16af7a09b494a33fbbe523ecd82f1a50
 compiler/iface/FlagChecker.hs           | 37 ++++++++++++++++++++++++++++++++-
 compiler/main/DynFlags.hs               | 19 ++++++++++++++++-
 compiler/main/SysTools.hs               |  2 ++
 testsuite/tests/perf/compiler/all.T     | 13 ++++++++++++
 testsuite/tests/perf/compiler/genT14697 | 17 +++++++++++++++
 5 files changed, 86 insertions(+), 2 deletions(-)

diff --git a/compiler/iface/FlagChecker.hs b/compiler/iface/FlagChecker.hs
index 1fc597b..2ef369a 100644
--- a/compiler/iface/FlagChecker.hs
+++ b/compiler/iface/FlagChecker.hs
@@ -47,8 +47,10 @@ fingerprintDynFlags dflags at DynFlags{..} this_mod nameio =
 
         -- -I, -D and -U flags affect CPP
         cpp = ( map normalise $ flattenIncludes includePaths
-              , opt_P dflags ++ picPOpts dflags)
             -- normalise: eliminate spurious differences due to "./foo" vs "foo"
+              , picPOpts dflags
+              , opt_P_signature dflags)
+            -- See Note [Repeated -optP hashing]
 
         -- Note [path flags and recompilation]
         paths = [ hcSuf ]
@@ -144,3 +146,36 @@ executable when some of its components differ in these ways.
 The way we accomplish this is to leave the optimization and HPC
 options out of the flag hash, hashing them separately.
 -}
+
+{- Note [Repeated -optP hashing]
+   ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+We invoke fingerprintDynFlags for each compiled module to include
+the hash of relevant DynFlags in the resulting interface file.
+-optP (preprocessor) flags are part of that hash.
+-optP flags can come from multiple places:
+
+  1. -optP flags directly passed on command line.
+  2. -optP flags implied by other flags. Eg. -DPROFILING implied by -prof.
+  3. -optP flags added with {-# OPTIONS -optP-D__F__ #-} in a file.
+
+When compiling many modules at once with many -optP command line arguments
+the work of hashing -optP flags would be repeated. This can get expensive
+and as noted on #14697 it can take 7% of time and 14% of allocations on
+a real codebase.
+
+The obvious solution is to cache the hash of -optP flags per GHC invocation.
+However, one has to be careful there, as the flags that were added in 3. way
+have to be accounted for.
+
+The current strategy is as follows:
+
+  1. Lazily compute the hash of sOpt_p in sOpt_P_fingerprint whenever sOpt_p
+     is modified. This serves dual purpose. It ensures correctness for when
+     we add per file -optP flags and lets us save work for when we don't.
+  2. When computing the fingerprint in fingerprintDynFlags use the cached
+     value *and* fingerprint the additional implied (see 2. above) -optP flags.
+     This is relatively cheap and saves the headache of fingerprinting all
+     the -optP flags and tracking all the places that could invalidate the
+     cache.
+-}
diff --git a/compiler/main/DynFlags.hs b/compiler/main/DynFlags.hs
index b7720dd..074b7e3 100644
--- a/compiler/main/DynFlags.hs
+++ b/compiler/main/DynFlags.hs
@@ -89,6 +89,7 @@ module DynFlags (
         pgm_L, pgm_P, pgm_F, pgm_c, pgm_s, pgm_a, pgm_l, pgm_dll, pgm_T,
         pgm_windres, pgm_libtool, pgm_ar, pgm_ranlib, pgm_lo, pgm_lc,
         pgm_lcc, pgm_i, opt_L, opt_P, opt_F, opt_c, opt_a, opt_l, opt_i,
+        opt_P_signature,
         opt_windres, opt_lo, opt_lc, opt_lcc,
 
         -- ** Manipulating DynFlags
@@ -195,6 +196,7 @@ import qualified Pretty
 import SrcLoc
 import BasicTypes       ( IntWithInf, treatZeroAsInf )
 import FastString
+import Fingerprint
 import Outputable
 import Foreign.C        ( CInt(..) )
 import System.IO.Unsafe ( unsafeDupablePerformIO )
@@ -1169,6 +1171,8 @@ data Settings = Settings {
   -- options for particular phases
   sOpt_L                 :: [String],
   sOpt_P                 :: [String],
+  sOpt_P_fingerprint     :: Fingerprint, -- cached Fingerprint of sOpt_P
+                                         -- See Note [Repeated -optP hashing]
   sOpt_F                 :: [String],
   sOpt_c                 :: [String],
   sOpt_a                 :: [String],
@@ -1241,6 +1245,14 @@ opt_L dflags = sOpt_L (settings dflags)
 opt_P                 :: DynFlags -> [String]
 opt_P dflags = concatMap (wayOptP (targetPlatform dflags)) (ways dflags)
             ++ sOpt_P (settings dflags)
+
+-- This function packages everything that's needed to fingerprint opt_P
+-- flags. See Note [Repeated -optP hashing].
+opt_P_signature       :: DynFlags -> ([String], Fingerprint)
+opt_P_signature dflags =
+  ( concatMap (wayOptP (targetPlatform dflags)) (ways dflags)
+  , sOpt_P_fingerprint (settings dflags))
+
 opt_F                 :: DynFlags -> [String]
 opt_F dflags = sOpt_F (settings dflags)
 opt_c                 :: DynFlags -> [String]
@@ -2434,7 +2446,12 @@ setDumpPrefixForce f d = d { dumpPrefixForce = f}
 setPgmP   f = let (pgm:args) = words f in alterSettings (\s -> s { sPgm_P   = (pgm, map Option args)})
 addOptl   f = alterSettings (\s -> s { sOpt_l   = f : sOpt_l s})
 addOptc   f = alterSettings (\s -> s { sOpt_c   = f : sOpt_c s})
-addOptP   f = alterSettings (\s -> s { sOpt_P   = f : sOpt_P s})
+addOptP   f = alterSettings (\s -> s { sOpt_P   = f : sOpt_P s
+                                     , sOpt_P_fingerprint = fingerprintStrings (f : sOpt_P s)
+                                     })
+                                     -- See Note [Repeated -optP hashing]
+  where
+  fingerprintStrings ss = fingerprintFingerprints $ map fingerprintString ss
 
 
 setDepMakefile :: FilePath -> DynFlags -> DynFlags
diff --git a/compiler/main/SysTools.hs b/compiler/main/SysTools.hs
index 4c16286..35935ca 100644
--- a/compiler/main/SysTools.hs
+++ b/compiler/main/SysTools.hs
@@ -48,6 +48,7 @@ import ErrUtils
 import Platform
 import Util
 import DynFlags
+import Fingerprint
 
 import System.FilePath
 import System.IO
@@ -302,6 +303,7 @@ initSysTools mbMinusB
                     sPgm_i   = iserv_prog,
                     sOpt_L       = [],
                     sOpt_P       = [],
+                    sOpt_P_fingerprint = fingerprint0,
                     sOpt_F       = [],
                     sOpt_c       = [],
                     sOpt_a       = [],
diff --git a/testsuite/tests/perf/compiler/all.T b/testsuite/tests/perf/compiler/all.T
index 1a2413a..2afa595 100644
--- a/testsuite/tests/perf/compiler/all.T
+++ b/testsuite/tests/perf/compiler/all.T
@@ -1212,6 +1212,19 @@ test('T13719',
      multimod_compile,
      ['T13719', '-v0'])
 
+test('T14697',
+     [ compiler_stats_num_field('bytes allocated',
+          [(wordsize(64), 337290376, 10),
+          # initial:    635573784
+          # 2018-02-23: 337290376 Cache the fingerprint of sOpt_P
+          ]),
+       pre_cmd('./genT14697'),
+       extra_files(['genT14697']),
+       extra_hc_opts('$(cat T14697-flags)'), # 10k -optP arguments
+     ],
+     multimod_compile,
+     ['T14697', '-v0'])
+
 test('Naperian',
      [ reqlib('vector'),
        only_ways(['optasm']),
diff --git a/testsuite/tests/perf/compiler/genT14697 b/testsuite/tests/perf/compiler/genT14697
new file mode 100755
index 0000000..e3fe4f4
--- /dev/null
+++ b/testsuite/tests/perf/compiler/genT14697
@@ -0,0 +1,17 @@
+#!/bin/bash
+SIZE=100
+ROOT=T14697
+# Generates 100 empty modules and T14697 that imports them all
+# It (along with the command line arguments) reproduces a problem where
+# -optP command line flags would be hashed once per file
+for i in $(seq -w 1 $SIZE); do
+  echo "module A$i where" > A$i.hs
+done
+
+echo "module ${ROOT} where" > $ROOT.hs
+for i in $(seq -w 1 $SIZE); do
+  echo "import A$i" >> $ROOT.hs;
+done
+
+# generate flags
+echo -optP-D__F{1..10000}__ > T14697-flags


From git at git.haskell.org  Fri Mar  2 16:17:04 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Fri,  2 Mar 2018 16:17:04 +0000 (UTC)
Subject: [commit: ghc] master: rts: Note functions which must take
 all_tasks_mutex. (8dab89b)
Message-ID: <20180302161704.734993A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/8dab89b4d148d322cd7ac8c374be3342ab017297/ghc

>---------------------------------------------------------------

commit 8dab89b4d148d322cd7ac8c374be3342ab017297
Author: Ben Gamari <ben at smart-cactus.org>
Date:   Fri Mar 2 11:13:14 2018 -0500

    rts: Note functions which must take all_tasks_mutex.


>---------------------------------------------------------------

8dab89b4d148d322cd7ac8c374be3342ab017297
 rts/Capability.c | 3 +++
 rts/Schedule.c   | 1 +
 rts/Task.c       | 2 ++
 3 files changed, 6 insertions(+)

diff --git a/rts/Capability.c b/rts/Capability.c
index 03b2a86..f9141ee 100644
--- a/rts/Capability.c
+++ b/rts/Capability.c
@@ -498,6 +498,9 @@ giveCapabilityToTask (Capability *cap USED_IF_DEBUG, Task *task)
  *
  * The current Task (cap->task) releases the Capability.  The Capability is
  * marked free, and if there is any work to do, an appropriate Task is woken up.
+ *
+ * N.B. May need to take all_tasks_mutex.
+ *
  * ------------------------------------------------------------------------- */
 
 #if defined(THREADED_RTS)
diff --git a/rts/Schedule.c b/rts/Schedule.c
index cdb9659..b8306df 100644
--- a/rts/Schedule.c
+++ b/rts/Schedule.c
@@ -2005,6 +2005,7 @@ forkProcess(HsStablePtr *entry
         RELEASE_LOCK(&task->lock);
 
 #if defined(THREADED_RTS)
+        /* N.B. releaseCapability_ below may need to take all_tasks_mutex */
         RELEASE_LOCK(&all_tasks_mutex);
 #endif
 
diff --git a/rts/Task.c b/rts/Task.c
index fc928d5..758ae10 100644
--- a/rts/Task.c
+++ b/rts/Task.c
@@ -199,6 +199,7 @@ freeTask (Task *task)
     stgFree(task);
 }
 
+/* Must take all_tasks_mutex */
 static Task*
 newTask (bool worker)
 {
@@ -443,6 +444,7 @@ workerStart(Task *task)
     scheduleWorker(cap,task);
 }
 
+/* N.B. must take all_tasks_mutex */
 void
 startWorkerTask (Capability *cap)
 {


From git at git.haskell.org  Fri Mar  2 16:17:07 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Fri,  2 Mar 2018 16:17:07 +0000 (UTC)
Subject: [commit: ghc] master: forkProcess: fix task mutex release order
 (e261b85)
Message-ID: <20180302161707.6B65B3A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/e261b8523eb547b93b8b9e194bc2566350e7cc60/ghc

>---------------------------------------------------------------

commit e261b8523eb547b93b8b9e194bc2566350e7cc60
Author: Ömer Sinan Ağacan <omeragacan at gmail.com>
Date:   Fri Mar 2 11:15:03 2018 -0500

    forkProcess: fix task mutex release order
    
    `all_tasks_mutex` should be released before calling `releaseCapability_`
    in the parent process as `releaseCapability_` spawns worker tasks in
    some cases.
    
    Reviewers: bgamari, erikd, simonmar
    
    Subscribers: rwbarton, thomie, carter
    
    GHC Trac Issues: #14538
    
    Differential Revision: https://phabricator.haskell.org/D4460


>---------------------------------------------------------------

e261b8523eb547b93b8b9e194bc2566350e7cc60
 rts/Schedule.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/rts/Schedule.c b/rts/Schedule.c
index f1363e4..cdb9659 100644
--- a/rts/Schedule.c
+++ b/rts/Schedule.c
@@ -2004,15 +2004,15 @@ forkProcess(HsStablePtr *entry
         RELEASE_LOCK(&stable_mutex);
         RELEASE_LOCK(&task->lock);
 
+#if defined(THREADED_RTS)
+        RELEASE_LOCK(&all_tasks_mutex);
+#endif
+
         for (i=0; i < n_capabilities; i++) {
             releaseCapability_(capabilities[i],false);
             RELEASE_LOCK(&capabilities[i]->lock);
         }
 
-#if defined(THREADED_RTS)
-        RELEASE_LOCK(&all_tasks_mutex);
-#endif
-
         boundTaskExiting(task);
 
         // just return the pid


From git at git.haskell.org  Fri Mar  2 17:34:45 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Fri,  2 Mar 2018 17:34:45 +0000 (UTC)
Subject: [commit: ghc] wip/T2893: Add missing import (62a16bd)
Message-ID: <20180302173445.258413A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/T2893
Link       : http://ghc.haskell.org/trac/ghc/changeset/62a16bdcdc27158ad545c744eec52cb481203323/ghc

>---------------------------------------------------------------

commit 62a16bdcdc27158ad545c744eec52cb481203323
Author: Simon Peyton Jones <simonpj at microsoft.com>
Date:   Fri Mar 2 17:34:34 2018 +0000

    Add missing import


>---------------------------------------------------------------

62a16bdcdc27158ad545c744eec52cb481203323
 compiler/typecheck/TcPluginM.hs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/compiler/typecheck/TcPluginM.hs b/compiler/typecheck/TcPluginM.hs
index 086ac26..a112003 100644
--- a/compiler/typecheck/TcPluginM.hs
+++ b/compiler/typecheck/TcPluginM.hs
@@ -69,7 +69,7 @@ import TcRnMonad  ( TcGblEnv, TcLclEnv, Ct, CtLoc, TcPluginM
                   , liftIO, traceTc )
 import TcMType    ( TcTyVar, TcType )
 import TcEnv      ( TcTyThing )
-import TcEvidence ( TcCoercion, CoercionHole
+import TcEvidence ( TcCoercion, CoercionHole, EvTerm(..)
                   , EvExpr, EvBind, mkGivenEvBind )
 import TcRnTypes  ( CtEvidence(..) )
 import Var        ( EvVar )


From git at git.haskell.org  Fri Mar  2 18:48:56 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Fri,  2 Mar 2018 18:48:56 +0000 (UTC)
Subject: [commit: ghc] master: Only load plugins once (f8e3cd3)
Message-ID: <20180302184856.BCD7A3A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/f8e3cd3b160d20dbd18d490b7babe43153bb3287/ghc

>---------------------------------------------------------------

commit f8e3cd3b160d20dbd18d490b7babe43153bb3287
Author: Matthew Pickering <matthewtpickering at gmail.com>
Date:   Fri Mar 2 18:45:47 2018 +0000

    Only load plugins once
    
    Summary: This is part of D4342 which is worthwhile to merge on its own.
    
    Reviewers: nboldi, bgamari
    
    Reviewed By: bgamari
    
    Subscribers: rwbarton, thomie, carter
    
    Differential Revision: https://phabricator.haskell.org/D4410
    
    Co-authored-by: Boldizsar Nemeth <nboldi at elte.hu>


>---------------------------------------------------------------

f8e3cd3b160d20dbd18d490b7babe43153bb3287
 compiler/main/DynFlags.hs        |  8 ++++++++
 compiler/main/DynamicLoading.hs  | 36 ++++++++++++++++++++++++++++++------
 compiler/main/HscMain.hs         | 10 +++++++---
 compiler/main/Plugins.hs         | 37 +++++++++++++++++++++++++++++++++----
 compiler/main/Plugins.hs-boot    |  9 +++++++++
 compiler/simplCore/SimplCore.hs  | 34 +++++++---------------------------
 compiler/typecheck/TcRnDriver.hs | 21 +++++----------------
 7 files changed, 99 insertions(+), 56 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc f8e3cd3b160d20dbd18d490b7babe43153bb3287

From git at git.haskell.org  Fri Mar  2 19:11:54 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Fri,  2 Mar 2018 19:11:54 +0000 (UTC)
Subject: [commit: ghc] master: Make cost centre symbol names deterministic.
 (d8e47a2)
Message-ID: <20180302191154.99B7E3A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/d8e47a2ea89dbce647b06132ec10c39a2de67437/ghc

>---------------------------------------------------------------

commit d8e47a2ea89dbce647b06132ec10c39a2de67437
Author: Shea Levy <shea at shealevy.com>
Date:   Fri Mar 2 12:59:06 2018 -0500

    Make cost centre symbol names deterministic.
    
    Previously, non-CAF cost centre symbol names contained a unique,
    leading to non-deterministic object files which, among other issues,
    can lead to an inconsistency causing linking failure when using cached
    builds sourced from multiple machines, such as with nix. Now, each
    cost centre symbol is annotated with the type of cost centre it
    is (CAF, expression annotation, declaration annotation, or HPC) and,
    when a single module has multiple cost centres with the same name and
    type, a 0-based index.
    
    Reviewers: bgamari, simonmar
    
    Reviewed By: bgamari
    
    Subscribers: niteria, simonmar, RyanGlScott, osa1, rwbarton, thomie, carter
    
    GHC Trac Issues: #4012, #12935
    
    Differential Revision: https://phabricator.haskell.org/D4388


>---------------------------------------------------------------

d8e47a2ea89dbce647b06132ec10c39a2de67437
 compiler/deSugar/Coverage.hs          |  21 +++---
 compiler/deSugar/DsExpr.hs            |   5 +-
 compiler/deSugar/DsMonad.hs           |  14 ++--
 compiler/ghc.cabal.in                 |   1 +
 compiler/profiling/CostCentre.hs      | 131 +++++++++++++++++++++-------------
 compiler/profiling/CostCentreState.hs |  36 ++++++++++
 compiler/stgSyn/CoreToStg.hs          |   2 +-
 compiler/typecheck/TcBinds.hs         |  16 +++--
 compiler/typecheck/TcRnMonad.hs       |  29 +++++++-
 compiler/typecheck/TcRnTypes.hs       |   8 ++-
 10 files changed, 188 insertions(+), 75 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc d8e47a2ea89dbce647b06132ec10c39a2de67437

From git at git.haskell.org  Fri Mar  2 21:07:37 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Fri,  2 Mar 2018 21:07:37 +0000 (UTC)
Subject: [commit: ghc] master: Move Data.Functor.Contravariant from the
 contravariant package to base. (8c7a155)
Message-ID: <20180302210737.581403A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/8c7a1551fcd004c37f4ccd99c7c10395179519f1/ghc

>---------------------------------------------------------------

commit 8c7a1551fcd004c37f4ccd99c7c10395179519f1
Author: Andrew Martin <andrew.thaddeus at gmail.com>
Date:   Fri Mar 2 14:14:13 2018 -0500

    Move Data.Functor.Contravariant from the contravariant package to base.
    
    Move Data.Functor.Contravariant from the contravariant package to base.
    Since base is the bottom of the dependency hierarchy, several instances
    have been removed. They will need to be added to the following packages:
    transformers, StateVar, and possibly tagged. There may not actually have
    been any types from tagged that previous had instanced provided by this
    module though, since it may have only been used for Data.Proxy. Additionally,
    all CPP has been removed. Derived Typeable instances have been removed
    (since Typeable is now automatically derived for everything). The language
    extension Safe is still used, although it is unclear to ATM whether or not
    it is necessary.
    
    This resolves trac issue #14767.
    
    Test Plan: validate
    
    Reviewers: RyanGlScott, ekmett, hvr, bgamari
    
    Reviewed By: RyanGlScott
    
    Subscribers: rwbarton, thomie, ekmett, carter, RyanGlScott
    
    GHC Trac Issues: #14767
    
    Differential Revision: https://phabricator.haskell.org/D4399


>---------------------------------------------------------------

8c7a1551fcd004c37f4ccd99c7c10395179519f1
 docs/users_guide/8.6.1-notes.rst             |   7 +-
 libraries/base/Data/Functor/Contravariant.hs | 295 +++++++++++++++++++++++++++
 libraries/base/base.cabal                    |   1 +
 libraries/base/changelog.md                  |   2 +
 4 files changed, 304 insertions(+), 1 deletion(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc 8c7a1551fcd004c37f4ccd99c7c10395179519f1

From git at git.haskell.org  Fri Mar  2 21:07:41 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Fri,  2 Mar 2018 21:07:41 +0000 (UTC)
Subject: [commit: ghc] master: Improve exhaustive checking for guards in
 pattern bindings and MultiIf. (e8e9f6a)
Message-ID: <20180302210741.1999B3A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/e8e9f6a7a6d857efe6e3b2aec0c4964f9a8fa09a/ghc

>---------------------------------------------------------------

commit e8e9f6a7a6d857efe6e3b2aec0c4964f9a8fa09a
Author: HE, Tao <sighingnow at gmail.com>
Date:   Fri Mar 2 14:16:24 2018 -0500

    Improve exhaustive checking for guards in pattern bindings and MultiIf.
    
    Previously we didn't do exhaustive checking on MultiIf expressions
    and guards in pattern bindings.
    
    We can construct the `LMatch` directly from GRHSs or [LHsExpr]
    (MultiIf's alts) then feed it to checkMatches, without construct the
    MatchGroup and using function `matchWrapper`.
    
    Signed-off-by: HE, Tao <sighingnow at gmail.com>
    
    Test Plan: make test TEST="T14773a T14773b"
    
    Reviewers: bgamari, RyanGlScott, simonpj
    
    Reviewed By: bgamari, simonpj
    
    Subscribers: rwbarton, thomie, carter
    
    GHC Trac Issues: #14773
    
    Differential Revision: https://phabricator.haskell.org/D4400


>---------------------------------------------------------------

e8e9f6a7a6d857efe6e3b2aec0c4964f9a8fa09a
 compiler/deSugar/Check.hs                          | 24 +++++++++++++++---
 compiler/deSugar/DsBinds.hs                        |  2 ++
 compiler/deSugar/DsExpr.hs                         |  3 +++
 compiler/deSugar/DsGRHSs.hs                        |  3 +--
 compiler/hsSyn/HsExpr.hs                           | 29 ++++++++++++++--------
 docs/users_guide/8.6.1-notes.rst                   | 16 ++++++++++++
 testsuite/tests/deSugar/should_compile/T14773a.hs  | 10 ++++++++
 .../tests/deSugar/should_compile/T14773a.stderr    |  5 ++++
 testsuite/tests/deSugar/should_compile/T14773b.hs  |  8 ++++++
 .../tests/deSugar/should_compile/T14773b.stderr    |  5 ++++
 testsuite/tests/deSugar/should_compile/all.T       |  2 ++
 11 files changed, 91 insertions(+), 16 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc e8e9f6a7a6d857efe6e3b2aec0c4964f9a8fa09a

From git at git.haskell.org  Fri Mar  2 21:07:44 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Fri,  2 Mar 2018 21:07:44 +0000 (UTC)
Subject: [commit: ghc] master: Add regression test for #12790 (125d151)
Message-ID: <20180302210744.44B123A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/125d15181c7ac8d8fbaa43f799f9e3876dc2f57b/ghc

>---------------------------------------------------------------

commit 125d15181c7ac8d8fbaa43f799f9e3876dc2f57b
Author: Ryan Scott <ryan.gl.scott at gmail.com>
Date:   Fri Mar 2 14:17:52 2018 -0500

    Add regression test for #12790
    
    Test Plan: make test TEST=T12790
    
    Reviewers: bgamari, mpickering
    
    Reviewed By: mpickering
    
    Subscribers: mpickering, dfeuer, rwbarton, thomie, carter
    
    GHC Trac Issues: #12790
    
    Differential Revision: https://phabricator.haskell.org/D4412


>---------------------------------------------------------------

125d15181c7ac8d8fbaa43f799f9e3876dc2f57b
 testsuite/tests/profiling/should_compile/T12790.hs | 48 ++++++++++++++++++++++
 testsuite/tests/profiling/should_compile/all.T     |  1 +
 2 files changed, 49 insertions(+)

diff --git a/testsuite/tests/profiling/should_compile/T12790.hs b/testsuite/tests/profiling/should_compile/T12790.hs
new file mode 100644
index 0000000..3c3f7d4
--- /dev/null
+++ b/testsuite/tests/profiling/should_compile/T12790.hs
@@ -0,0 +1,48 @@
+module T12790 (list) where
+
+import Data.Foldable (asum)
+import Text.ParserCombinators.Parsec (Parser, sepBy, try)
+
+data Expr
+  = Var Fixity String
+  | App Expr Expr
+
+data Fixity = Pref | Inf
+
+cons, nil :: Expr
+cons = Var Inf  ":"
+nil  = Var Pref "[]"
+
+brackets :: Parser a -> Parser a
+brackets = undefined
+
+symbol :: String -> Parser String
+symbol = undefined
+
+list :: Parser Expr
+list = asum (map (try . brackets) plist) where
+  plist = [
+    foldr (\e1 e2 -> cons `App` e1 `App` e2) nil `fmap`
+      (myParser False `sepBy` symbol ","),
+    do e <- myParser False
+       _ <- symbol ".."
+       return $ Var Pref "enumFrom" `App` e,
+    do e  <- myParser False
+       _  <- symbol ","
+       e' <- myParser False
+       _  <- symbol ".."
+       return $ Var Pref "enumFromThen" `App` e `App` e',
+    do e  <- myParser False
+       _  <- symbol ".."
+       e' <- myParser False
+       return $ Var Pref "enumFromTo" `App` e `App` e',
+    do e   <- myParser False
+       _   <- symbol ","
+       e'  <- myParser False
+       _   <- symbol ".."
+       e'' <- myParser False
+       return $ Var Pref "enumFromThenTo" `App` e `App` e' `App` e''
+    ]
+
+myParser :: Bool -> Parser Expr
+myParser = undefined
diff --git a/testsuite/tests/profiling/should_compile/all.T b/testsuite/tests/profiling/should_compile/all.T
index 155206a..1ebcb07 100644
--- a/testsuite/tests/profiling/should_compile/all.T
+++ b/testsuite/tests/profiling/should_compile/all.T
@@ -5,3 +5,4 @@ test('prof002', [only_ways(['normal']), req_profiling], compile_and_run, ['-prof
 
 test('T2410', [only_ways(['normal']), req_profiling], compile, ['-O2 -prof -fprof-cafs'])
 test('T5889', [only_ways(['normal']), req_profiling, extra_files(['T5889/A.hs', 'T5889/B.hs'])], multimod_compile, ['A B', '-O -prof -fno-prof-count-entries -v0'])
+test('T12790', [only_ways(['normal']), req_profiling], compile, ['-O -prof'])


From git at git.haskell.org  Fri Mar  2 21:07:47 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Fri,  2 Mar 2018 21:07:47 +0000 (UTC)
Subject: [commit: ghc] master: Fix #14817 by not double-printing data family
 instance kind signatures (aef2b42)
Message-ID: <20180302210747.C8CEA3A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/aef2b429072e3d3bbdbcb9e4082a0d86ba329d9e/ghc

>---------------------------------------------------------------

commit aef2b429072e3d3bbdbcb9e4082a0d86ba329d9e
Author: Ryan Scott <ryan.gl.scott at gmail.com>
Date:   Fri Mar 2 14:18:15 2018 -0500

    Fix #14817 by not double-printing data family instance kind signatures
    
    Within `pprDataFamInstDecl`, we were invoking `pprFamInstLHS` to
    pretty-print a data family instance header, and we were passing `Just` a
    kind signature to `pprFamInstLHS` to make it pretty-print the kind
    signature alongside it (this is a consequence of commit
    d1ef223cfebd23c25489a4b0c67fbaa2f91c1ec6). But this is silly, because
    then invoke `pp_data_defn`, which //also// pretty-prints the kind
    signature, resulting in the kind signature being printed twice by
    mistake.
    
    This fix is simple—pass `Nothing` to `pprFamInstLHS` instead.
    
    Test Plan: make test TEST=T14817
    
    Reviewers: alanz, bgamari, mpickering
    
    Reviewed By: mpickering
    
    Subscribers: mpickering, rwbarton, thomie, carter
    
    GHC Trac Issues: #14817
    
    Differential Revision: https://phabricator.haskell.org/D4418


>---------------------------------------------------------------

aef2b429072e3d3bbdbcb9e4082a0d86ba329d9e
 compiler/hsSyn/HsDecls.hs        | 5 ++++-
 testsuite/tests/th/T14817.hs     | 6 ++++++
 testsuite/tests/th/T14817.stderr | 7 +++++++
 testsuite/tests/th/all.T         | 1 +
 4 files changed, 18 insertions(+), 1 deletion(-)

diff --git a/compiler/hsSyn/HsDecls.hs b/compiler/hsSyn/HsDecls.hs
index 8078582..475e31e 100644
--- a/compiler/hsSyn/HsDecls.hs
+++ b/compiler/hsSyn/HsDecls.hs
@@ -1555,7 +1555,10 @@ pprDataFamInstDecl top_lvl (DataFamInstDecl { dfid_eqn = HsIB { hsib_body =
   = pp_data_defn pp_hdr defn
   where
     pp_hdr ctxt = ppr_instance_keyword top_lvl
-              <+> pprFamInstLHS tycon pats fixity ctxt (dd_kindSig defn)
+              <+> pprFamInstLHS tycon pats fixity ctxt Nothing
+                    -- No need to pass an explicit kind signature to
+                    -- pprFamInstLHS here, since pp_data_defn already
+                    -- pretty-prints that. See #14817.
 
 pprDataFamInstFlavour :: DataFamInstDecl pass -> SDoc
 pprDataFamInstFlavour (DataFamInstDecl { dfid_eqn = HsIB { hsib_body =
diff --git a/testsuite/tests/th/T14817.hs b/testsuite/tests/th/T14817.hs
new file mode 100644
index 0000000..1019dec
--- /dev/null
+++ b/testsuite/tests/th/T14817.hs
@@ -0,0 +1,6 @@
+{-# LANGUAGE TemplateHaskell #-}
+{-# LANGUAGE TypeFamilies #-}
+module T14817 where
+
+$([d| data family Foo :: *
+      data instance Foo :: * |])
diff --git a/testsuite/tests/th/T14817.stderr b/testsuite/tests/th/T14817.stderr
new file mode 100644
index 0000000..7c63763
--- /dev/null
+++ b/testsuite/tests/th/T14817.stderr
@@ -0,0 +1,7 @@
+T14817.hs:(5,3)-(6,31): Splicing declarations
+    [d| data family Foo :: *
+        
+        data instance Foo :: * |]
+  ======>
+    data family Foo :: GHC.Types.Type
+    data instance Foo :: GHC.Types.Type
diff --git a/testsuite/tests/th/all.T b/testsuite/tests/th/all.T
index 4156716..7305800 100644
--- a/testsuite/tests/th/all.T
+++ b/testsuite/tests/th/all.T
@@ -399,3 +399,4 @@ test('T14204', normal, compile_fail, ['-v0'])
 test('T14060', normal, compile_and_run, ['-v0'])
 test('T14646', normal, compile, ['-v0 -ddump-splices -dsuppress-uniques'])
 test('T14681', normal, compile, ['-v0 -ddump-splices -dsuppress-uniques'])
+test('T14817', normal, compile, ['-v0 -ddump-splices -dsuppress-uniques'])


From git at git.haskell.org  Fri Mar  2 21:07:50 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Fri,  2 Mar 2018 21:07:50 +0000 (UTC)
Subject: [commit: ghc] master: DynFlags: Support British spelling of
 GeneralisedNewtypeDeriving (1773964)
Message-ID: <20180302210750.9FCEF3A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/17739645ce5a5d4b46b1de8d43e87b318a98ae6b/ghc

>---------------------------------------------------------------

commit 17739645ce5a5d4b46b1de8d43e87b318a98ae6b
Author: Ben Gamari <bgamari.foss at gmail.com>
Date:   Fri Mar 2 14:18:48 2018 -0500

    DynFlags: Support British spelling of GeneralisedNewtypeDeriving
    
    Reviewers: dfeuer
    
    Reviewed By: dfeuer
    
    Subscribers: dfeuer, rwbarton, thomie, carter
    
    GHC Trac Issues: #14819
    
    Differential Revision: https://phabricator.haskell.org/D4422


>---------------------------------------------------------------

17739645ce5a5d4b46b1de8d43e87b318a98ae6b
 compiler/main/DynFlags.hs         | 2 ++
 docs/users_guide/8.6.1-notes.rst  | 2 ++
 docs/users_guide/glasgow_exts.rst | 2 +-
 testsuite/tests/driver/T4437.hs   | 3 ++-
 4 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/compiler/main/DynFlags.hs b/compiler/main/DynFlags.hs
index 873ac3b..99a798e 100644
--- a/compiler/main/DynFlags.hs
+++ b/compiler/main/DynFlags.hs
@@ -4122,6 +4122,8 @@ xFlagsDeps = [
   flagSpec "GHCForeignImportPrim"             LangExt.GHCForeignImportPrim,
   flagSpec' "GeneralizedNewtypeDeriving"      LangExt.GeneralizedNewtypeDeriving
                                               setGenDeriving,
+  flagSpec' "GeneralisedNewtypeDeriving"      LangExt.GeneralizedNewtypeDeriving
+                                              setGenDeriving,
   flagSpec "ImplicitParams"                   LangExt.ImplicitParams,
   flagSpec "ImplicitPrelude"                  LangExt.ImplicitPrelude,
   flagSpec "ImpredicativeTypes"               LangExt.ImpredicativeTypes,
diff --git a/docs/users_guide/8.6.1-notes.rst b/docs/users_guide/8.6.1-notes.rst
index f5f2a5a..17617ac 100644
--- a/docs/users_guide/8.6.1-notes.rst
+++ b/docs/users_guide/8.6.1-notes.rst
@@ -54,6 +54,8 @@ Compiler
   calling the C compiler. Instead we use :ghc-flag:`-iquote` to only add it as
   an include path for `#include ""`. See :ghc-ticket:`14312`.
 
+- GHC now supports British spelling of :extension:`GeneralizedNewtypeDeriving`.
+
 Runtime system
 ~~~~~~~~~~~~~~
 
diff --git a/docs/users_guide/glasgow_exts.rst b/docs/users_guide/glasgow_exts.rst
index 439f4d2..40013f3 100644
--- a/docs/users_guide/glasgow_exts.rst
+++ b/docs/users_guide/glasgow_exts.rst
@@ -4586,7 +4586,7 @@ Generalised derived instances for newtypes
                GeneralizedNewtypeDeriving
     :shortdesc: Enable newtype deriving.
 
-    :since: 6.8.1
+    :since: 6.8.1. British spelling since 8.6.1.
 
     Enable GHC's cunning generalised deriving mechanism for ``newtype``\s
 
diff --git a/testsuite/tests/driver/T4437.hs b/testsuite/tests/driver/T4437.hs
index 6a46e52..d82e434 100644
--- a/testsuite/tests/driver/T4437.hs
+++ b/testsuite/tests/driver/T4437.hs
@@ -40,7 +40,8 @@ expectedGhcOnlyExtensions = ["RelaxedLayout",
                              "AlternativeLayoutRule",
                              "AlternativeLayoutRuleTransitional",
                              "EmptyDataDeriving",
-                             "NumericUnderscores"]
+                             "NumericUnderscores",
+                             "GeneralisedNewtypeDeriving"]
 
 expectedCabalOnlyExtensions :: [String]
 expectedCabalOnlyExtensions = ["Generics",


From git at git.haskell.org  Fri Mar  2 21:07:53 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Fri,  2 Mar 2018 21:07:53 +0000 (UTC)
Subject: [commit: ghc] master: Various Windows / Cross Compile to Windows
 fixes (4a0d0d8)
Message-ID: <20180302210753.B010F3A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/4a0d0d8062a204b867fc510c50e69a056ce7636f/ghc

>---------------------------------------------------------------

commit 4a0d0d8062a204b867fc510c50e69a056ce7636f
Author: Moritz Angermann <moritz.angermann at gmail.com>
Date:   Fri Mar 2 14:19:58 2018 -0500

    Various Windows / Cross Compile to Windows fixes
    
    - Adds quick-cross-ncg flavour.
    - Fix windows wchar with `_s` for mingw
    - Lookup windres, dllwrap and objdump
    - Fix type.
    
    Reviewers: bgamari, hvr, Phyx, erikd, simonmar
    
    Reviewed By: bgamari
    
    Subscribers: rwbarton, thomie, erikd, carter
    
    Differential Revision: https://phabricator.haskell.org/D4430


>---------------------------------------------------------------

4a0d0d8062a204b867fc510c50e69a056ce7636f
 configure.ac                      | 4 ++++
 libraries/base/cbits/Win32Utils.c | 2 ++
 rts/PathUtils.c                   | 5 +++++
 rts/win32/OSMem.c                 | 2 +-
 4 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/configure.ac b/configure.ac
index 216f43f..1d3effb 100644
--- a/configure.ac
+++ b/configure.ac
@@ -418,6 +418,10 @@ then
     AC_PATH_PROG([DllWrap],[dllwrap])
     AC_PATH_PROG([Windres],[windres])
     AC_PATH_PROG([Genlib],[genlib])
+else
+    AC_CHECK_TARGET_TOOL([Windres],[windres])
+    AC_CHECK_TARGET_TOOL([DllWrap],[dllwrap])
+    AC_CHECK_TARGET_TOOL([OBJDUMP],[objdump])
 fi
 
 DllWrapCmd="$DllWrap"
diff --git a/libraries/base/cbits/Win32Utils.c b/libraries/base/cbits/Win32Utils.c
index ce7ce97..b33db04 100644
--- a/libraries/base/cbits/Win32Utils.c
+++ b/libraries/base/cbits/Win32Utils.c
@@ -9,6 +9,8 @@
 #include "HsBase.h"
 #include <stdbool.h>
 #include <stdint.h>
+/* Using Secure APIs */
+#define MINGW_HAS_SECURE_API 1
 #include <wchar.h>
 #include <windows.h>
 
diff --git a/rts/PathUtils.c b/rts/PathUtils.c
index 1b0b729..def3f7e 100644
--- a/rts/PathUtils.c
+++ b/rts/PathUtils.c
@@ -7,6 +7,11 @@
 
 #include <libgen.h>
 #include <ctype.h>
+#if defined(mingw32_HOST_OS)
+/* Using Secure APIs */
+#define MINGW_HAS_SECURE_API 1
+#include <wchar.h>
+#endif
 
 pathchar* pathdup(pathchar *path)
 {
diff --git a/rts/win32/OSMem.c b/rts/win32/OSMem.c
index c67b95b..534cd15 100644
--- a/rts/win32/OSMem.c
+++ b/rts/win32/OSMem.c
@@ -458,7 +458,7 @@ void *osReserveHeapMemory (void *startAddress, W_ *len)
             sysErrorBelch(
                 "osReserveHeapMemory: VirtualAlloc MEM_RESERVE %llu bytes \
                 at address %p bytes failed",
-                len + MBLOCK_SIZE, startAddress);
+                *len + MBLOCK_SIZE, startAddress);
         }
         stg_exit(EXIT_FAILURE);
     }


From git at git.haskell.org  Fri Mar  2 21:54:01 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Fri,  2 Mar 2018 21:54:01 +0000 (UTC)
Subject: [commit: ghc] master: GHCi info: Use src file for cache invalidation
 (969e747)
Message-ID: <20180302215401.405633A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/969e747f67f57f7dd57c2e549d6a007505671158/ghc

>---------------------------------------------------------------

commit 969e747f67f57f7dd57c2e549d6a007505671158
Author: alexbiehl <alex.biehl at gmail.com>
Date:   Fri Mar 2 16:11:45 2018 -0500

    GHCi info: Use src file for cache invalidation
    
    Prior to this patch GHCi used the modification time of a module's object
    file to invalidate the info cache.
    
    We now look at the modification time of the source file, if present.
    
    This addresses part of
    https://ghc.haskell.org/trac/ghc/ticket/12706#comment:3.
    
    Reviewers: bgamari
    
    Reviewed By: bgamari
    
    Subscribers: lelf, alpmestan, rwbarton, thomie, carter
    
    GHC Trac Issues: #12706
    
    Differential Revision: https://phabricator.haskell.org/D4459


>---------------------------------------------------------------

969e747f67f57f7dd57c2e549d6a007505671158
 ghc/GHCi/UI/Info.hs | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/ghc/GHCi/UI/Info.hs b/ghc/GHCi/UI/Info.hs
index fd8749a..ad390dd 100644
--- a/ghc/GHCi/UI/Info.hs
+++ b/ghc/GHCi/UI/Info.hs
@@ -276,7 +276,9 @@ collectInfo ms loaded = do
     cacheInvalid name = case M.lookup name ms of
         Nothing -> return True
         Just mi -> do
-            let fp = ml_obj_file (ms_location (modinfoSummary mi))
+            let src_fp = ml_hs_file (ms_location (modinfoSummary mi))
+                obj_fp = ml_obj_file (ms_location (modinfoSummary mi))
+                fp     = fromMaybe obj_fp src_fp
                 last' = modinfoLastUpdate mi
             exists <- doesFileExist fp
             if exists


From git at git.haskell.org  Fri Mar  2 21:54:04 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Fri,  2 Mar 2018 21:54:04 +0000 (UTC)
Subject: [commit: ghc] master: Improve missing-home-modules warning formatting
 (6a7e159)
Message-ID: <20180302215404.1417A3A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/6a7e159ce25b432824f8757e0c768f2b2e2754df/ghc

>---------------------------------------------------------------

commit 6a7e159ce25b432824f8757e0c768f2b2e2754df
Author: Matthew Pickering <matthewtpickering at gmail.com>
Date:   Fri Mar 2 16:12:22 2018 -0500

    Improve missing-home-modules warning formatting
    
    Previously the modules were smashed together at the end of the line. As
    the header is quite long, this meant for quite long lines which wrapped
    on smaller terminals.
    
    err msg: A
             B
    
    Now they are nested underneath the long first line of the error message.
    
    err msg:
      A
      B
    
    Reviewers: bgamari
    
    Reviewed By: bgamari
    
    Subscribers: rwbarton, thomie, carter
    
    Differential Revision: https://phabricator.haskell.org/D4454


>---------------------------------------------------------------

6a7e159ce25b432824f8757e0c768f2b2e2754df
 compiler/main/GhcMake.hs | 13 +++++++++----
 1 file changed, 9 insertions(+), 4 deletions(-)

diff --git a/compiler/main/GhcMake.hs b/compiler/main/GhcMake.hs
index 73a7157..d399d03 100644
--- a/compiler/main/GhcMake.hs
+++ b/compiler/main/GhcMake.hs
@@ -201,11 +201,16 @@ warnMissingHomeModules hsc_env mod_graph =
 
     msg
       | gopt Opt_BuildingCabalPackage dflags
-      = text "These modules are needed for compilation but not listed in your .cabal file's other-modules: "
-        <> sep (map ppr missing)
+      = hang
+          (text "These modules are needed for compilation but not listed in your .cabal file's other-modules: ")
+          4
+          (sep (map ppr missing))
       | otherwise
-      = text "Modules are not listed in command line but needed for compilation: "
-        <> sep (map ppr missing)
+      =
+        hang
+          (text "Modules are not listed in command line but needed for compilation: ")
+          4
+          (sep (map ppr missing))
     warn = makeIntoWarning
       (Reason Opt_WarnMissingHomeModules)
       (mkPlainErrMsg dflags noSrcSpan msg)


From git at git.haskell.org  Fri Mar  2 21:54:06 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Fri,  2 Mar 2018 21:54:06 +0000 (UTC)
Subject: [commit: ghc] master: Add @since annotations for derived instances in
 base (5c28ee8)
Message-ID: <20180302215406.E9F713A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/5c28ee88dd66617b0fd5dbe0d90142ce983a547e/ghc

>---------------------------------------------------------------

commit 5c28ee88dd66617b0fd5dbe0d90142ce983a547e
Author: Chaitanya Koparkar <ckoparkar at gmail.com>
Date:   Fri Mar 2 16:12:56 2018 -0500

    Add @since annotations for derived instances in base
    
    Test Plan: ./validate
    
    Reviewers: hvr, goldfire, bgamari, RyanGlScott
    
    Reviewed By: RyanGlScott
    
    Subscribers: rwbarton, thomie, carter
    
    GHC Trac Issues: #11767
    
    Differential Revision: https://phabricator.haskell.org/D4452


>---------------------------------------------------------------

5c28ee88dd66617b0fd5dbe0d90142ce983a547e
 libraries/base/Control/Applicative.hs          |  20 ++-
 libraries/base/Control/Concurrent/Chan.hs      |   2 +-
 libraries/base/Data/Complex.hs                 |  12 +-
 libraries/base/Data/Data.hs                    |  14 +-
 libraries/base/Data/Either.hs                  |   7 +-
 libraries/base/Data/Fixed.hs                   |   6 +-
 libraries/base/Data/Foldable.hs                |  27 ++++
 libraries/base/Data/Functor/Compose.hs         |   5 +-
 libraries/base/Data/Functor/Const.hs           |  23 ++-
 libraries/base/Data/Functor/Identity.hs        |  23 ++-
 libraries/base/Data/Functor/Product.hs         |   5 +-
 libraries/base/Data/Functor/Sum.hs             |   5 +-
 libraries/base/Data/Monoid.hs                  |  24 ++-
 libraries/base/Data/Ord.hs                     |  10 +-
 libraries/base/Data/Proxy.hs                   |   4 +-
 libraries/base/Data/Semigroup.hs               |  70 +++++++--
 libraries/base/Data/Semigroup/Internal.hs      |  64 +++++++-
 libraries/base/Data/String.hs                  |   2 +
 libraries/base/Data/Traversable.hs             |  28 ++++
 libraries/base/Data/Type/Coercion.hs           |   5 +
 libraries/base/Data/Type/Equality.hs           |   5 +
 libraries/base/Data/Version.hs                 |   5 +-
 libraries/base/GHC/Base.hs                     |   8 +-
 libraries/base/GHC/ByteOrder.hs                |   8 +-
 libraries/base/GHC/Conc/Sync.hs                |  10 +-
 libraries/base/GHC/Conc/Windows.hs             |   7 +-
 libraries/base/GHC/Event/Control.hs            |   4 +-
 libraries/base/GHC/Event/EPoll.hsc             |   7 +-
 libraries/base/GHC/Event/Internal.hs           |  16 +-
 libraries/base/GHC/Event/KQueue.hsc            |  25 ++-
 libraries/base/GHC/Event/Manager.hs            |   8 +-
 libraries/base/GHC/Event/Poll.hsc              |  10 +-
 libraries/base/GHC/Event/TimerManager.hs       |   6 +-
 libraries/base/GHC/Event/Unique.hs             |   5 +-
 libraries/base/GHC/Exception.hs                |   8 +-
 libraries/base/GHC/Exts.hs                     |   4 +-
 libraries/base/GHC/Fingerprint/Type.hs         |   4 +-
 libraries/base/GHC/Generics.hs                 | 210 ++++++++++++++++++++++---
 libraries/base/GHC/IO.hs                       |   4 +-
 libraries/base/GHC/IO/Buffer.hs                |   3 +-
 libraries/base/GHC/IO/Device.hs                |  11 +-
 libraries/base/GHC/IO/Encoding/Failure.hs      |   3 +-
 libraries/base/GHC/IO/Encoding/Types.hs        |   4 +-
 libraries/base/GHC/IO/Exception.hs             |   8 +-
 libraries/base/GHC/IO/Handle/Lock.hsc          |   3 +-
 libraries/base/GHC/IO/Handle/Types.hs          |  18 ++-
 libraries/base/GHC/IO/IOMode.hs                |   8 +-
 libraries/base/GHC/IORef.hs                    |   2 +-
 libraries/base/GHC/Natural.hs                  |   6 +-
 libraries/base/GHC/Ptr.hs                      |   5 +-
 libraries/base/GHC/RTS/Flags.hsc               |  42 +++--
 libraries/base/GHC/Read.hs                     |   2 +
 libraries/base/GHC/Real.hs                     |   2 +-
 libraries/base/GHC/Show.hs                     |  15 ++
 libraries/base/GHC/Stable.hs                   |   2 +-
 libraries/base/GHC/Stack/Types.hs              |   2 +-
 libraries/base/GHC/StaticPtr.hs                |   2 +-
 libraries/base/GHC/Stats.hsc                   |   8 +-
 libraries/base/GHC/Unicode.hs                  |   9 +-
 libraries/base/System/Timeout.hs               |   4 +-
 libraries/base/Text/ParserCombinators/ReadP.hs |   2 +-
 libraries/base/Text/Read/Lex.hs                |  10 +-
 62 files changed, 734 insertions(+), 147 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc 5c28ee88dd66617b0fd5dbe0d90142ce983a547e

From git at git.haskell.org  Fri Mar  2 21:54:09 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Fri,  2 Mar 2018 21:54:09 +0000 (UTC)
Subject: [commit: ghc] master: rts/win32: Assert that the IO manager has been
 initialised (6e4fa81)
Message-ID: <20180302215409.B63BC3A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/6e4fa8175677c39441f1502c58a832e79570cb0d/ghc

>---------------------------------------------------------------

commit 6e4fa8175677c39441f1502c58a832e79570cb0d
Author: Simon Jakobi <simon.jakobi at gmail.com>
Date:   Fri Mar 2 16:13:26 2018 -0500

    rts/win32: Assert that the IO manager has been initialised
    
    Reviewers: bgamari, erikd, simonmar
    
    Reviewed By: bgamari
    
    Subscribers: rwbarton, thomie, carter
    
    Differential Revision: https://phabricator.haskell.org/D4450


>---------------------------------------------------------------

6e4fa8175677c39441f1502c58a832e79570cb0d
 rts/win32/IOManager.c | 33 +++++++++++++++------------------
 1 file changed, 15 insertions(+), 18 deletions(-)

diff --git a/rts/win32/IOManager.c b/rts/win32/IOManager.c
index 216e725..f155180 100644
--- a/rts/win32/IOManager.c
+++ b/rts/win32/IOManager.c
@@ -435,13 +435,12 @@ AddIORequest ( int   fd,
                char* buffer,
                CompletionProc onCompletion)
 {
+    ASSERT(ioMan);
+
     WorkItem* wItem    = (WorkItem*)malloc(sizeof(WorkItem));
-    unsigned int reqID;
-    if (!ioMan || !wItem) {
-        free(wItem);
-        return 0;
-    }
-    reqID = ioMan->requestID++;
+    if (!wItem) return 0;
+
+    unsigned int reqID = ioMan->requestID++;
 
     /* Fill in the blanks */
     wItem->workKind     = ( isSocket   ? WORKER_FOR_SOCKET : 0 ) |
@@ -467,13 +466,12 @@ BOOL
 AddDelayRequest ( HsInt          usecs,
                   CompletionProc onCompletion)
 {
+    ASSERT(ioMan);
+
     WorkItem* wItem = (WorkItem*)malloc(sizeof(WorkItem));
-    unsigned int reqID;
-    if (!ioMan || !wItem) {
-        free(wItem);
-        return false;
-    }
-    reqID = ioMan->requestID++;
+    if (!wItem) return false;
+
+    unsigned int reqID = ioMan->requestID++;
 
     /* Fill in the blanks */
     wItem->workKind     = WORKER_DELAY;
@@ -495,13 +493,12 @@ AddProcRequest ( void* proc,
                  void* param,
                  CompletionProc onCompletion)
 {
+    ASSERT(ioMan);
+
     WorkItem* wItem = (WorkItem*)malloc(sizeof(WorkItem));
-    unsigned int reqID;
-    if (!ioMan || !wItem) {
-        free(wItem);
-        return false;
-    }
-    reqID = ioMan->requestID++;
+    if (!wItem) return false;
+
+    unsigned int reqID = ioMan->requestID++;
 
     /* Fill in the blanks */
     wItem->workKind     = WORKER_DO_PROC;


From git at git.haskell.org  Fri Mar  2 21:54:12 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Fri,  2 Mar 2018 21:54:12 +0000 (UTC)
Subject: [commit: ghc] master: configure: Enable LD_NO_GOLD is set in all
 codepaths (bc1bcaa)
Message-ID: <20180302215412.81AC43A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/bc1bcaa2c0c66fb247d1338d6d0055a833918a7f/ghc

>---------------------------------------------------------------

commit bc1bcaa2c0c66fb247d1338d6d0055a833918a7f
Author: Ben Gamari <bgamari.foss at gmail.com>
Date:   Fri Mar 2 16:13:53 2018 -0500

    configure: Enable LD_NO_GOLD is set in all codepaths
    
    Test Plan: `./configure --disable-ld-override; make; make install`
    
    Reviewers: trofi, hvr
    
    Reviewed By: trofi
    
    Subscribers: rwbarton, thomie, erikd, carter, simonmar
    
    GHC Trac Issues: #14675
    
    Differential Revision: https://phabricator.haskell.org/D4448


>---------------------------------------------------------------

bc1bcaa2c0c66fb247d1338d6d0055a833918a7f
 aclocal.m4 | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/aclocal.m4 b/aclocal.m4
index 5ad3752..a2fdbdc 100644
--- a/aclocal.m4
+++ b/aclocal.m4
@@ -2379,12 +2379,16 @@ AC_DEFUN([FIND_LD],[
 
         # Fallback
         AC_CHECK_TARGET_TOOL([LD], [ld])
+        # This isn't entirely safe since $LD may have been discovered to be
+        $ ld.gold, but what else can we do?
+        if test "x$LD_NO_GOLD" = "x"; then LD_NO_GOLD=$LD; fi
     }
 
     if test "x$enable_ld_override" = "xyes"; then
         find_ld
     else
         AC_CHECK_TARGET_TOOL([LD], [ld])
+        if test "x$LD_NO_GOLD" = "x"; then LD_NO_GOLD=$LD; fi
     fi
 
     CHECK_LD_COPY_BUG([$1])


From git at git.haskell.org  Fri Mar  2 21:54:15 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Fri,  2 Mar 2018 21:54:15 +0000 (UTC)
Subject: [commit: ghc] master: Add Applicative, Semigroup,
 and Monoid instances in GHC.Generics (7782b47)
Message-ID: <20180302215415.4CF523A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/7782b47c4193975123edd3af630e6fe59ac7ef73/ghc

>---------------------------------------------------------------

commit 7782b47c4193975123edd3af630e6fe59ac7ef73
Author: Lysxia <lysxia at gmail.com>
Date:   Fri Mar 2 16:14:36 2018 -0500

    Add Applicative, Semigroup, and Monoid instances in GHC.Generics
    
    Reviewers: hvr, bgamari, alpmestan, RyanGlScott
    
    Reviewed By: RyanGlScott
    
    Subscribers: RyanGlScott, rwbarton, thomie, carter
    
    Differential Revision: https://phabricator.haskell.org/D4447


>---------------------------------------------------------------

7782b47c4193975123edd3af630e6fe59ac7ef73
 libraries/base/GHC/Generics.hs | 59 +++++++++++++++++++++++++++++++++++++++++-
 libraries/base/changelog.md    |  3 +++
 2 files changed, 61 insertions(+), 1 deletion(-)

diff --git a/libraries/base/GHC/Generics.hs b/libraries/base/GHC/Generics.hs
index ff44cf8..9ac0528 100644
--- a/libraries/base/GHC/Generics.hs
+++ b/libraries/base/GHC/Generics.hs
@@ -740,7 +740,8 @@ import GHC.Types
 -- Needed for instances
 import GHC.Arr     ( Ix )
 import GHC.Base    ( Alternative(..), Applicative(..), Functor(..)
-                   , Monad(..), MonadPlus(..), NonEmpty(..), String, coerce )
+                   , Monad(..), MonadPlus(..), NonEmpty(..), String, coerce
+                   , Semigroup(..), Monoid(..) )
 import GHC.Classes ( Eq(..), Ord(..) )
 import GHC.Enum    ( Bounded, Enum )
 import GHC.Read    ( Read(..) )
@@ -765,6 +766,10 @@ data V1 (p :: k)
            , Generic1 -- ^ @since 4.9.0.0
            )
 
+-- | @since 4.12.0.0
+instance Semigroup (V1 p) where
+  v <> _ = v
+
 -- | Unit: used for constructors without arguments
 data U1 (p :: k) = U1
   deriving ( Generic  -- ^ @since 4.7.0.0
@@ -808,6 +813,14 @@ instance Monad U1 where
 -- | @since 4.9.0.0
 instance MonadPlus U1
 
+-- | @since 4.12.0.0
+instance Semigroup (U1 p) where
+  _ <> _ = U1
+
+-- | @since 4.12.0.0
+instance Monoid (U1 p) where
+  mempty = U1
+
 -- | Used for marking occurrences of the parameter
 newtype Par1 p = Par1 { unPar1 :: p }
   deriving ( Eq       -- ^ @since 4.7.0.0
@@ -829,6 +842,12 @@ instance Applicative Par1 where
 instance Monad Par1 where
   Par1 x >>= f = f x
 
+-- | @since 4.12.0.0
+deriving instance Semigroup p => Semigroup (Par1 p)
+
+-- | @since 4.12.0.0
+deriving instance Monoid p => Monoid (Par1 p)
+
 -- | Recursive calls of kind @* -> *@ (or kind @k -> *@, when @PolyKinds@
 -- is enabled)
 newtype Rec1 (f :: k -> *) (p :: k) = Rec1 { unRec1 :: f p }
@@ -854,6 +873,12 @@ instance Monad f => Monad (Rec1 f) where
 -- | @since 4.9.0.0
 deriving instance MonadPlus f => MonadPlus (Rec1 f)
 
+-- | @since 4.12.0.0
+deriving instance Semigroup (f p) => Semigroup (Rec1 f p)
+
+-- | @since 4.12.0.0
+deriving instance Monoid (f p) => Monoid (Rec1 f p)
+
 -- | Constants, additional parameters and recursion of kind @*@
 newtype K1 (i :: *) c (p :: k) = K1 { unK1 :: c }
   deriving ( Eq       -- ^ @since 4.7.0.0
@@ -865,6 +890,18 @@ newtype K1 (i :: *) c (p :: k) = K1 { unK1 :: c }
            , Generic1 -- ^ @since 4.9.0.0
            )
 
+-- | @since 4.12.0.0
+instance Monoid c => Applicative (K1 i c) where
+  pure _ = K1 mempty
+  liftA2 = \_ -> coerce (mappend :: c -> c -> c)
+  (<*>) = coerce (mappend :: c -> c -> c)
+
+-- | @since 4.12.0.0
+deriving instance Semigroup c => Semigroup (K1 i c p)
+
+-- | @since 4.12.0.0
+deriving instance Monoid c => Monoid (K1 i c p)
+
 -- | @since 4.9.0.0
 deriving instance Applicative f => Applicative (M1 i c f)
 
@@ -877,6 +914,12 @@ deriving instance Monad f => Monad (M1 i c f)
 -- | @since 4.9.0.0
 deriving instance MonadPlus f => MonadPlus (M1 i c f)
 
+-- | @since 4.12.0.0
+deriving instance Semigroup (f p) => Semigroup (M1 i c f p)
+
+-- | @since 4.12.0.0
+deriving instance Monoid (f p) => Monoid (M1 i c f p)
+
 -- | Meta-information (constructor names, etc.)
 newtype M1 (i :: *) (c :: Meta) (f :: k -> *) (p :: k) = M1 { unM1 :: f p }
   deriving ( Eq       -- ^ @since 4.7.0.0
@@ -933,6 +976,14 @@ instance (Monad f, Monad g) => Monad (f :*: g) where
 -- | @since 4.9.0.0
 instance (MonadPlus f, MonadPlus g) => MonadPlus (f :*: g)
 
+-- | @since 4.12.0.0
+instance (Semigroup (f p), Semigroup (g p)) => Semigroup ((f :*: g) p) where
+  (x1 :*: y1) <> (x2 :*: y2) = (x1 <> x2) :*: (y1 <> y2)
+
+-- | @since 4.12.0.0
+instance (Monoid (f p), Monoid (g p)) => Monoid ((f :*: g) p) where
+  mempty = mempty :*: mempty
+
 -- | Composition of functors
 infixr 7 :.:
 newtype (:.:) (f :: k2 -> *) (g :: k1 -> k2) (p :: k1) =
@@ -958,6 +1009,12 @@ instance (Alternative f, Applicative g) => Alternative (f :.: g) where
   (<|>) = coerce ((<|>) :: f (g a) -> f (g a) -> f (g a)) ::
     forall a . (f :.: g) a -> (f :.: g) a -> (f :.: g) a
 
+-- | @since 4.12.0.0
+deriving instance Semigroup (f (g p)) => Semigroup ((f :.: g) p)
+
+-- | @since 4.12.0.0
+deriving instance Monoid (f (g p)) => Monoid ((f :.: g) p)
+
 -- | Constants of unlifted kinds
 --
 -- @since 4.9.0.0
diff --git a/libraries/base/changelog.md b/libraries/base/changelog.md
index fdac6f2..47fe011 100644
--- a/libraries/base/changelog.md
+++ b/libraries/base/changelog.md
@@ -6,6 +6,9 @@
 
   * `($!)` is now representation-polymorphic like `($)`.
 
+  * Add `Applicative` (for `K1`), `Semigroup` and `Monoid` instances in
+    `GHC.Generics`. (#14849)
+
 ## 4.11.0.0 *TBA*
   * Bundled with GHC 8.4.1
 


From git at git.haskell.org  Fri Mar  2 21:54:18 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Fri,  2 Mar 2018 21:54:18 +0000 (UTC)
Subject: [commit: ghc] master: Adds *-cross-ncg flavour. (e4dcebf)
Message-ID: <20180302215418.B023E3A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/e4dcebf899c796a13dabf8964038f78505b9f4ec/ghc

>---------------------------------------------------------------

commit e4dcebf899c796a13dabf8964038f78505b9f4ec
Author: Moritz Angermann <moritz.angermann at gmail.com>
Date:   Fri Mar 2 16:15:09 2018 -0500

    Adds *-cross-ncg flavour.
    
    Our *-cross flavours force -fllvm, this adds flavours for cross
    compilation to x86_64, where we can use our native code generator.
    
    Test Plan: ./validate
    
    Reviewers: bgamari
    
    Reviewed By: bgamari
    
    Subscribers: rwbarton, thomie, carter
    
    Differential Revision: https://phabricator.haskell.org/D4443


>---------------------------------------------------------------

e4dcebf899c796a13dabf8964038f78505b9f4ec
 mk/build.mk.sample                                 | 17 +++++++++++++----
 mk/flavours/{bench-cross.mk => bench-cross-ncg.mk} |  4 ++--
 mk/flavours/{perf-cross.mk => perf-cross-ncg.mk}   |  4 ++--
 mk/flavours/{quick-cross.mk => quick-cross-ncg.mk} |  4 ++--
 4 files changed, 19 insertions(+), 10 deletions(-)

diff --git a/mk/build.mk.sample b/mk/build.mk.sample
index 958cea7..ce7b4d6 100644
--- a/mk/build.mk.sample
+++ b/mk/build.mk.sample
@@ -13,17 +13,23 @@
 # As above but build GHC using the LLVM backend
 #BuildFlavour = perf-llvm
 
-# Perf build configured for a cross-compiler
+# Perf build configured for a cross-compiler (using the LLVM backend)
 #BuildFlavour = perf-cross
 
+# Perf build configured for a cross-compiler (using the NCG backend)
+#BuildFlavour = perf-cross-ncg
+
 # Fast build with optimised libraries, no profiling (RECOMMENDED):
 #BuildFlavour = quick
 
 # Fast build with optimised libraries, no profiling, with LLVM:
 #BuildFlavour = quick-llvm
 
-# Fast build configured for a cross compiler
-#BuildFlavour  = quick-cross
+# Fast build configured for a cross compiler (using the LLVM backend)
+#BuildFlavour = quick-cross
+
+# Fast build configured for a cross compiler (using the NCG backend)
+#BuildFlavour = quick-cross-ncg
 
 # Even faster build.  NOT RECOMMENDED: the libraries will be
 # completely unoptimised, so any code built with this compiler
@@ -51,9 +57,12 @@
 # As above but build GHC using the LLVM backend
 #BuildFlavour = bench-llvm
 
-# Bench build configured for a cross-compiler
+# Bench build configured for a cross-compiler (using the LLVM backend)
 #BuildFlavour = bench-cross
 
+# Bench build configured for a cross-compiler (using the NCG backend)
+#BuildFlavour = bench-cross-ncg
+
 # Use the same settings as validate.
 #BuildFlavour = validate
 
diff --git a/mk/flavours/bench-cross.mk b/mk/flavours/bench-cross-ncg.mk
similarity index 85%
copy from mk/flavours/bench-cross.mk
copy to mk/flavours/bench-cross-ncg.mk
index ae67f34..6b686af 100644
--- a/mk/flavours/bench-cross.mk
+++ b/mk/flavours/bench-cross-ncg.mk
@@ -1,7 +1,7 @@
 SRC_HC_OPTS        = -O -H64m
 GhcStage1HcOpts    = -O
-GhcStage2HcOpts    = -O0 -fllvm
-GhcLibHcOpts       = -O2 -fllvm
+GhcStage2HcOpts    = -O0
+GhcLibHcOpts       = -O2
 BUILD_PROF_LIBS    = NO
 SplitObjs          = NO
 SplitSections      = NO
diff --git a/mk/flavours/perf-cross.mk b/mk/flavours/perf-cross-ncg.mk
similarity index 83%
copy from mk/flavours/perf-cross.mk
copy to mk/flavours/perf-cross-ncg.mk
index f202642..4b94c48 100644
--- a/mk/flavours/perf-cross.mk
+++ b/mk/flavours/perf-cross-ncg.mk
@@ -1,7 +1,7 @@
 SRC_HC_OPTS        = -O -H64m
 GhcStage1HcOpts    = -O2
-GhcStage2HcOpts    = -O2 -fllvm
-GhcLibHcOpts       = -O2 -fllvm
+GhcStage2HcOpts    = -O2
+GhcLibHcOpts       = -O2
 BUILD_PROF_LIBS    = YES
 #SplitObjs
 HADDOCK_DOCS       = NO
diff --git a/mk/flavours/quick-cross.mk b/mk/flavours/quick-cross-ncg.mk
similarity index 85%
copy from mk/flavours/quick-cross.mk
copy to mk/flavours/quick-cross-ncg.mk
index f0f00d2..97352cc 100644
--- a/mk/flavours/quick-cross.mk
+++ b/mk/flavours/quick-cross-ncg.mk
@@ -1,7 +1,7 @@
 SRC_HC_OPTS        = -O0 -H64m
 GhcStage1HcOpts    = -O
-GhcStage2HcOpts    = -O0 -fllvm
-GhcLibHcOpts       = -O -fllvm
+GhcStage2HcOpts    = -O0
+GhcLibHcOpts       = -O
 BUILD_PROF_LIBS    = NO
 SplitObjs          = NO
 SplitSections      = NO


From git at git.haskell.org  Fri Mar  2 21:54:22 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Fri,  2 Mar 2018 21:54:22 +0000 (UTC)
Subject: [commit: ghc] master: Permit conversion of partially applied
 PromotedTupleTs (6835702)
Message-ID: <20180302215422.1F6E53A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/68357020b1cf29d4306e769b3366feb9a65ae78c/ghc

>---------------------------------------------------------------

commit 68357020b1cf29d4306e769b3366feb9a65ae78c
Author: Ryan Scott <ryan.gl.scott at gmail.com>
Date:   Fri Mar 2 16:15:38 2018 -0500

    Permit conversion of partially applied PromotedTupleTs
    
    Summary:
    We were simply missing a case in `Convert` for when have a
    `PromotedTupleT` that wasn't fully saturated. Easily fixed.
    
    Test Plan: make test TEST=T14843
    
    Reviewers: goldfire, bgamari
    
    Reviewed By: bgamari
    
    Subscribers: rwbarton, thomie, carter
    
    GHC Trac Issues: #14843
    
    Differential Revision: https://phabricator.haskell.org/D4442


>---------------------------------------------------------------

68357020b1cf29d4306e769b3366feb9a65ae78c
 compiler/hsSyn/Convert.hs    | 3 +++
 testsuite/tests/th/T14843.hs | 9 +++++++++
 testsuite/tests/th/all.T     | 1 +
 3 files changed, 13 insertions(+)

diff --git a/compiler/hsSyn/Convert.hs b/compiler/hsSyn/Convert.hs
index e137b1e..c1cf77b 100644
--- a/compiler/hsSyn/Convert.hs
+++ b/compiler/hsSyn/Convert.hs
@@ -1301,6 +1301,9 @@ cvtTypeKind ty_str ty
              -> do  { let kis = replicate m placeHolderKind
                     ; returnL (HsExplicitTupleTy kis tys')
                     }
+             | otherwise
+             -> mk_apps (HsTyVar NotPromoted
+                               (noLoc (getRdrName (tupleDataCon Boxed n)))) tys'
              where
                m = length tys'
 
diff --git a/testsuite/tests/th/T14843.hs b/testsuite/tests/th/T14843.hs
new file mode 100644
index 0000000..505fa51
--- /dev/null
+++ b/testsuite/tests/th/T14843.hs
@@ -0,0 +1,9 @@
+{-# LANGUAGE DataKinds #-}
+{-# LANGUAGE TemplateHaskell #-}
+module T14843 where
+
+import Language.Haskell.TH.Syntax
+
+type T1 = $(return (PromotedTupleT 2))
+type T2 = $([t| '(,) |])
+type T3 = $(return (PromotedT (tupleDataName 2)))
diff --git a/testsuite/tests/th/all.T b/testsuite/tests/th/all.T
index 7305800..50e7314 100644
--- a/testsuite/tests/th/all.T
+++ b/testsuite/tests/th/all.T
@@ -400,3 +400,4 @@ test('T14060', normal, compile_and_run, ['-v0'])
 test('T14646', normal, compile, ['-v0 -ddump-splices -dsuppress-uniques'])
 test('T14681', normal, compile, ['-v0 -ddump-splices -dsuppress-uniques'])
 test('T14817', normal, compile, ['-v0 -ddump-splices -dsuppress-uniques'])
+test('T14843', normal, compile, ['-v0'])


From git at git.haskell.org  Fri Mar  2 21:54:26 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Fri,  2 Mar 2018 21:54:26 +0000 (UTC)
Subject: [commit: ghc] master: Fix #14838 by marking TH-spliced code as
 FromSource (ffb2738)
Message-ID: <20180302215426.1E0903A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/ffb2738f86c4e4c3f0eaacf0a95d7326fdd2e383/ghc

>---------------------------------------------------------------

commit ffb2738f86c4e4c3f0eaacf0a95d7326fdd2e383
Author: Ryan Scott <ryan.gl.scott at gmail.com>
Date:   Fri Mar 2 16:16:17 2018 -0500

    Fix #14838 by marking TH-spliced code as FromSource
    
    Previously, any Template Haskell code that was spliced would
    be marked as `Generated`, which would completely suppress pattern-
    match coverage warnings for it, which several folks found confusing.
    Indeed, Template Haskell-spliced code is "source" code in some sense,
    as users specifically request that it be put into their program, so
    changing its designation to `FromSource` makes sense from that
    perspective.
    
    Test Plan: make test TEST=T14838
    
    Reviewers: goldfire, bgamari
    
    Reviewed By: bgamari
    
    Subscribers: rwbarton, thomie, carter
    
    GHC Trac Issues: #14838
    
    Differential Revision: https://phabricator.haskell.org/D4440


>---------------------------------------------------------------

ffb2738f86c4e4c3f0eaacf0a95d7326fdd2e383
 compiler/hsSyn/Convert.hs        |  4 ++--
 compiler/hsSyn/HsUtils.hs        | 14 +++++++-------
 compiler/parser/RdrHsSyn.hs      | 10 +++++-----
 compiler/typecheck/TcGenDeriv.hs |  8 +++++---
 testsuite/tests/th/T14838.hs     | 14 ++++++++++++++
 testsuite/tests/th/T14838.stderr | 18 ++++++++++++++++++
 testsuite/tests/th/T14838Lib.hs  | 14 ++++++++++++++
 testsuite/tests/th/all.T         |  2 ++
 8 files changed, 67 insertions(+), 17 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc ffb2738f86c4e4c3f0eaacf0a95d7326fdd2e383

From git at git.haskell.org  Fri Mar  2 21:54:28 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Fri,  2 Mar 2018 21:54:28 +0000 (UTC)
Subject: [commit: ghc] master: doCorePass: Expand catch-all (44ba60f)
Message-ID: <20180302215428.EB23B3A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/44ba60fe9bce298cfa41c4505d029c1a2c6e5671/ghc

>---------------------------------------------------------------

commit 44ba60fe9bce298cfa41c4505d029c1a2c6e5671
Author: Simon Jakobi <simon.jakobi at gmail.com>
Date:   Fri Mar 2 16:17:12 2018 -0500

    doCorePass: Expand catch-all
    
    This doesn't remedy problem, but at least it's more explicit than
    the catch-all
    
    Reviewers: bgamari
    
    Reviewed By: bgamari
    
    Subscribers: rwbarton, thomie, carter
    
    GHC Trac Issues: #14544
    
    Differential Revision: https://phabricator.haskell.org/D4435


>---------------------------------------------------------------

44ba60fe9bce298cfa41c4505d029c1a2c6e5671
 compiler/simplCore/SimplCore.hs | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/compiler/simplCore/SimplCore.hs b/compiler/simplCore/SimplCore.hs
index 4dfa198..0a20eb0 100644
--- a/compiler/simplCore/SimplCore.hs
+++ b/compiler/simplCore/SimplCore.hs
@@ -486,9 +486,15 @@ doCorePass (CoreDoPasses passes)        = runCorePasses passes
 
 #if defined(GHCI)
 doCorePass (CoreDoPluginPass _ pass) = {-# SCC "Plugin" #-} pass
+#else
+doCorePass pass at CoreDoPluginPass {}  = pprPanic "doCorePass" (ppr pass)
 #endif
 
-doCorePass pass = pprPanic "doCorePass" (ppr pass)
+doCorePass pass at CoreDesugar          = pprPanic "doCorePass" (ppr pass)
+doCorePass pass at CoreDesugarOpt       = pprPanic "doCorePass" (ppr pass)
+doCorePass pass at CoreTidy             = pprPanic "doCorePass" (ppr pass)
+doCorePass pass at CorePrep             = pprPanic "doCorePass" (ppr pass)
+doCorePass pass at CoreOccurAnal        = pprPanic "doCorePass" (ppr pass)
 
 {-
 ************************************************************************


From git at git.haskell.org  Fri Mar  2 21:54:31 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Fri,  2 Mar 2018 21:54:31 +0000 (UTC)
Subject: [commit: ghc] master: Compile with `--via-asm` when cross compiling.
 (5f6fcf7)
Message-ID: <20180302215431.C0C5D3A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/5f6fcf7808b16d066ad0fb2068225b3f2e8363f7/ghc

>---------------------------------------------------------------

commit 5f6fcf7808b16d066ad0fb2068225b3f2e8363f7
Author: Moritz Angermann <moritz.angermann at gmail.com>
Date:   Fri Mar 2 16:16:52 2018 -0500

    Compile with `--via-asm` when cross compiling.
    
    This bumps `hsc2hs` and adds the new `--via-asm` flag,
    which allows to successfully cross compile the win32
    lirbary.
    
    - Compile with `--via-asm` when cross compiling. This requires
    haskell/hsc2hs#5 (https://github.com/haskell/hsc2hs/pull/5)
    
    Test Plan: ./validate
    
    Reviewers: bgamari
    
    Reviewed By: bgamari
    
    Subscribers: rwbarton, thomie, carter
    
    Differential Revision: https://phabricator.haskell.org/D4439


>---------------------------------------------------------------

5f6fcf7808b16d066ad0fb2068225b3f2e8363f7
 mk/config.mk.in | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/mk/config.mk.in b/mk/config.mk.in
index e5ec04a..26b07f3 100644
--- a/mk/config.mk.in
+++ b/mk/config.mk.in
@@ -649,8 +649,12 @@ $(eval $(call set_stage_HSC2HS_OPTS,0))
 $(eval $(call set_stage_HSC2HS_OPTS,1))
 $(eval $(call set_stage_HSC2HS_OPTS,2))
 ifeq "$(CrossCompiling)" "YES"
-SRC_HSC2HS_OPTS_STAGE1 += --cross-compile
-SRC_HSC2HS_OPTS_STAGE2 += --cross-compile
+# We'll assume we compile with gcc or clang, and both support `-S` and can as such use the
+# --via-asm pass, which should be faster and is required for cross compiling to windows, as
+# the c compiler complains about non-constant expressions even though they are constant and
+# end up as constants in the assembly.
+SRC_HSC2HS_OPTS_STAGE1 += --cross-compile --via-asm
+SRC_HSC2HS_OPTS_STAGE2 += --cross-compile --via-asm
 endif
 SRC_HSC2HS_OPTS_STAGE0 += --cflag=-D$(HostArch_CPP)_HOST_ARCH --cflag=-D$(HostOS_CPP)_HOST_OS
 SRC_HSC2HS_OPTS_STAGE1 += --cflag=-D$(TargetArch_CPP)_HOST_ARCH --cflag=-D$(TargetOS_CPP)_HOST_OS


From git at git.haskell.org  Fri Mar  2 21:54:35 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Fri,  2 Mar 2018 21:54:35 +0000 (UTC)
Subject: [commit: ghc] master: Fix the coverage checker's treatment of
 existential tyvars (a2d03c6)
Message-ID: <20180302215435.782363A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/a2d03c69b782212e6c476cfc1870bae493a4ac89/ghc

>---------------------------------------------------------------

commit a2d03c69b782212e6c476cfc1870bae493a4ac89
Author: Ryan Scott <ryan.gl.scott at gmail.com>
Date:   Fri Mar 2 16:18:04 2018 -0500

    Fix the coverage checker's treatment of existential tyvars
    
    Previously, the pattern-match coverage checker was far too
    eager to freshen the names of existentially quantified type
    variables, which led to incorrect sets of type constraints that
    misled GHC into thinking that certain programs that involve nested
    GADT pattern matches were non-exhaustive (when in fact they were).
    Now, we generate extra equality constraints in the ConCon case of
    the coverage algorithm to ensure that these fresh tyvars align
    with existing existential tyvars. See
    `Note [Coverage checking and existential tyvars]` for the full story.
    
    Test Plan: make test TEST="T11984 T14098"
    
    Reviewers: gkaracha, bgamari, simonpj
    
    Reviewed By: simonpj
    
    Subscribers: simonpj, rwbarton, thomie, carter
    
    GHC Trac Issues: #11984, #14098
    
    Differential Revision: https://phabricator.haskell.org/D4434


>---------------------------------------------------------------

a2d03c69b782212e6c476cfc1870bae493a4ac89
 compiler/deSugar/Check.hs                        | 143 ++++++++++++++++++++++-
 testsuite/tests/pmcheck/should_compile/T11984.hs |  23 ++++
 testsuite/tests/pmcheck/should_compile/T14098.hs |  24 ++++
 testsuite/tests/pmcheck/should_compile/all.T     |   4 +
 4 files changed, 188 insertions(+), 6 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc a2d03c69b782212e6c476cfc1870bae493a4ac89

From git at git.haskell.org  Fri Mar  2 21:54:38 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Fri,  2 Mar 2018 21:54:38 +0000 (UTC)
Subject: [commit: ghc] master: Correct default -A value in RTS flag usage info
 (821daad)
Message-ID: <20180302215438.4EC223A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/821daadf65a3e146f8adf2802b3cb8b520d8d10e/ghc

>---------------------------------------------------------------

commit 821daadf65a3e146f8adf2802b3cb8b520d8d10e
Author: Simon Jakobi <simon.jakobi at gmail.com>
Date:   Fri Mar 2 16:17:44 2018 -0500

    Correct default -A value in RTS flag usage info
    
    Reviewers: bgamari, erikd, simonmar
    
    Reviewed By: bgamari
    
    Subscribers: rwbarton, thomie, carter
    
    Differential Revision: https://phabricator.haskell.org/D4441


>---------------------------------------------------------------

821daadf65a3e146f8adf2802b3cb8b520d8d10e
 rts/RtsFlags.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/rts/RtsFlags.c b/rts/RtsFlags.c
index 26171cf..eb33c9e 100644
--- a/rts/RtsFlags.c
+++ b/rts/RtsFlags.c
@@ -277,7 +277,7 @@ usage_text[] = {
 "  -kc<size> Sets the stack chunk size (default 32k)",
 "  -kb<size> Sets the stack chunk buffer size (default 1k)",
 "",
-"  -A<size>  Sets the minimum allocation area size (default 512k) Egs: -A1m -A10k",
+"  -A<size>  Sets the minimum allocation area size (default 1m) Egs: -A20m -A10k",
 "  -AL<size> Sets the amount of large-object memory that can be allocated",
 "            before a GC is triggered (default: the value of -A)",
 "  -n<size>  Allocation area chunk size (0 = disabled, default: 0)",


From git at git.haskell.org  Fri Mar  2 22:34:49 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Fri,  2 Mar 2018 22:34:49 +0000 (UTC)
Subject: [commit: ghc] ghc-8.4: Fix missing code example in changelog for
 8.4.1 (353ed7d)
Message-ID: <20180302223449.534FB3A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : ghc-8.4
Link       : http://ghc.haskell.org/trac/ghc/changeset/353ed7d7dfe08c8e9c1a4c899d10cbe258a5c031/ghc

>---------------------------------------------------------------

commit 353ed7d7dfe08c8e9c1a4c899d10cbe258a5c031
Author: Sergey Vinokurov <serg.foo at gmail.com>
Date:   Wed Feb 7 21:10:17 2018 +0000

    Fix missing code example in changelog for 8.4.1
    
    (cherry picked from commit 3ae408cf93d10b9a2e5acb4186dc8e0c62e0afb6)


>---------------------------------------------------------------

353ed7d7dfe08c8e9c1a4c899d10cbe258a5c031
 docs/users_guide/8.4.1-notes.rst | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/docs/users_guide/8.4.1-notes.rst b/docs/users_guide/8.4.1-notes.rst
index efd3b98..489f4c8 100644
--- a/docs/users_guide/8.4.1-notes.rst
+++ b/docs/users_guide/8.4.1-notes.rst
@@ -186,7 +186,7 @@ Compiler
     ``error``: ::
 
       instance Show (Empty a) where
-        showsPrec = "Void showsPrec"
+        showsPrec = error "Void showsPrec"
 
     Now, they emit code that inspects the argument. That is, if the argument
     diverges, then showing it will also diverge: ::


From git at git.haskell.org  Fri Mar  2 22:34:52 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Fri,  2 Mar 2018 22:34:52 +0000 (UTC)
Subject: [commit: ghc] ghc-8.4: Fix typo (739bb3e)
Message-ID: <20180302223452.1FB313A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : ghc-8.4
Link       : http://ghc.haskell.org/trac/ghc/changeset/739bb3ef0a3657eda637aa99a81ba11a2412a03e/ghc

>---------------------------------------------------------------

commit 739bb3ef0a3657eda637aa99a81ba11a2412a03e
Author: Sergey Vinokurov <serg.foo at gmail.com>
Date:   Thu Feb 8 09:17:53 2018 +0000

    Fix typo
    
    (cherry picked from commit 37e78029845a04d0ab4cc05e1790c648facdcb1f)


>---------------------------------------------------------------

739bb3ef0a3657eda637aa99a81ba11a2412a03e
 libraries/base/GHC/MVar.hs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libraries/base/GHC/MVar.hs b/libraries/base/GHC/MVar.hs
index d367f2b..818f6db 100644
--- a/libraries/base/GHC/MVar.hs
+++ b/libraries/base/GHC/MVar.hs
@@ -90,7 +90,7 @@ takeMVar :: MVar a -> IO a
 takeMVar (MVar mvar#) = IO $ \ s# -> takeMVar# mvar# s#
 
 -- |Atomically read the contents of an 'MVar'.  If the 'MVar' is
--- currently empty, 'readMVar' will wait until its full.
+-- currently empty, 'readMVar' will wait until it is full.
 -- 'readMVar' is guaranteed to receive the next 'putMVar'.
 --
 -- 'readMVar' is multiple-wakeup, so when multiple readers are


From git at git.haskell.org  Fri Mar  2 22:34:54 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Fri,  2 Mar 2018 22:34:54 +0000 (UTC)
Subject: [commit: ghc] ghc-8.4: List 'setEnv' as opposite of 'getEnv' (1cd5d6c)
Message-ID: <20180302223454.E39CA3A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : ghc-8.4
Link       : http://ghc.haskell.org/trac/ghc/changeset/1cd5d6cdf80280b634399849c46df8bef377c25d/ghc

>---------------------------------------------------------------

commit 1cd5d6cdf80280b634399849c46df8bef377c25d
Author: Sergey Vinokurov <serg.foo at gmail.com>
Date:   Wed Feb 7 21:49:56 2018 +0000

    List 'setEnv' as opposite of 'getEnv'
    
    It seems best to direct users to use 'System.Environment.setEnv'
    rather than 'System.Posix.Env.putEnv'. This is due to 'setEnv' being
    located in the same module as 'getEnv' and my virtue of working on
    Windows platform, whereas 'putEnv' does not have that quality because
    it's part of the 'unix' package.
    
    (cherry picked from commit c74fcf5d27744c67b09b29a78029c31c9371cf41)


>---------------------------------------------------------------

1cd5d6cdf80280b634399849c46df8bef377c25d
 libraries/base/System/Environment.hs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/libraries/base/System/Environment.hs b/libraries/base/System/Environment.hs
index 343b772..5604ca2 100644
--- a/libraries/base/System/Environment.hs
+++ b/libraries/base/System/Environment.hs
@@ -123,8 +123,8 @@ basename f = go f f
 
 
 -- | Computation 'getEnv' @var@ returns the value
--- of the environment variable @var at . For the inverse, POSIX users
--- can use 'System.Posix.Env.putEnv'.
+-- of the environment variable @var at . For the inverse, the
+-- `System.Environment.setEnv` function can be used.
 --
 -- This computation may fail with:
 --


From git at git.haskell.org  Fri Mar  2 22:34:57 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Fri,  2 Mar 2018 22:34:57 +0000 (UTC)
Subject: [commit: ghc] ghc-8.4: Correct default -A value in RTS flag usage
 info (11ac7ae)
Message-ID: <20180302223457.C45B13A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : ghc-8.4
Link       : http://ghc.haskell.org/trac/ghc/changeset/11ac7aec4960b66d8cf18eaf731b84a2b955d4cf/ghc

>---------------------------------------------------------------

commit 11ac7aec4960b66d8cf18eaf731b84a2b955d4cf
Author: Simon Jakobi <simon.jakobi at gmail.com>
Date:   Fri Mar 2 16:17:44 2018 -0500

    Correct default -A value in RTS flag usage info
    
    Reviewers: bgamari, erikd, simonmar
    
    Reviewed By: bgamari
    
    Subscribers: rwbarton, thomie, carter
    
    Differential Revision: https://phabricator.haskell.org/D4441
    
    (cherry picked from commit 821daadf65a3e146f8adf2802b3cb8b520d8d10e)


>---------------------------------------------------------------

11ac7aec4960b66d8cf18eaf731b84a2b955d4cf
 rts/RtsFlags.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/rts/RtsFlags.c b/rts/RtsFlags.c
index 26171cf..eb33c9e 100644
--- a/rts/RtsFlags.c
+++ b/rts/RtsFlags.c
@@ -277,7 +277,7 @@ usage_text[] = {
 "  -kc<size> Sets the stack chunk size (default 32k)",
 "  -kb<size> Sets the stack chunk buffer size (default 1k)",
 "",
-"  -A<size>  Sets the minimum allocation area size (default 512k) Egs: -A1m -A10k",
+"  -A<size>  Sets the minimum allocation area size (default 1m) Egs: -A20m -A10k",
 "  -AL<size> Sets the amount of large-object memory that can be allocated",
 "            before a GC is triggered (default: the value of -A)",
 "  -n<size>  Allocation area chunk size (0 = disabled, default: 0)",


From git at git.haskell.org  Fri Mar  2 22:35:01 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Fri,  2 Mar 2018 22:35:01 +0000 (UTC)
Subject: [commit: ghc] ghc-8.4: Adds *-cross-ncg flavour. (0454408)
Message-ID: <20180302223501.34E3B3A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : ghc-8.4
Link       : http://ghc.haskell.org/trac/ghc/changeset/0454408c3f64e7a8032060e71a15282c25264402/ghc

>---------------------------------------------------------------

commit 0454408c3f64e7a8032060e71a15282c25264402
Author: Moritz Angermann <moritz.angermann at gmail.com>
Date:   Fri Mar 2 16:15:09 2018 -0500

    Adds *-cross-ncg flavour.
    
    Our *-cross flavours force -fllvm, this adds flavours for cross
    compilation to x86_64, where we can use our native code generator.
    
    Test Plan: ./validate
    
    Reviewers: bgamari
    
    Reviewed By: bgamari
    
    Subscribers: rwbarton, thomie, carter
    
    Differential Revision: https://phabricator.haskell.org/D4443
    
    (cherry picked from commit e4dcebf899c796a13dabf8964038f78505b9f4ec)


>---------------------------------------------------------------

0454408c3f64e7a8032060e71a15282c25264402
 mk/build.mk.sample                                 | 17 +++++++++++++----
 mk/flavours/{bench-cross.mk => bench-cross-ncg.mk} |  4 ++--
 mk/flavours/{perf-cross.mk => perf-cross-ncg.mk}   |  4 ++--
 mk/flavours/{quick-cross.mk => quick-cross-ncg.mk} |  4 ++--
 4 files changed, 19 insertions(+), 10 deletions(-)

diff --git a/mk/build.mk.sample b/mk/build.mk.sample
index 958cea7..ce7b4d6 100644
--- a/mk/build.mk.sample
+++ b/mk/build.mk.sample
@@ -13,17 +13,23 @@
 # As above but build GHC using the LLVM backend
 #BuildFlavour = perf-llvm
 
-# Perf build configured for a cross-compiler
+# Perf build configured for a cross-compiler (using the LLVM backend)
 #BuildFlavour = perf-cross
 
+# Perf build configured for a cross-compiler (using the NCG backend)
+#BuildFlavour = perf-cross-ncg
+
 # Fast build with optimised libraries, no profiling (RECOMMENDED):
 #BuildFlavour = quick
 
 # Fast build with optimised libraries, no profiling, with LLVM:
 #BuildFlavour = quick-llvm
 
-# Fast build configured for a cross compiler
-#BuildFlavour  = quick-cross
+# Fast build configured for a cross compiler (using the LLVM backend)
+#BuildFlavour = quick-cross
+
+# Fast build configured for a cross compiler (using the NCG backend)
+#BuildFlavour = quick-cross-ncg
 
 # Even faster build.  NOT RECOMMENDED: the libraries will be
 # completely unoptimised, so any code built with this compiler
@@ -51,9 +57,12 @@
 # As above but build GHC using the LLVM backend
 #BuildFlavour = bench-llvm
 
-# Bench build configured for a cross-compiler
+# Bench build configured for a cross-compiler (using the LLVM backend)
 #BuildFlavour = bench-cross
 
+# Bench build configured for a cross-compiler (using the NCG backend)
+#BuildFlavour = bench-cross-ncg
+
 # Use the same settings as validate.
 #BuildFlavour = validate
 
diff --git a/mk/flavours/bench-cross.mk b/mk/flavours/bench-cross-ncg.mk
similarity index 85%
copy from mk/flavours/bench-cross.mk
copy to mk/flavours/bench-cross-ncg.mk
index ae67f34..6b686af 100644
--- a/mk/flavours/bench-cross.mk
+++ b/mk/flavours/bench-cross-ncg.mk
@@ -1,7 +1,7 @@
 SRC_HC_OPTS        = -O -H64m
 GhcStage1HcOpts    = -O
-GhcStage2HcOpts    = -O0 -fllvm
-GhcLibHcOpts       = -O2 -fllvm
+GhcStage2HcOpts    = -O0
+GhcLibHcOpts       = -O2
 BUILD_PROF_LIBS    = NO
 SplitObjs          = NO
 SplitSections      = NO
diff --git a/mk/flavours/perf-cross.mk b/mk/flavours/perf-cross-ncg.mk
similarity index 83%
copy from mk/flavours/perf-cross.mk
copy to mk/flavours/perf-cross-ncg.mk
index f202642..4b94c48 100644
--- a/mk/flavours/perf-cross.mk
+++ b/mk/flavours/perf-cross-ncg.mk
@@ -1,7 +1,7 @@
 SRC_HC_OPTS        = -O -H64m
 GhcStage1HcOpts    = -O2
-GhcStage2HcOpts    = -O2 -fllvm
-GhcLibHcOpts       = -O2 -fllvm
+GhcStage2HcOpts    = -O2
+GhcLibHcOpts       = -O2
 BUILD_PROF_LIBS    = YES
 #SplitObjs
 HADDOCK_DOCS       = NO
diff --git a/mk/flavours/quick-cross.mk b/mk/flavours/quick-cross-ncg.mk
similarity index 85%
copy from mk/flavours/quick-cross.mk
copy to mk/flavours/quick-cross-ncg.mk
index f0f00d2..97352cc 100644
--- a/mk/flavours/quick-cross.mk
+++ b/mk/flavours/quick-cross-ncg.mk
@@ -1,7 +1,7 @@
 SRC_HC_OPTS        = -O0 -H64m
 GhcStage1HcOpts    = -O
-GhcStage2HcOpts    = -O0 -fllvm
-GhcLibHcOpts       = -O -fllvm
+GhcStage2HcOpts    = -O0
+GhcLibHcOpts       = -O
 BUILD_PROF_LIBS    = NO
 SplitObjs          = NO
 SplitSections      = NO


From git at git.haskell.org  Fri Mar  2 22:35:04 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Fri,  2 Mar 2018 22:35:04 +0000 (UTC)
Subject: [commit: ghc] ghc-8.4: Update haddock submodule (004b76a)
Message-ID: <20180302223504.044503A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : ghc-8.4
Link       : http://ghc.haskell.org/trac/ghc/changeset/004b76a2da15270b9840fc381bc731694da0ec3b/ghc

>---------------------------------------------------------------

commit 004b76a2da15270b9840fc381bc731694da0ec3b
Author: Ben Gamari <ben at smart-cactus.org>
Date:   Sun Feb 25 17:12:44 2018 -0500

    Update haddock submodule
    
    Fixes file handle leak


>---------------------------------------------------------------

004b76a2da15270b9840fc381bc731694da0ec3b
 utils/haddock | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/utils/haddock b/utils/haddock
index d66092e..7a36a41 160000
--- a/utils/haddock
+++ b/utils/haddock
@@ -1 +1 @@
-Subproject commit d66092ee99639de628dbc4fce8a9936875f47d8c
+Subproject commit 7a36a41e154f9ff380b10584ec1a9f8bc4003be1


From git at git.haskell.org  Fri Mar  2 22:35:06 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Fri,  2 Mar 2018 22:35:06 +0000 (UTC)
Subject: [commit: ghc] ghc-8.4: configure: Enable LD_NO_GOLD is set in all
 codepaths (89c10eb)
Message-ID: <20180302223506.C90083A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : ghc-8.4
Link       : http://ghc.haskell.org/trac/ghc/changeset/89c10eb88e955b8abd28f85e342a4de501731e50/ghc

>---------------------------------------------------------------

commit 89c10eb88e955b8abd28f85e342a4de501731e50
Author: Ben Gamari <bgamari.foss at gmail.com>
Date:   Fri Mar 2 16:13:53 2018 -0500

    configure: Enable LD_NO_GOLD is set in all codepaths
    
    Test Plan: `./configure --disable-ld-override; make; make install`
    
    Reviewers: trofi, hvr
    
    Reviewed By: trofi
    
    Subscribers: rwbarton, thomie, erikd, carter, simonmar
    
    GHC Trac Issues: #14675
    
    Differential Revision: https://phabricator.haskell.org/D4448
    
    (cherry picked from commit bc1bcaa2c0c66fb247d1338d6d0055a833918a7f)


>---------------------------------------------------------------

89c10eb88e955b8abd28f85e342a4de501731e50
 aclocal.m4 | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/aclocal.m4 b/aclocal.m4
index cf93474..c02c1d1 100644
--- a/aclocal.m4
+++ b/aclocal.m4
@@ -2394,12 +2394,16 @@ AC_DEFUN([FIND_LD],[
 
         # Fallback
         AC_CHECK_TARGET_TOOL([LD], [ld])
+        # This isn't entirely safe since $LD may have been discovered to be
+        $ ld.gold, but what else can we do?
+        if test "x$LD_NO_GOLD" = "x"; then LD_NO_GOLD=$LD; fi
     }
 
     if test "x$enable_ld_override" = "xyes"; then
         find_ld
     else
         AC_CHECK_TARGET_TOOL([LD], [ld])
+        if test "x$LD_NO_GOLD" = "x"; then LD_NO_GOLD=$LD; fi
     fi
 
     CHECK_LD_COPY_BUG([$1])


From git at git.haskell.org  Fri Mar  2 22:35:09 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Fri,  2 Mar 2018 22:35:09 +0000 (UTC)
Subject: [commit: ghc] ghc-8.4: Various documentation improvements (a666e43)
Message-ID: <20180302223509.91CFE3A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : ghc-8.4
Link       : http://ghc.haskell.org/trac/ghc/changeset/a666e43200d88a847d751a62c90f502e0c90e9ff/ghc

>---------------------------------------------------------------

commit a666e43200d88a847d751a62c90f502e0c90e9ff
Author: Sergey Vinokurov <serg.foo at gmail.com>
Date:   Wed Feb 7 21:10:17 2018 +0000

    Various documentation improvements
    
     * Fix missing code example in changelog for 8.4.1
    
     * List 'setEnv' as opposite of 'getEnv'
    
       It seems best to direct users to use 'System.Environment.setEnv'
       rather than 'System.Posix.Env.putEnv'. This is due to 'setEnv' being
       located in the same module as 'getEnv' and my virtue of working on
       Windows platform, whereas 'putEnv' does not have that quality because
       it's part of the 'unix' package.
    
     * Reflect in docs the fact that 'readMVar' is not a composition of
       'takeMVVar' and 'putMVar' any more
    
    (cherry picked from commit df449e1744d59eef7f41e09196629bc01815e984)


>---------------------------------------------------------------

a666e43200d88a847d751a62c90f502e0c90e9ff
 libraries/base/Control/Concurrent/MVar.hs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/libraries/base/Control/Concurrent/MVar.hs b/libraries/base/Control/Concurrent/MVar.hs
index 393fca8..fa99361 100644
--- a/libraries/base/Control/Concurrent/MVar.hs
+++ b/libraries/base/Control/Concurrent/MVar.hs
@@ -41,8 +41,8 @@
 -- atomic operations such as reading from multiple variables: use 'STM'
 -- instead.
 --
--- In particular, the "bigger" functions in this module ('readMVar',
--- 'swapMVar', 'withMVar', 'modifyMVar_' and 'modifyMVar') are simply
+-- In particular, the "bigger" functions in this module ('swapMVar',
+-- 'withMVar', 'modifyMVar_' and 'modifyMVar') are simply
 -- the composition of a 'takeMVar' followed by a 'putMVar' with
 -- exception safety.
 -- These only have atomicity guarantees if all other threads


From git at git.haskell.org  Fri Mar  2 22:53:42 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Fri,  2 Mar 2018 22:53:42 +0000 (UTC)
Subject: [commit: ghc] wip/T2893: Test Trac #14863 (32e8499)
Message-ID: <20180302225342.2BDD43A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/T2893
Link       : http://ghc.haskell.org/trac/ghc/changeset/32e8499889d314e9efd0747b4053290a2dc237d5/ghc

>---------------------------------------------------------------

commit 32e8499889d314e9efd0747b4053290a2dc237d5
Author: Simon Peyton Jones <simonpj at microsoft.com>
Date:   Fri Mar 2 22:53:27 2018 +0000

    Test Trac #14863


>---------------------------------------------------------------

32e8499889d314e9efd0747b4053290a2dc237d5
 testsuite/tests/quantified-constraints/T14863.hs | 27 ++++++++++++++++++++++++
 testsuite/tests/quantified-constraints/all.T     |  1 +
 2 files changed, 28 insertions(+)

diff --git a/testsuite/tests/quantified-constraints/T14863.hs b/testsuite/tests/quantified-constraints/T14863.hs
new file mode 100644
index 0000000..c74b818
--- /dev/null
+++ b/testsuite/tests/quantified-constraints/T14863.hs
@@ -0,0 +1,27 @@
+{-# LANGUAGE ConstraintKinds #-}
+{-# LANGUAGE FlexibleContexts #-}
+{-# LANGUAGE FlexibleInstances #-}
+{-# LANGUAGE GADTs #-}
+{-# LANGUAGE ImpredicativeTypes #-}
+{-# LANGUAGE MultiParamTypeClasses #-}
+{-# LANGUAGE QuantifiedConstraints #-}
+{-# LANGUAGE UndecidableInstances #-}
+module T14863 where
+
+data Dict c where
+  Dict :: c => Dict c
+
+class    (a => b) => Implies a b
+instance (a => b) => Implies a b
+
+uncurryCImpredic1 :: forall a b c. Implies a (b => c) => Dict (Implies (a, b) c)
+uncurryCImpredic1 = Dict
+
+uncurryCImpredic2 :: forall a b c. a => Implies b c => Dict (Implies (a, b) c)
+uncurryCImpredic2 = Dict
+
+uncurryC1 :: forall a b c. (a => b => c) => Dict (Implies (a, b) c)
+uncurryC1 = Dict
+
+uncurryC2 :: forall a b c. Implies a (Implies b c) => Dict (Implies (a, b) c)
+uncurryC2 = Dict
\ No newline at end of file
diff --git a/testsuite/tests/quantified-constraints/all.T b/testsuite/tests/quantified-constraints/all.T
index db1c6ba..4f63911 100644
--- a/testsuite/tests/quantified-constraints/all.T
+++ b/testsuite/tests/quantified-constraints/all.T
@@ -5,6 +5,7 @@ test('T2893', normal, compile, [''])
 test('T2893a', normal, compile, [''])
 test('T2893c', normal, compile, [''])
 test('T9123', normal, compile, [''])
+test('T14863', normal, compile, [''])
 
 # Not yet
 # test('T9123a', normal, compile, [''])


From git at git.haskell.org  Sat Mar  3 18:52:01 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Sat,  3 Mar 2018 18:52:01 +0000 (UTC)
Subject: [commit: ghc] master: Parenthesize (() :: Constraint) in argument
 position (99c556d)
Message-ID: <20180303185201.C95AD3A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/99c556d2bb0594fd718622906168d2ea25a0bf06/ghc

>---------------------------------------------------------------

commit 99c556d2bb0594fd718622906168d2ea25a0bf06
Author: Ryan Scott <ryan.gl.scott at gmail.com>
Date:   Sat Mar 3 13:48:38 2018 -0500

    Parenthesize (() :: Constraint) in argument position
    
    Summary:
    A simple oversight in the pretty-printer lead to a special
    case for `() :: Constraint` not being parenthesized correctly when
    used in an argument position. Easily fixed with a `maybeParen`.
    
    Test Plan: make test TEST=T14796
    
    Reviewers: alanz, goldfire, bgamari, simonpj
    
    Reviewed By: bgamari, simonpj
    
    Subscribers: simonpj, rwbarton, thomie, carter
    
    GHC Trac Issues: #14796
    
    Differential Revision: https://phabricator.haskell.org/D4408


>---------------------------------------------------------------

99c556d2bb0594fd718622906168d2ea25a0bf06
 compiler/iface/IfaceType.hs                | 15 ++++++++-------
 testsuite/tests/ghci/scripts/T14796.script |  3 +++
 testsuite/tests/ghci/scripts/T14796.stdout |  1 +
 testsuite/tests/ghci/scripts/all.T         |  1 +
 4 files changed, 13 insertions(+), 7 deletions(-)

diff --git a/compiler/iface/IfaceType.hs b/compiler/iface/IfaceType.hs
index 62b33cd..0c5922e 100644
--- a/compiler/iface/IfaceType.hs
+++ b/compiler/iface/IfaceType.hs
@@ -595,7 +595,7 @@ ppr_ty :: TyPrec -> IfaceType -> SDoc
 ppr_ty _         (IfaceFreeTyVar tyvar) = ppr tyvar  -- This is the main reson for IfaceFreeTyVar!
 ppr_ty _         (IfaceTyVar tyvar)     = ppr tyvar  -- See Note [TcTyVars in IfaceType]
 ppr_ty ctxt_prec (IfaceTyConApp tc tys) = pprTyTcApp ctxt_prec tc tys
-ppr_ty _         (IfaceTupleTy i p tys) = pprTuple i p tys
+ppr_ty ctxt_prec (IfaceTupleTy i p tys) = pprTuple ctxt_prec i p tys
 ppr_ty _         (IfaceLitTy n)         = pprIfaceTyLit n
         -- Function types
 ppr_ty ctxt_prec (IfaceFunTy ty1 ty2)
@@ -889,7 +889,7 @@ pprTyTcApp' ctxt_prec tc tys dflags style
   | IfaceTupleTyCon arity sort <- ifaceTyConSort info
   , not (debugStyle style)
   , arity == ifaceVisTcArgsLength tys
-  = pprTuple sort (ifaceTyConIsPromoted info) tys
+  = pprTuple ctxt_prec sort (ifaceTyConIsPromoted info) tys
 
   | IfaceSumTyCon arity <- ifaceTyConSort info
   = pprSum arity (ifaceTyConIsPromoted info) tys
@@ -1017,18 +1017,19 @@ pprSum _arity is_promoted args
     in pprPromotionQuoteI is_promoted
        <> sumParens (pprWithBars (ppr_ty TopPrec) args')
 
-pprTuple :: TupleSort -> IsPromoted -> IfaceTcArgs -> SDoc
-pprTuple ConstraintTuple IsNotPromoted ITC_Nil
-  = text "() :: Constraint"
+pprTuple :: TyPrec -> TupleSort -> IsPromoted -> IfaceTcArgs -> SDoc
+pprTuple ctxt_prec ConstraintTuple IsNotPromoted ITC_Nil
+  = maybeParen ctxt_prec TyConPrec $
+    text "() :: Constraint"
 
 -- All promoted constructors have kind arguments
-pprTuple sort IsPromoted args
+pprTuple _ sort IsPromoted args
   = let tys = tcArgsIfaceTypes args
         args' = drop (length tys `div` 2) tys
     in pprPromotionQuoteI IsPromoted <>
        tupleParens sort (pprWithCommas pprIfaceType args')
 
-pprTuple sort promoted args
+pprTuple _ sort promoted args
   =   -- drop the RuntimeRep vars.
       -- See Note [Unboxed tuple RuntimeRep vars] in TyCon
     let tys   = tcArgsIfaceTypes args
diff --git a/testsuite/tests/ghci/scripts/T14796.script b/testsuite/tests/ghci/scripts/T14796.script
new file mode 100644
index 0000000..9a85d44
--- /dev/null
+++ b/testsuite/tests/ghci/scripts/T14796.script
@@ -0,0 +1,3 @@
+:set -XGADTs -XConstraintKinds -XTypeApplications
+data ECC ctx f a where ECC :: ctx => f a -> ECC ctx f a
+:t ECC @() @[] @()
diff --git a/testsuite/tests/ghci/scripts/T14796.stdout b/testsuite/tests/ghci/scripts/T14796.stdout
new file mode 100644
index 0000000..c8bb219
--- /dev/null
+++ b/testsuite/tests/ghci/scripts/T14796.stdout
@@ -0,0 +1 @@
+ECC @() @[] @() :: [()] -> ECC (() :: Constraint) [] ()
diff --git a/testsuite/tests/ghci/scripts/all.T b/testsuite/tests/ghci/scripts/all.T
index 997203f..dcce723 100755
--- a/testsuite/tests/ghci/scripts/all.T
+++ b/testsuite/tests/ghci/scripts/all.T
@@ -264,3 +264,4 @@ test('T13963', normal, ghci_script, ['T13963.script'])
 test('T14342', [extra_hc_opts("-XOverloadedStrings -XRebindableSyntax")],
                ghci_script, ['T14342.script'])
 test('T14676', extra_files(['../prog002']), ghci_script, ['T14676.script'])
+test('T14796', normal, ghci_script, ['T14796.script'])


From git at git.haskell.org  Sun Mar  4 02:39:39 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Sun,  4 Mar 2018 02:39:39 +0000 (UTC)
Subject: [commit: ghc] master: Bump hsc2hs submodule (4631ceb)
Message-ID: <20180304023939.46C8F3A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/4631ceb261cb08756b955c6b495d5e719d35ab62/ghc

>---------------------------------------------------------------

commit 4631ceb261cb08756b955c6b495d5e719d35ab62
Author: Moritz Angermann <moritz.angermann at gmail.com>
Date:   Sun Mar 4 10:37:58 2018 +0800

    Bump hsc2hs submodule
    
    This should have been part of 5f6fcf78.


>---------------------------------------------------------------

4631ceb261cb08756b955c6b495d5e719d35ab62
 utils/hsc2hs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/utils/hsc2hs b/utils/hsc2hs
index 738f366..b858803 160000
--- a/utils/hsc2hs
+++ b/utils/hsc2hs
@@ -1 +1 @@
-Subproject commit 738f3666c878ee9e79c3d5e819ef8b3460288edf
+Subproject commit b8588039f3810e2d0f52e9afdb15998992ee38b1


From git at git.haskell.org  Sun Mar  4 02:51:05 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Sun,  4 Mar 2018 02:51:05 +0000 (UTC)
Subject: [commit: ghc] master: Bump Cabal submodule to 2.2 (8f0b2f5)
Message-ID: <20180304025105.3C3323A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/8f0b2f5eadf0fcb47c581907205a9db686214a69/ghc

>---------------------------------------------------------------

commit 8f0b2f5eadf0fcb47c581907205a9db686214a69
Author: Moritz Angermann <moritz.angermann at gmail.com>
Date:   Sat Mar 3 16:16:41 2018 -0500

    Bump Cabal submodule to 2.2
    
    Requires some ghc-cabal changes as well.
    
    Test Plan: ./validate
    
    Reviewers: hvr, bgamari
    
    Reviewed By: bgamari
    
    Subscribers: hsyl20, erikd, alpmestan, rwbarton, thomie, carter
    
    Differential Revision: https://phabricator.haskell.org/D4453


>---------------------------------------------------------------

8f0b2f5eadf0fcb47c581907205a9db686214a69
 libraries/Cabal                                    |  2 +-
 libraries/base/configure.ac                        |  4 +--
 rules/build-package.mk                             |  2 +-
 testsuite/tests/driver/T4437.hs                    |  1 +
 .../check-api-annotations.cabal                    |  2 +-
 utils/check-ppr/check-ppr.cabal                    |  2 +-
 utils/ghc-cabal/Main.hs                            | 31 ++++++++++++++++++----
 utils/ghc-cabal/ghc-cabal.cabal                    |  2 +-
 utils/ghctags/ghctags.cabal                        |  2 +-
 9 files changed, 35 insertions(+), 13 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc 8f0b2f5eadf0fcb47c581907205a9db686214a69

From git at git.haskell.org  Sun Mar  4 16:16:51 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Sun,  4 Mar 2018 16:16:51 +0000 (UTC)
Subject: [commit: ghc] master: Bump Cabal submodule (a9f680f)
Message-ID: <20180304161651.24FCA3A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/a9f680f631e20104661e357393f9704e2f8ba234/ghc

>---------------------------------------------------------------

commit a9f680f631e20104661e357393f9704e2f8ba234
Author: Ben Gamari <ben at smart-cactus.org>
Date:   Sat Mar 3 22:05:44 2018 -0500

    Bump Cabal submodule


>---------------------------------------------------------------

a9f680f631e20104661e357393f9704e2f8ba234
 libraries/Cabal | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libraries/Cabal b/libraries/Cabal
index 98a72c9..7ce486e 160000
--- a/libraries/Cabal
+++ b/libraries/Cabal
@@ -1 +1 @@
-Subproject commit 98a72c9da6f56a9917b66d7532df755719ec7a25
+Subproject commit 7ce486e6553d24877ae3b23868b95d20bf83760a


From git at git.haskell.org  Sun Mar  4 16:16:53 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Sun,  4 Mar 2018 16:16:53 +0000 (UTC)
Subject: [commit: ghc] ghc-8.4: Bump Cabal submodule to 2.2 (c760ae3)
Message-ID: <20180304161653.EF6023A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : ghc-8.4
Link       : http://ghc.haskell.org/trac/ghc/changeset/c760ae373d47a16170dab0b9ed6f1680a75d4263/ghc

>---------------------------------------------------------------

commit c760ae373d47a16170dab0b9ed6f1680a75d4263
Author: Moritz Angermann <moritz.angermann at gmail.com>
Date:   Sat Mar 3 16:16:41 2018 -0500

    Bump Cabal submodule to 2.2
    
    Requires some ghc-cabal changes as well.
    
    Test Plan: ./validate
    
    Reviewers: hvr, bgamari
    
    Reviewed By: bgamari
    
    Subscribers: hsyl20, erikd, alpmestan, rwbarton, thomie, carter
    
    Differential Revision: https://phabricator.haskell.org/D4453


>---------------------------------------------------------------

c760ae373d47a16170dab0b9ed6f1680a75d4263
 libraries/Cabal                                    |  2 +-
 libraries/base/configure.ac                        |  4 +--
 rules/build-package.mk                             |  2 +-
 .../check-api-annotations.cabal                    |  2 +-
 utils/check-ppr/check-ppr.cabal                    |  2 +-
 utils/ghc-cabal/Main.hs                            | 31 ++++++++++++++++++----
 utils/ghc-cabal/ghc-cabal.cabal                    |  2 +-
 utils/ghctags/ghctags.cabal                        |  2 +-
 utils/haddock                                      |  2 +-
 9 files changed, 35 insertions(+), 14 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc c760ae373d47a16170dab0b9ed6f1680a75d4263

From git at git.haskell.org  Mon Mar  5 07:44:04 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon,  5 Mar 2018 07:44:04 +0000 (UTC)
Subject: [commit: ghc] branch 'wip/angerman/win32-cross-2' created
Message-ID: <20180305074404.821783A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

New branch : wip/angerman/win32-cross-2
Referencing: b824438e1c6a203f7175705161852928d4315329

From git at git.haskell.org  Mon Mar  5 07:44:17 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon,  5 Mar 2018 07:44:17 +0000 (UTC)
Subject: [commit: ghc] wip/angerman/win32-cross-2: adds .gitignore (9b0ac82)
Message-ID: <20180305074417.385653A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/angerman/win32-cross-2
Link       : http://ghc.haskell.org/trac/ghc/changeset/9b0ac8207c590104129c49bd10d6649ec8a58f01/ghc

>---------------------------------------------------------------

commit 9b0ac8207c590104129c49bd10d6649ec8a58f01
Author: Moritz Angermann <moritz.angermann at gmail.com>
Date:   Thu Feb 15 13:54:55 2018 +0800

    adds .gitignore


>---------------------------------------------------------------

9b0ac8207c590104129c49bd10d6649ec8a58f01
 .gitignore | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/.gitignore b/.gitignore
index 460cb68..4d815d7 100644
--- a/.gitignore
+++ b/.gitignore
@@ -81,8 +81,7 @@ _darcs/
 /ghc/stage1/
 /ghc/stage2/
 /ghc/stage3/
-/iserv/stage2*/
-/iserv/dist/
+/utils/iserv/stage2*/
 
 # -----------------------------------------------------------------------------
 # specific generated files


From git at git.haskell.org  Mon Mar  5 07:44:07 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon,  5 Mar 2018 07:44:07 +0000 (UTC)
Subject: [commit: ghc] wip/angerman/win32-cross-2: Move `iserv` into `utils`
 and change package name from `iserv-bin` to `iserv` (b824438)
Message-ID: <20180305074407.5CB953A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/angerman/win32-cross-2
Link       : http://ghc.haskell.org/trac/ghc/changeset/b824438e1c6a203f7175705161852928d4315329/ghc

>---------------------------------------------------------------

commit b824438e1c6a203f7175705161852928d4315329
Author: Moritz Angermann <moritz.angermann at gmail.com>
Date:   Thu Feb 22 16:53:35 2018 +0800

    Move `iserv` into `utils` and change package name from `iserv-bin` to `iserv`
    
    Summary:
    This is done for consistency. We usually call the package file the same name the
    folder has.  The move into `utils` is done so that we can move the library into
    `libraries/iserv` and the proxy into `utils/iserv-proxy` and then break the
    `iserv.cabal` apart.  This will make building the cross compiler with TH
    simpler, because we can build the library and proxy as separate packages.
    
    Test Plan: ./validate
    
    Reviewers: bgamari, goldfire, erikd
    
    Subscribers: rwbarton, thomie, carter
    
    Differential Revision: https://phabricator.haskell.org/D4436


>---------------------------------------------------------------

b824438e1c6a203f7175705161852928d4315329
 libraries/libiserv/src/Main.hs | 63 ------------------------------------------
 1 file changed, 63 deletions(-)

diff --git a/libraries/libiserv/src/Main.hs b/libraries/libiserv/src/Main.hs
deleted file mode 100644
index 858cee8..0000000
--- a/libraries/libiserv/src/Main.hs
+++ /dev/null
@@ -1,63 +0,0 @@
-{-# LANGUAGE CPP, GADTs #-}
-
--- |
--- The Remote GHCi server.
---
--- For details on Remote GHCi, see Note [Remote GHCi] in
--- compiler/ghci/GHCi.hs.
---
-module Main (main) where
-
-import Lib (serv)
-
-import GHCi.Message
-import GHCi.Signals
-import GHCi.Utils
-
-import Control.Exception
-import Control.Monad
-import Data.IORef
-import System.Environment
-import System.Exit
-import Text.Printf
-
-dieWithUsage :: IO a
-dieWithUsage = do
-    prog <- getProgName
-    die $ prog ++ ": " ++ msg
-  where
-#ifdef WINDOWS
-    msg = "usage: iserv <write-handle> <read-handle> [-v]"
-#else
-    msg = "usage: iserv <write-fd> <read-fd> [-v]"
-#endif
-
-main :: IO ()
-main = do
-  args <- getArgs
-  (wfd1, rfd2, rest) <-
-      case args of
-        arg0:arg1:rest -> do
-            let wfd1 = read arg0
-                rfd2 = read arg1
-            return (wfd1, rfd2, rest)
-        _ -> dieWithUsage
-
-  verbose <- case rest of
-    ["-v"] -> return True
-    []     -> return False
-    _      -> dieWithUsage
-  when verbose $
-    printf "GHC iserv starting (in: %d; out: %d)\n"
-      (fromIntegral rfd2 :: Int) (fromIntegral wfd1 :: Int)
-  inh  <- getGhcHandle rfd2
-  outh <- getGhcHandle wfd1
-  installSignalHandlers
-  lo_ref <- newIORef Nothing
-  let pipe = Pipe{pipeRead = inh, pipeWrite = outh, pipeLeftovers = lo_ref}
-  uninterruptibleMask $ serv verbose hook pipe
-
-  where hook = return -- empty hook
-    -- we cannot allow any async exceptions while communicating, because
-    -- we will lose sync in the protocol, hence uninterruptibleMask.
-


From git at git.haskell.org  Mon Mar  5 07:44:11 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon,  5 Mar 2018 07:44:11 +0000 (UTC)
Subject: [commit: ghc] wip/angerman/win32-cross-2: Move `iserv` into `utils`
 and change package name from `iserv-bin` to `iserv` (da04151)
Message-ID: <20180305074411.908B83A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/angerman/win32-cross-2
Link       : http://ghc.haskell.org/trac/ghc/changeset/da04151672629e258a0f27134b544c8d5379fba2/ghc

>---------------------------------------------------------------

commit da04151672629e258a0f27134b544c8d5379fba2
Author: Moritz Angermann <moritz.angermann at gmail.com>
Date:   Sat Nov 25 15:10:52 2017 +0800

    Move `iserv` into `utils` and change package name from `iserv-bin` to `iserv`
    
    This is done for consistency. We usually call the package file the same name the
    folder has.  The move into `utils` is done so that we can move the library into
    `libraries/iserv` and the proxy into `utils/iserv-proxy` and then break the
    `iserv.cabal` apart.  This will make building the cross compiler with TH
    simpler, because we can build the library and proxy as separate packages.
    
    # Conflicts:
    #	utils/iserv-proxy/iserv-proxy.cabal


>---------------------------------------------------------------

da04151672629e258a0f27134b544c8d5379fba2
 ghc.mk                                             |  13 +--
 {iserv => libraries/libiserv}/Makefile             |   0
 {iserv => libraries/libiserv}/cbits/iservmain.c    |   0
 libraries/libiserv/ghc.mk                          |   5 +
 libraries/libiserv/libiserv.cabal                  |  39 +++++++
 {iserv => libraries/libiserv}/proxy-src/Remote.hs  |   0
 {iserv => libraries/libiserv}/src/GHCi/Utils.hsc   |   0
 {iserv => libraries/libiserv}/src/Lib.hs           |   0
 {iserv => libraries/libiserv}/src/Main.hs          |   0
 .../libiserv}/src/Remote/Message.hs                |   0
 {iserv => libraries/libiserv}/src/Remote/Slave.hs  |   0
 {iserv => utils/iserv-proxy}/Makefile              |   0
 utils/iserv-proxy/ghc.mk                           | 113 +++++++++++++++++++++
 .../iserv-proxy/iserv-proxy.cabal                  |  72 +------------
 .../Remote.hs => utils/iserv-proxy/src/Main.hs     |   0
 {iserv => utils/iserv}/Makefile                    |   0
 {iserv => utils/iserv}/cbits/iservmain.c           |   0
 {iserv => utils/iserv}/ghc.mk                      |  66 ++++++------
 utils/iserv/iserv.cabal                            |  44 ++++++++
 {iserv => utils/iserv}/src/Main.hs                 |   0
 20 files changed, 246 insertions(+), 106 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc da04151672629e258a0f27134b544c8d5379fba2

From git at git.haskell.org  Mon Mar  5 07:44:14 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon,  5 Mar 2018 07:44:14 +0000 (UTC)
Subject: [commit: ghc] wip/angerman/win32-cross-2: temp fix Makefile (c2a32ce)
Message-ID: <20180305074414.6341C3A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/angerman/win32-cross-2
Link       : http://ghc.haskell.org/trac/ghc/changeset/c2a32ce598b0c4df875a617f5e458b0549560eaf/ghc

>---------------------------------------------------------------

commit c2a32ce598b0c4df875a617f5e458b0549560eaf
Author: Moritz Angermann <moritz.angermann at gmail.com>
Date:   Thu Feb 15 12:29:14 2018 +0800

    temp fix Makefile


>---------------------------------------------------------------

c2a32ce598b0c4df875a617f5e458b0549560eaf
 utils/iserv/Makefile | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/utils/iserv/Makefile b/utils/iserv/Makefile
index f160978..3619858 100644
--- a/utils/iserv/Makefile
+++ b/utils/iserv/Makefile
@@ -10,6 +10,6 @@
 #
 # -----------------------------------------------------------------------------
 
-dir = iserv
-TOP = ..
+dir = utils/iserv
+TOP = ../..
 include $(TOP)/mk/sub-makefile.mk


From git at git.haskell.org  Mon Mar  5 08:51:11 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon,  5 Mar 2018 08:51:11 +0000 (UTC)
Subject: [commit: ghc] master: Wombling around in Trac #14808 (e7653bc)
Message-ID: <20180305085111.2F91E3A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/e7653bc3c4f57d2282e982b9eb83bd1fcbae6e30/ghc

>---------------------------------------------------------------

commit e7653bc3c4f57d2282e982b9eb83bd1fcbae6e30
Author: Simon Peyton Jones <simonpj at microsoft.com>
Date:   Fri Mar 2 17:12:03 2018 +0000

    Wombling around in Trac #14808
    
    Comment:4 in Trac #14808 explains why I'm unhappy with the current
    state of affairs -- at least the lack of documentation.
    
    This smallpatch does nothing major:
    
    * adds comments
    * uses existing type synonyms more (notably FreeKiTyVarsWithDups)
    * adds another test case to T14808


>---------------------------------------------------------------

e7653bc3c4f57d2282e982b9eb83bd1fcbae6e30
 compiler/rename/RnSource.hs    |  9 ++++++---
 compiler/rename/RnTypes.hs     | 35 +++++++++++++++++++++--------------
 testsuite/tests/gadt/T14808.hs |  6 ++++++
 3 files changed, 33 insertions(+), 17 deletions(-)

diff --git a/compiler/rename/RnSource.hs b/compiler/rename/RnSource.hs
index 5c7f538..447871a 100644
--- a/compiler/rename/RnSource.hs
+++ b/compiler/rename/RnSource.hs
@@ -1917,9 +1917,12 @@ rnConDecl decl@(ConDeclGADT { con_names   = names
         ; let explicit_tkvs = hsQTvExplicit qtvs
               theta         = hsConDeclTheta mcxt
               arg_tys       = hsConDeclArgTys args
-                       -- We must ensure that we extract the free tkvs in the
-                       -- order of theta, then arg_tys, then res_ty. Failing to
-                       -- do so resulted in #14808.
+
+          -- We must ensure that we extract the free tkvs in left-to-right
+          -- order of their appearance in the constructor type.
+          -- That order governs the order the implicitly-quantified type
+          -- variable, and hence the order needed for visible type application
+          -- See Trac #14808.
         ; free_tkvs <- extractHsTysRdrTyVarsDups (theta ++ arg_tys ++ [res_ty])
         ; free_tkvs <- extractHsTvBndrs explicit_tkvs free_tkvs
 
diff --git a/compiler/rename/RnTypes.hs b/compiler/rename/RnTypes.hs
index cdb98fb..2305a04 100644
--- a/compiler/rename/RnTypes.hs
+++ b/compiler/rename/RnTypes.hs
@@ -1748,27 +1748,32 @@ extractDataDefnKindVars (HsDataDefn { dd_ctxt = ctxt, dd_kindSig = ksig
         extract_mlctxt ctxt =<<
         extract_ltys TypeLevel (hsConDeclArgTys args) emptyFKTV
 
-extract_mlctxt :: Maybe (LHsContext GhcPs) -> FreeKiTyVars -> RnM FreeKiTyVars
+extract_mlctxt :: Maybe (LHsContext GhcPs)
+               -> FreeKiTyVarsWithDups -> RnM FreeKiTyVarsWithDups
 extract_mlctxt Nothing     acc = return acc
 extract_mlctxt (Just ctxt) acc = extract_lctxt TypeLevel ctxt acc
 
 extract_lctxt :: TypeOrKind
-              -> LHsContext GhcPs -> FreeKiTyVars -> RnM FreeKiTyVars
+              -> LHsContext GhcPs
+              -> FreeKiTyVarsWithDups -> RnM FreeKiTyVarsWithDups
 extract_lctxt t_or_k ctxt = extract_ltys t_or_k (unLoc ctxt)
 
 extract_ltys :: TypeOrKind
-             -> [LHsType GhcPs] -> FreeKiTyVars -> RnM FreeKiTyVars
+             -> [LHsType GhcPs]
+             -> FreeKiTyVarsWithDups -> RnM FreeKiTyVarsWithDups
 extract_ltys t_or_k tys acc = foldrM (extract_lty t_or_k) acc tys
 
-extract_mb :: (a -> FreeKiTyVars -> RnM FreeKiTyVars)
-           -> Maybe a -> FreeKiTyVars -> RnM FreeKiTyVars
+extract_mb :: (a -> FreeKiTyVarsWithDups -> RnM FreeKiTyVarsWithDups)
+           -> Maybe a
+           -> FreeKiTyVarsWithDups -> RnM FreeKiTyVarsWithDups
 extract_mb _ Nothing  acc = return acc
 extract_mb f (Just x) acc = f x acc
 
 extract_lkind :: LHsType GhcPs -> FreeKiTyVars -> RnM FreeKiTyVars
 extract_lkind = extract_lty KindLevel
 
-extract_lty :: TypeOrKind -> LHsType GhcPs -> FreeKiTyVars -> RnM FreeKiTyVars
+extract_lty :: TypeOrKind -> LHsType GhcPs
+            -> FreeKiTyVarsWithDups -> RnM FreeKiTyVarsWithDups
 extract_lty t_or_k (L _ ty) acc
   = case ty of
       HsTyVar _  ltv            -> extract_tv t_or_k ltv acc
@@ -1813,19 +1818,21 @@ extract_apps :: TypeOrKind
              -> [LHsAppType GhcPs] -> FreeKiTyVars -> RnM FreeKiTyVars
 extract_apps t_or_k tys acc = foldrM (extract_app t_or_k) acc tys
 
-extract_app :: TypeOrKind -> LHsAppType GhcPs -> FreeKiTyVars
-            -> RnM FreeKiTyVars
+extract_app :: TypeOrKind -> LHsAppType GhcPs
+            -> FreeKiTyVarsWithDups -> RnM FreeKiTyVarsWithDups
 extract_app t_or_k (L _ (HsAppInfix tv))  acc = extract_tv t_or_k tv acc
 extract_app t_or_k (L _ (HsAppPrefix ty)) acc = extract_lty t_or_k ty acc
 
 extractHsTvBndrs :: [LHsTyVarBndr GhcPs]
-                 -> FreeKiTyVars           -- Free in body
-                 -> RnM FreeKiTyVars       -- Free in result
+                 -> FreeKiTyVarsWithDups           -- Free in body
+                 -> RnM FreeKiTyVarsWithDups       -- Free in result
 extractHsTvBndrs tv_bndrs body_fvs
   = extract_hs_tv_bndrs tv_bndrs emptyFKTV body_fvs
 
-extract_hs_tv_bndrs :: [LHsTyVarBndr GhcPs] -> FreeKiTyVars
-                    -> FreeKiTyVars -> RnM FreeKiTyVars
+extract_hs_tv_bndrs :: [LHsTyVarBndr GhcPs]
+                    -> FreeKiTyVarsWithDups  -- Accumulator
+                    -> FreeKiTyVarsWithDups  -- Free in body
+                    -> RnM FreeKiTyVarsWithDups
 -- In (forall (a :: Maybe e). a -> b) we have
 --     'a' is bound by the forall
 --     'b' is a free type variable
@@ -1866,8 +1873,8 @@ extract_hs_tv_bndrs_kvs tv_bndrs
        ; return (freeKiTyVarsKindVars fktvs) }
          -- There will /be/ no free tyvars!
 
-extract_tv :: TypeOrKind -> Located RdrName -> FreeKiTyVars
-           -> RnM FreeKiTyVars
+extract_tv :: TypeOrKind -> Located RdrName
+           -> FreeKiTyVarsWithDups -> RnM FreeKiTyVarsWithDups
 extract_tv t_or_k ltv@(L _ tv) acc@(FKTV kvs tvs)
   | not (isRdrTyVar tv) = return acc
   | isTypeLevel t_or_k  = return (FKTV kvs (ltv : tvs))
diff --git a/testsuite/tests/gadt/T14808.hs b/testsuite/tests/gadt/T14808.hs
index 726f502..da3d521 100644
--- a/testsuite/tests/gadt/T14808.hs
+++ b/testsuite/tests/gadt/T14808.hs
@@ -10,3 +10,9 @@ data ECC ctx f a where
 
 f :: [()] -> ECC () [] ()
 f = ECC @() @[] @()
+
+data ECC2 f a ctx where
+  ECC2 :: ctx => f a -> ECC2 f a ctx
+
+f2 :: [()] -> ECC2 [] () ()
+f2 = ECC2 @() @[] @()


From git at git.haskell.org  Mon Mar  5 08:51:14 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon,  5 Mar 2018 08:51:14 +0000 (UTC)
Subject: [commit: ghc] master: Respect Note [The tcType invariant] (3d25203)
Message-ID: <20180305085114.94F733A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/3d252037234ce48f9bdada7d5c9b1d8eba470829/ghc

>---------------------------------------------------------------

commit 3d252037234ce48f9bdada7d5c9b1d8eba470829
Author: Simon Peyton Jones <simonpj at microsoft.com>
Date:   Fri Mar 2 17:26:58 2018 +0000

    Respect Note [The tcType invariant]
    
    I tried to do this with
    
        commit 0a12d92a8f65d374f9317af2759af2b46267ad5c
        Author: Simon Peyton Jones <simonpj at microsoft.com>
        Date:   Wed Dec 13 12:53:26 2017 +0000
    
        Further improvements to well-kinded types
    
        The typechecker has the invariant that every type should be well-kinded
        as it stands, without zonking.  See Note [The well-kinded type invariant]
        in TcType.
    
        That invariant was not being upheld, which led to Trac #14174.  I fixed
        part of it, but T14174a showed that there was more.  This patch finishes
        the job.
    
    But I didn't get it quite right as Trac #14873 showed.
    
    This patch fixes the problem; although I am still a bit unhappy.
    (See "A worry" in the HsApp case of tc_infer_hs_type.)


>---------------------------------------------------------------

3d252037234ce48f9bdada7d5c9b1d8eba470829
 compiler/typecheck/TcHsType.hs      | 59 ++++++++++++++++++++++++++++---------
 testsuite/tests/polykinds/T14873.hs | 49 ++++++++++++++++++++++++++++++
 testsuite/tests/polykinds/all.T     |  1 +
 3 files changed, 95 insertions(+), 14 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc 3d252037234ce48f9bdada7d5c9b1d8eba470829

From git at git.haskell.org  Mon Mar  5 14:00:16 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon,  5 Mar 2018 14:00:16 +0000 (UTC)
Subject: [commit: ghc] master: Fix #14888 by adding more special cases for
 ArrowT (6ee831f)
Message-ID: <20180305140016.561A33A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/6ee831f279c91888ee5815f8eee473bcd6fd25c6/ghc

>---------------------------------------------------------------

commit 6ee831f279c91888ee5815f8eee473bcd6fd25c6
Author: Ryan Scott <ryan.gl.scott at gmail.com>
Date:   Mon Mar 5 08:57:04 2018 -0500

    Fix #14888 by adding more special cases for ArrowT
    
    Summary:
    There were previously some situations where `(->)` would
    not be desugared or reified as `ArrowT`, leading to various oddities
    such as those observed in #14888. We now uniformly treat `(->)` as
    `ArrowT` in Template Haskell–world by checking for any tycon that
    has the same name as `(->)`, and converting that to `ArrowT`.
    
    Test Plan: make test TEST=T14888
    
    Reviewers: goldfire, bgamari, simonpj
    
    Reviewed By: goldfire, simonpj
    
    Subscribers: simonpj, rwbarton, thomie, carter
    
    GHC Trac Issues: #14888
    
    Differential Revision: https://phabricator.haskell.org/D4466


>---------------------------------------------------------------

6ee831f279c91888ee5815f8eee473bcd6fd25c6
 compiler/deSugar/DsMeta.hs       |  1 +
 compiler/typecheck/TcSplice.hs   |  1 +
 testsuite/tests/th/T14888.hs     | 18 ++++++++++++++++++
 testsuite/tests/th/T14888.stderr | 11 +++++++++++
 testsuite/tests/th/all.T         |  2 ++
 5 files changed, 33 insertions(+)

diff --git a/compiler/deSugar/DsMeta.hs b/compiler/deSugar/DsMeta.hs
index db25c55..5029f9d 100644
--- a/compiler/deSugar/DsMeta.hs
+++ b/compiler/deSugar/DsMeta.hs
@@ -994,6 +994,7 @@ repTy ty@(HsQualTy {})   = repForall ty
 repTy (HsTyVar _ (L _ n))
   | isLiftedTypeKindTyConName n       = repTStar
   | n `hasKey` constraintKindTyConKey = repTConstraint
+  | n `hasKey` funTyConKey            = repArrowTyCon
   | isTvOcc occ   = do tv1 <- lookupOcc n
                        repTvar tv1
   | isDataOcc occ = do tc1 <- lookupOcc n
diff --git a/compiler/typecheck/TcSplice.hs b/compiler/typecheck/TcSplice.hs
index 45e18e6..00591d1 100644
--- a/compiler/typecheck/TcSplice.hs
+++ b/compiler/typecheck/TcSplice.hs
@@ -1881,6 +1881,7 @@ reify_tc_app tc tys
          | isTupleTyCon tc                = if isPromotedDataCon tc
                                             then TH.PromotedTupleT arity
                                             else TH.TupleT arity
+         | tc `hasKey` funTyConKey        = TH.ArrowT
          | tc `hasKey` listTyConKey       = TH.ListT
          | tc `hasKey` nilDataConKey      = TH.PromotedNilT
          | tc `hasKey` consDataConKey     = TH.PromotedConsT
diff --git a/testsuite/tests/th/T14888.hs b/testsuite/tests/th/T14888.hs
new file mode 100644
index 0000000..e2bcec6
--- /dev/null
+++ b/testsuite/tests/th/T14888.hs
@@ -0,0 +1,18 @@
+{-# LANGUAGE TemplateHaskell #-}
+module T14888 where
+
+import Language.Haskell.TH
+
+foo :: $([t| (->) Bool Bool |])
+foo x = x
+
+class Functor' f where
+  fmap' :: (a -> b) -> f a -> f b
+
+instance Functor' ((->) r) where
+  fmap' = (.)
+
+$(return [])
+
+functor'Instances :: String
+functor'Instances = $(reify ''Functor' >>= stringE . pprint)
diff --git a/testsuite/tests/th/T14888.stderr b/testsuite/tests/th/T14888.stderr
new file mode 100644
index 0000000..963937f
--- /dev/null
+++ b/testsuite/tests/th/T14888.stderr
@@ -0,0 +1,11 @@
+T14888.hs:6:10-30: Splicing type
+    [t| (->) Bool Bool |] ======> Bool -> Bool
+T14888.hs:15:3-11: Splicing declarations return [] ======>
+T14888.hs:18:23-59: Splicing expression
+    reify ''Functor' >>= stringE . pprint
+  ======>
+    "class T14888.Functor' (f_0 :: * -> *)
+    where T14888.fmap' :: forall (f_0 :: * ->
+                                         *) . T14888.Functor' f_0 =>
+                          forall (a_1 :: *) (b_2 :: *) . (a_1 -> b_2) -> f_0 a_1 -> f_0 b_2
+instance T14888.Functor' ((->) r_3 :: * -> *)"
diff --git a/testsuite/tests/th/all.T b/testsuite/tests/th/all.T
index 47e8a9c..e9f2838 100644
--- a/testsuite/tests/th/all.T
+++ b/testsuite/tests/th/all.T
@@ -403,3 +403,5 @@ test('T14838', [], multimod_compile,
      ['T14838.hs', '-v0 -Wincomplete-patterns ' + config.ghc_th_way_flags])
 test('T14817', normal, compile, ['-v0 -ddump-splices -dsuppress-uniques'])
 test('T14843', normal, compile, ['-v0'])
+test('T14888', normal, compile,
+    ['-v0 -ddump-splices -dsuppress-uniques ' + config.ghc_th_way_flags])


From git at git.haskell.org  Mon Mar  5 14:45:41 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon,  5 Mar 2018 14:45:41 +0000 (UTC)
Subject: [commit: ghc] master: Simplify rnLHsInstType (1c062b7)
Message-ID: <20180305144541.CC3E43A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/1c062b794bf71a329f65813ce7b72fe2bd3935f0/ghc

>---------------------------------------------------------------

commit 1c062b794bf71a329f65813ce7b72fe2bd3935f0
Author: Simon Peyton Jones <simonpj at microsoft.com>
Date:   Mon Mar 5 14:40:37 2018 +0000

    Simplify rnLHsInstType
    
    This patch is preparatory for the main fix for Trac #13324
    
    Here, we simplify rnLHsInstType so that it does not try
    to figure out the class name.  This turns out to have a good
    (rather than bad) effect on error messages, and it prepares
    the way for the main event.
    
    Plus, less code!


>---------------------------------------------------------------

1c062b794bf71a329f65813ce7b72fe2bd3935f0
 compiler/rename/RnTypes.hs                              | 17 +++--------------
 testsuite/tests/parser/should_fail/T3811c.stderr        |  5 ++++-
 .../should_fail/WildcardInInstanceHead.stderr           |  2 +-
 .../should_fail/WildcardInStandaloneDeriving.stderr     |  2 --
 testsuite/tests/rename/should_fail/T5513.stderr         |  4 +++-
 testsuite/tests/rename/should_fail/T5951.stderr         | 15 ++++++++++++++-
 6 files changed, 25 insertions(+), 20 deletions(-)

diff --git a/compiler/rename/RnTypes.hs b/compiler/rename/RnTypes.hs
index 2305a04..b2dafb2 100644
--- a/compiler/rename/RnTypes.hs
+++ b/compiler/rename/RnTypes.hs
@@ -326,20 +326,8 @@ rnImplicitBndrs bind_free_tvs doc
 rnLHsInstType :: SDoc -> LHsSigType GhcPs -> RnM (LHsSigType GhcRn, FreeVars)
 -- Rename the type in an instance or standalone deriving decl
 -- The 'doc_str' is "an instance declaration" or "a VECTORISE pragma"
-rnLHsInstType doc_str inst_ty
-  | Just cls <- getLHsInstDeclClass_maybe inst_ty
-  , isTcOcc (rdrNameOcc (unLoc cls))
-         -- The guards check that the instance type looks like
-         --   blah => C ty1 .. tyn
-  = do { let full_doc = doc_str <+> text "for" <+> quotes (ppr cls)
-       ; rnHsSigType (GenericCtx full_doc) inst_ty }
-
-  | otherwise  -- The instance is malformed, but we'd still like
-               -- to make progress rather than failing outright, so
-               -- we report more errors.  So we rename it anyway.
-  = do { addErrAt (getLoc (hsSigType inst_ty)) $
-         text "Malformed instance:" <+> ppr inst_ty
-       ; rnHsSigType (GenericCtx doc_str) inst_ty }
+-- Do not try to decompose the inst_ty in case it is malformed
+rnLHsInstType doc inst_ty = rnHsSigType (GenericCtx doc) inst_ty
 
 mk_implicit_bndrs :: [Name]  -- implicitly bound
                   -> a           -- payload
@@ -351,6 +339,7 @@ mk_implicit_bndrs vars body fvs
          , hsib_closed = nameSetAll (not . isTyVarName) (vars `delFVs` fvs) }
 
 
+
 {- ******************************************************
 *                                                       *
            LHsType and HsType
diff --git a/testsuite/tests/parser/should_fail/T3811c.stderr b/testsuite/tests/parser/should_fail/T3811c.stderr
index 4a37116..dd21918 100644
--- a/testsuite/tests/parser/should_fail/T3811c.stderr
+++ b/testsuite/tests/parser/should_fail/T3811c.stderr
@@ -1,2 +1,5 @@
 
-T3811c.hs:6:10: Malformed instance: !Show D
+T3811c.hs:6:10: error:
+    • Unexpected strictness annotation: !Show
+      strictness annotation cannot appear nested inside a type
+    • In the instance declaration for ‘!Show D’
diff --git a/testsuite/tests/partial-sigs/should_fail/WildcardInInstanceHead.stderr b/testsuite/tests/partial-sigs/should_fail/WildcardInInstanceHead.stderr
index 9090475..367e10a 100644
--- a/testsuite/tests/partial-sigs/should_fail/WildcardInInstanceHead.stderr
+++ b/testsuite/tests/partial-sigs/should_fail/WildcardInInstanceHead.stderr
@@ -1,4 +1,4 @@
 
 WildcardInInstanceHead.hs:7:14: error:
     Wildcard ‘_’ not allowed
-      in an instance declaration for ‘Foo’
+      in an instance declaration
diff --git a/testsuite/tests/partial-sigs/should_fail/WildcardInStandaloneDeriving.stderr b/testsuite/tests/partial-sigs/should_fail/WildcardInStandaloneDeriving.stderr
index 8e98910..0609021 100644
--- a/testsuite/tests/partial-sigs/should_fail/WildcardInStandaloneDeriving.stderr
+++ b/testsuite/tests/partial-sigs/should_fail/WildcardInStandaloneDeriving.stderr
@@ -1,6 +1,4 @@
 
-WildcardInStandaloneDeriving.hs:4:19: error: Malformed instance: _
-
 WildcardInStandaloneDeriving.hs:4:19: error:
     Wildcard ‘_’ not allowed
       in a deriving declaration
diff --git a/testsuite/tests/rename/should_fail/T5513.stderr b/testsuite/tests/rename/should_fail/T5513.stderr
index 063f348..7e26622 100644
--- a/testsuite/tests/rename/should_fail/T5513.stderr
+++ b/testsuite/tests/rename/should_fail/T5513.stderr
@@ -1,2 +1,4 @@
 
-T5513.hs:4:19: Malformed instance: lowercase_name a
+T5513.hs:4:19: error:
+    • Instance head is not headed by a class
+    • In the stand-alone deriving instance for ‘lowercase_name a’
diff --git a/testsuite/tests/rename/should_fail/T5951.stderr b/testsuite/tests/rename/should_fail/T5951.stderr
index af0ee9d..8fda353 100644
--- a/testsuite/tests/rename/should_fail/T5951.stderr
+++ b/testsuite/tests/rename/should_fail/T5951.stderr
@@ -1,2 +1,15 @@
 
-T5951.hs:8:8: Malformed instance: A => B => C
+T5951.hs:8:8: error:
+    • Expecting one more argument to ‘A’
+      Expected a constraint, but ‘A’ has kind ‘* -> Constraint’
+    • In the instance declaration for ‘B => C’
+
+T5951.hs:9:8: error:
+    • Expecting one more argument to ‘B’
+      Expected a constraint, but ‘B’ has kind ‘* -> Constraint’
+    • In the instance declaration for ‘B => C’
+
+T5951.hs:10:8: error:
+    • Expecting one more argument to ‘C’
+      Expected a constraint, but ‘C’ has kind ‘* -> Constraint’
+    • In the instance declaration for ‘B => C’


From git at git.haskell.org  Mon Mar  5 14:51:53 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon,  5 Mar 2018 14:51:53 +0000 (UTC)
Subject: [commit: ghc] branch 'wip/T13324' created
Message-ID: <20180305145153.851433A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

New branch : wip/T13324
Referencing: 7d491ae76b32a78c1ea09a324f67937adceecfc2

From git at git.haskell.org  Mon Mar  5 14:51:56 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon,  5 Mar 2018 14:51:56 +0000 (UTC)
Subject: [commit: ghc] wip/T13324: Use LHsSigWcType in DerivDecl (7d491ae)
Message-ID: <20180305145156.81C803A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/T13324
Link       : http://ghc.haskell.org/trac/ghc/changeset/7d491ae76b32a78c1ea09a324f67937adceecfc2/ghc

>---------------------------------------------------------------

commit 7d491ae76b32a78c1ea09a324f67937adceecfc2
Author: Simon Peyton Jones <simonpj at microsoft.com>
Date:   Mon Mar 5 14:50:00 2018 +0000

    Use LHsSigWcType in DerivDecl
    
    This prepares the way for the fix for Trac #13324, by
    using LHsSigWcType for the instance type in DerivDecl,
    but nowhere else.
    
    See comments on Phab:D4383


>---------------------------------------------------------------

7d491ae76b32a78c1ea09a324f67937adceecfc2
 compiler/deSugar/DsMeta.hs    | 2 +-
 compiler/hsSyn/Convert.hs     | 2 +-
 compiler/hsSyn/HsDecls.hs     | 2 +-
 compiler/parser/Parser.y      | 7 ++++---
 compiler/rename/RnSource.hs   | 9 ++++++---
 compiler/rename/RnTypes.hs    | 7 -------
 compiler/typecheck/TcDeriv.hs | 7 +++++--
 7 files changed, 18 insertions(+), 18 deletions(-)

diff --git a/compiler/deSugar/DsMeta.hs b/compiler/deSugar/DsMeta.hs
index 5029f9d..e1eaae1 100644
--- a/compiler/deSugar/DsMeta.hs
+++ b/compiler/deSugar/DsMeta.hs
@@ -488,7 +488,7 @@ repStandaloneDerivD (L loc (DerivDecl { deriv_strategy = strat
                    ; repDeriv strat' cxt' inst_ty' }
        ; return (loc, dec) }
   where
-    (tvs, cxt, inst_ty) = splitLHsInstDeclTy ty
+    (tvs, cxt, inst_ty) = splitLHsInstDeclTy (hswc_body ty)
 
 repTyFamInstD :: TyFamInstDecl GhcRn -> DsM (Core TH.DecQ)
 repTyFamInstD decl@(TyFamInstDecl { tfid_eqn = eqn })
diff --git a/compiler/hsSyn/Convert.hs b/compiler/hsSyn/Convert.hs
index 531f146..6c2e58c 100644
--- a/compiler/hsSyn/Convert.hs
+++ b/compiler/hsSyn/Convert.hs
@@ -351,7 +351,7 @@ cvtDec (TH.StandaloneDerivD ds cxt ty)
        ; let inst_ty' = mkHsQualTy cxt loc cxt' $ L loc ty'
        ; returnJustL $ DerivD $
          DerivDecl { deriv_strategy = fmap (L loc . cvtDerivStrategy) ds
-                   , deriv_type = mkLHsSigType inst_ty'
+                   , deriv_type = mkLHsSigWcType inst_ty'
                    , deriv_overlap_mode = Nothing } }
 
 cvtDec (TH.DefaultSigD nm typ)
diff --git a/compiler/hsSyn/HsDecls.hs b/compiler/hsSyn/HsDecls.hs
index 475e31e..660fc2a 100644
--- a/compiler/hsSyn/HsDecls.hs
+++ b/compiler/hsSyn/HsDecls.hs
@@ -1659,7 +1659,7 @@ type LDerivDecl pass = Located (DerivDecl pass)
 
 -- | Deriving Declaration
 data DerivDecl pass = DerivDecl
-        { deriv_type         :: LHsSigType pass
+        { deriv_type         :: LHsSigWcType pass
         , deriv_strategy     :: Maybe (Located DerivStrategy)
         , deriv_overlap_mode :: Maybe (Located OverlapMode)
          -- ^ - 'ApiAnnotation.AnnKeywordId' : 'ApiAnnotation.AnnDeriving',
diff --git a/compiler/parser/Parser.y b/compiler/parser/Parser.y
index 898ed3c..bdb5e6b 100644
--- a/compiler/parser/Parser.y
+++ b/compiler/parser/Parser.y
@@ -1373,10 +1373,11 @@ capi_ctype : '{-# CTYPE' STRING STRING '#-}'
 
 -- Glasgow extension: stand-alone deriving declarations
 stand_alone_deriving :: { LDerivDecl GhcPs }
-  : 'deriving' deriv_strategy 'instance' overlap_pragma inst_type
+  : 'deriving' deriv_strategy 'instance' overlap_pragma sigtype
                 {% do { let { err = text "in the stand-alone deriving instance"
-                                    <> colon <+> quotes (ppr $5) }
-                      ; ams (sLL $1 (hsSigType $>) (DerivDecl $5 $2 $4))
+                                    <> colon <+> quotes (ppr $5)
+                            ; inst_ty = mkLHsSigWcType $5 }
+                      ; ams (sLL $1 $> (DerivDecl inst_ty $2 $4))
                             [mj AnnDeriving $1, mj AnnInstance $3] } }
 
 -----------------------------------------------------------------------------
diff --git a/compiler/rename/RnSource.hs b/compiler/rename/RnSource.hs
index 447871a..53feacb 100644
--- a/compiler/rename/RnSource.hs
+++ b/compiler/rename/RnSource.hs
@@ -634,7 +634,8 @@ rnClsInstDecl (ClsInstDecl { cid_poly_ty = inst_ty, cid_binds = mbinds
                            , cid_sigs = uprags, cid_tyfam_insts = ats
                            , cid_overlap_mode = oflag
                            , cid_datafam_insts = adts })
-  = do { (inst_ty', inst_fvs) <- rnLHsInstType (text "an instance declaration") inst_ty
+  = do { let ctxt = GenericCtx (text "an instance declaration")
+       ; (inst_ty', inst_fvs) <- rnHsSigType ctxt inst_ty
        ; let (ktv_names, _, head_ty') = splitLHsInstDeclTy inst_ty'
        ; let cls = case hsTyGetAppHead_maybe head_ty' of
                      Nothing -> mkUnboundName (mkTcOccFS (fsLit "<class>"))
@@ -945,7 +946,8 @@ rnSrcDerivDecl (DerivDecl ty deriv_strat overlap)
        ; unless standalone_deriv_ok (addErr standaloneDerivErr)
        ; failIfTc (isJust deriv_strat && not deriv_strats_ok) $
            illegalDerivStrategyErr $ fmap unLoc deriv_strat
-       ; (ty', fvs) <- rnLHsInstType (text "a deriving declaration") ty
+       ; let ctxt = GenericCtx (text "a deriving declaration")
+       ; (ty', fvs) <- rnHsSigWcType ctxt ty
        ; return (DerivDecl ty' deriv_strat overlap, fvs) }
 
 standaloneDerivErr :: SDoc
@@ -1124,7 +1126,8 @@ rnHsVectDecl (HsVectClassIn s cls)
 rnHsVectDecl (HsVectClassOut _)
   = panic "RnSource.rnHsVectDecl: Unexpected 'HsVectClassOut'"
 rnHsVectDecl (HsVectInstIn instTy)
-  = do { (instTy', fvs) <- rnLHsInstType (text "a VECTORISE pragma") instTy
+  = do { let ctxt = GenericCtx (text "a VECTORISE pragma")
+       ; (instTy', fvs) <- rnHsSigType ctxt instTy
        ; return (HsVectInstIn instTy', fvs)
        }
 rnHsVectDecl (HsVectInstOut _)
diff --git a/compiler/rename/RnTypes.hs b/compiler/rename/RnTypes.hs
index b2dafb2..791881b 100644
--- a/compiler/rename/RnTypes.hs
+++ b/compiler/rename/RnTypes.hs
@@ -13,7 +13,6 @@ module RnTypes (
         rnHsKind, rnLHsKind,
         rnHsSigType, rnHsWcType,
         rnHsSigWcType, rnHsSigWcTypeScoped,
-        rnLHsInstType,
         newTyVarNameRn, collectAnonWildCards,
         rnConDeclFields,
         rnLTyVar,
@@ -323,12 +322,6 @@ rnImplicitBndrs bind_free_tvs doc
        ; bindLocalNamesFV vars $
          thing_inside vars }
 
-rnLHsInstType :: SDoc -> LHsSigType GhcPs -> RnM (LHsSigType GhcRn, FreeVars)
--- Rename the type in an instance or standalone deriving decl
--- The 'doc_str' is "an instance declaration" or "a VECTORISE pragma"
--- Do not try to decompose the inst_ty in case it is malformed
-rnLHsInstType doc inst_ty = rnHsSigType (GenericCtx doc) inst_ty
-
 mk_implicit_bndrs :: [Name]  -- implicitly bound
                   -> a           -- payload
                   -> FreeVars    -- FreeVars of payload
diff --git a/compiler/typecheck/TcDeriv.hs b/compiler/typecheck/TcDeriv.hs
index 294b42c..35d95b9 100644
--- a/compiler/typecheck/TcDeriv.hs
+++ b/compiler/typecheck/TcDeriv.hs
@@ -607,13 +607,16 @@ deriveStandalone :: LDerivDecl GhcRn -> TcM (Maybe EarlyDerivSpec)
 -- This returns a Maybe because the user might try to derive Typeable, which is
 -- a no-op nowadays.
 deriveStandalone (L loc (DerivDecl deriv_ty deriv_strat' overlap_mode))
+  | let deriv_ty_no_wc = dropWildCards deriv_ty
+            -- dropWildCards; just awaiting the rest of Phab:D4383
   = setSrcSpan loc                   $
-    addErrCtxt (standaloneCtxt deriv_ty)  $
+    addErrCtxt (standaloneCtxt deriv_ty_no_wc)  $
     do { traceTc "Standalone deriving decl for" (ppr deriv_ty)
        ; let deriv_strat = fmap unLoc deriv_strat'
        ; traceTc "Deriving strategy (standalone deriving)" $
            vcat [ppr deriv_strat, ppr deriv_ty]
-       ; (tvs, theta, cls, inst_tys) <- tcHsClsInstType TcType.InstDeclCtxt deriv_ty
+       ; (tvs, theta, cls, inst_tys) <- tcHsClsInstType TcType.InstDeclCtxt
+                                                        deriv_ty_no_wc
        ; traceTc "Standalone deriving;" $ vcat
               [ text "tvs:" <+> ppr tvs
               , text "theta:" <+> ppr theta


From git at git.haskell.org  Mon Mar  5 20:34:13 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon,  5 Mar 2018 20:34:13 +0000 (UTC)
Subject: [commit: ghc] master: Fixup include of gmp/config.mk to use new
 location (df7ac37)
Message-ID: <20180305203413.4B6993A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/df7ac37d43bdbabbde9b09344f9425e8e5a879ff/ghc

>---------------------------------------------------------------

commit df7ac37d43bdbabbde9b09344f9425e8e5a879ff
Author: Herbert Valerio Riedel <hvr at gnu.org>
Date:   Mon Mar 5 21:13:28 2018 +0100

    Fixup include of gmp/config.mk to use new location
    
    This wasn't spotted rightaway in
    8f0b2f5eadf0fcb47c581907205a9db686214a69
    because the include-site deliberately ignored include-errors as
    a Hack with the justification below:
    
    > Hack. The file gmp/config.mk doesn't exist yet after running ./configure in
    > the toplevel (ghc) directory. To let some toplevel make commands such as
    > sdist go through, right after ./configure, don't consider this an error.
    
    This may have contributed to #14891.


>---------------------------------------------------------------

df7ac37d43bdbabbde9b09344f9425e8e5a879ff
 libraries/integer-gmp/gmp/ghc.mk | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libraries/integer-gmp/gmp/ghc.mk b/libraries/integer-gmp/gmp/ghc.mk
index 794942c..556a271 100644
--- a/libraries/integer-gmp/gmp/ghc.mk
+++ b/libraries/integer-gmp/gmp/ghc.mk
@@ -56,7 +56,7 @@ ifneq "$(CLEANING)" "YES"
 # Hack. The file gmp/config.mk doesn't exist yet after running ./configure in
 # the toplevel (ghc) directory. To let some toplevel make commands such as
 # sdist go through, right after ./configure, don't consider this an error.
--include libraries/integer-gmp/gmp/config.mk
+-include libraries/integer-gmp/dist-install/build/gmp/config.mk
 endif
 
 gmp_CC_OPTS += $(addprefix -I,$(GMP_INCLUDE_DIRS))


From git at git.haskell.org  Tue Mar  6 01:26:15 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue,  6 Mar 2018 01:26:15 +0000 (UTC)
Subject: [commit: ghc] master: `--via-asm` only for windows targets (f6cf400)
Message-ID: <20180306012615.30A3E3A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/f6cf4001574e789865d25f89b362a04ef1ca3df4/ghc

>---------------------------------------------------------------

commit f6cf4001574e789865d25f89b362a04ef1ca3df4
Author: Moritz Angermann <moritz.angermann at gmail.com>
Date:   Mon Mar 5 17:18:25 2018 +0800

    `--via-asm` only for windows targets
    
    Reviewers: trofi, bgamari
    
    Reviewed By: trofi, bgamari
    
    Subscribers: rwbarton, thomie, carter
    
    Differential Revision: https://phabricator.haskell.org/D4467


>---------------------------------------------------------------

f6cf4001574e789865d25f89b362a04ef1ca3df4
 mk/config.mk.in | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/mk/config.mk.in b/mk/config.mk.in
index 26b07f3..92830fa 100644
--- a/mk/config.mk.in
+++ b/mk/config.mk.in
@@ -649,12 +649,16 @@ $(eval $(call set_stage_HSC2HS_OPTS,0))
 $(eval $(call set_stage_HSC2HS_OPTS,1))
 $(eval $(call set_stage_HSC2HS_OPTS,2))
 ifeq "$(CrossCompiling)" "YES"
+SRC_HSC2HS_OPTS_STAGE1 += --cross-compile
+SRC_HSC2HS_OPTS_STAGE2 += --cross-compile
+ifeq "$(Windows_Target)" "YES"
 # We'll assume we compile with gcc or clang, and both support `-S` and can as such use the
 # --via-asm pass, which should be faster and is required for cross compiling to windows, as
 # the c compiler complains about non-constant expressions even though they are constant and
 # end up as constants in the assembly.
-SRC_HSC2HS_OPTS_STAGE1 += --cross-compile --via-asm
-SRC_HSC2HS_OPTS_STAGE2 += --cross-compile --via-asm
+SRC_HSC2HS_OPTS_STAGE1 += --via-asm
+SRC_HSC2HS_OPTS_STAGE2 += --via-asm
+endif
 endif
 SRC_HSC2HS_OPTS_STAGE0 += --cflag=-D$(HostArch_CPP)_HOST_ARCH --cflag=-D$(HostOS_CPP)_HOST_OS
 SRC_HSC2HS_OPTS_STAGE1 += --cflag=-D$(TargetArch_CPP)_HOST_ARCH --cflag=-D$(TargetOS_CPP)_HOST_OS


From git at git.haskell.org  Tue Mar  6 01:28:07 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue,  6 Mar 2018 01:28:07 +0000 (UTC)
Subject: [commit: ghc] wip/angerman/win32-cross-2: temp fix Makefile (7ca07cd)
Message-ID: <20180306012807.C7F973A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/angerman/win32-cross-2
Link       : http://ghc.haskell.org/trac/ghc/changeset/7ca07cdd2ab553989c815a8674fa337fff216ea4/ghc

>---------------------------------------------------------------

commit 7ca07cdd2ab553989c815a8674fa337fff216ea4
Author: Moritz Angermann <moritz.angermann at gmail.com>
Date:   Thu Feb 15 12:29:14 2018 +0800

    temp fix Makefile


>---------------------------------------------------------------

7ca07cdd2ab553989c815a8674fa337fff216ea4
 utils/iserv/Makefile | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/utils/iserv/Makefile b/utils/iserv/Makefile
index f160978..3619858 100644
--- a/utils/iserv/Makefile
+++ b/utils/iserv/Makefile
@@ -10,6 +10,6 @@
 #
 # -----------------------------------------------------------------------------
 
-dir = iserv
-TOP = ..
+dir = utils/iserv
+TOP = ../..
 include $(TOP)/mk/sub-makefile.mk


From git at git.haskell.org  Tue Mar  6 01:28:10 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue,  6 Mar 2018 01:28:10 +0000 (UTC)
Subject: [commit: ghc] wip/angerman/win32-cross-2: adds .gitignore (84cc122)
Message-ID: <20180306012810.966063A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/angerman/win32-cross-2
Link       : http://ghc.haskell.org/trac/ghc/changeset/84cc1225450b631b2f0b6e574353d98c8efd7967/ghc

>---------------------------------------------------------------

commit 84cc1225450b631b2f0b6e574353d98c8efd7967
Author: Moritz Angermann <moritz.angermann at gmail.com>
Date:   Thu Feb 15 13:54:55 2018 +0800

    adds .gitignore


>---------------------------------------------------------------

84cc1225450b631b2f0b6e574353d98c8efd7967
 .gitignore | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/.gitignore b/.gitignore
index 460cb68..4d815d7 100644
--- a/.gitignore
+++ b/.gitignore
@@ -81,8 +81,7 @@ _darcs/
 /ghc/stage1/
 /ghc/stage2/
 /ghc/stage3/
-/iserv/stage2*/
-/iserv/dist/
+/utils/iserv/stage2*/
 
 # -----------------------------------------------------------------------------
 # specific generated files


From git at git.haskell.org  Tue Mar  6 01:28:14 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue,  6 Mar 2018 01:28:14 +0000 (UTC)
Subject: [commit: ghc] wip/angerman/win32-cross-2: Move `iserv` into `utils`
 and change package name from `iserv-bin` to `iserv` (8024b87)
Message-ID: <20180306012814.BE3E33A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/angerman/win32-cross-2
Link       : http://ghc.haskell.org/trac/ghc/changeset/8024b87f7f2b769d4eaf01c872e96ea973bc46d0/ghc

>---------------------------------------------------------------

commit 8024b87f7f2b769d4eaf01c872e96ea973bc46d0
Author: Moritz Angermann <moritz.angermann at gmail.com>
Date:   Sat Nov 25 15:10:52 2017 +0800

    Move `iserv` into `utils` and change package name from `iserv-bin` to `iserv`
    
    This is done for consistency. We usually call the package file the same name the
    folder has.  The move into `utils` is done so that we can move the library into
    `libraries/iserv` and the proxy into `utils/iserv-proxy` and then break the
    `iserv.cabal` apart.  This will make building the cross compiler with TH
    simpler, because we can build the library and proxy as separate packages.
    
    # Conflicts:
    #	utils/iserv-proxy/iserv-proxy.cabal


>---------------------------------------------------------------

8024b87f7f2b769d4eaf01c872e96ea973bc46d0
 ghc.mk                                             |  13 +--
 {iserv => libraries/libiserv}/Makefile             |   0
 {iserv => libraries/libiserv}/cbits/iservmain.c    |   0
 libraries/libiserv/ghc.mk                          |   5 +
 libraries/libiserv/libiserv.cabal                  |  39 +++++++
 {iserv => libraries/libiserv}/proxy-src/Remote.hs  |   0
 {iserv => libraries/libiserv}/src/GHCi/Utils.hsc   |   0
 {iserv => libraries/libiserv}/src/Lib.hs           |   0
 {iserv => libraries/libiserv}/src/Main.hs          |   0
 .../libiserv}/src/Remote/Message.hs                |   0
 {iserv => libraries/libiserv}/src/Remote/Slave.hs  |   0
 {iserv => utils/iserv-proxy}/Makefile              |   0
 utils/iserv-proxy/ghc.mk                           | 113 +++++++++++++++++++++
 .../iserv-proxy/iserv-proxy.cabal                  |  72 +------------
 .../Remote.hs => utils/iserv-proxy/src/Main.hs     |   0
 {iserv => utils/iserv}/Makefile                    |   0
 {iserv => utils/iserv}/cbits/iservmain.c           |   0
 {iserv => utils/iserv}/ghc.mk                      |  66 ++++++------
 utils/iserv/iserv.cabal                            |  44 ++++++++
 {iserv => utils/iserv}/src/Main.hs                 |   0
 20 files changed, 246 insertions(+), 106 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc 8024b87f7f2b769d4eaf01c872e96ea973bc46d0

From git at git.haskell.org  Tue Mar  6 01:28:17 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue,  6 Mar 2018 01:28:17 +0000 (UTC)
Subject: [commit: ghc] wip/angerman/win32-cross-2: Move `iserv` into `utils`
 and change package name from `iserv-bin` to `iserv` (7427d69)
Message-ID: <20180306012817.8BEB73A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/angerman/win32-cross-2
Link       : http://ghc.haskell.org/trac/ghc/changeset/7427d69403c199151f1687b851e8f006695595c3/ghc

>---------------------------------------------------------------

commit 7427d69403c199151f1687b851e8f006695595c3
Author: Moritz Angermann <moritz.angermann at gmail.com>
Date:   Thu Feb 22 16:53:35 2018 +0800

    Move `iserv` into `utils` and change package name from `iserv-bin` to `iserv`
    
    Summary:
    This is done for consistency. We usually call the package file the same name the
    folder has.  The move into `utils` is done so that we can move the library into
    `libraries/iserv` and the proxy into `utils/iserv-proxy` and then break the
    `iserv.cabal` apart.  This will make building the cross compiler with TH
    simpler, because we can build the library and proxy as separate packages.
    
    Test Plan: ./validate
    
    Reviewers: bgamari, goldfire, erikd
    
    Subscribers: rwbarton, thomie, carter
    
    Differential Revision: https://phabricator.haskell.org/D4436


>---------------------------------------------------------------

7427d69403c199151f1687b851e8f006695595c3
 libraries/libiserv/src/Main.hs | 63 ------------------------------------------
 1 file changed, 63 deletions(-)

diff --git a/libraries/libiserv/src/Main.hs b/libraries/libiserv/src/Main.hs
deleted file mode 100644
index 858cee8..0000000
--- a/libraries/libiserv/src/Main.hs
+++ /dev/null
@@ -1,63 +0,0 @@
-{-# LANGUAGE CPP, GADTs #-}
-
--- |
--- The Remote GHCi server.
---
--- For details on Remote GHCi, see Note [Remote GHCi] in
--- compiler/ghci/GHCi.hs.
---
-module Main (main) where
-
-import Lib (serv)
-
-import GHCi.Message
-import GHCi.Signals
-import GHCi.Utils
-
-import Control.Exception
-import Control.Monad
-import Data.IORef
-import System.Environment
-import System.Exit
-import Text.Printf
-
-dieWithUsage :: IO a
-dieWithUsage = do
-    prog <- getProgName
-    die $ prog ++ ": " ++ msg
-  where
-#ifdef WINDOWS
-    msg = "usage: iserv <write-handle> <read-handle> [-v]"
-#else
-    msg = "usage: iserv <write-fd> <read-fd> [-v]"
-#endif
-
-main :: IO ()
-main = do
-  args <- getArgs
-  (wfd1, rfd2, rest) <-
-      case args of
-        arg0:arg1:rest -> do
-            let wfd1 = read arg0
-                rfd2 = read arg1
-            return (wfd1, rfd2, rest)
-        _ -> dieWithUsage
-
-  verbose <- case rest of
-    ["-v"] -> return True
-    []     -> return False
-    _      -> dieWithUsage
-  when verbose $
-    printf "GHC iserv starting (in: %d; out: %d)\n"
-      (fromIntegral rfd2 :: Int) (fromIntegral wfd1 :: Int)
-  inh  <- getGhcHandle rfd2
-  outh <- getGhcHandle wfd1
-  installSignalHandlers
-  lo_ref <- newIORef Nothing
-  let pipe = Pipe{pipeRead = inh, pipeWrite = outh, pipeLeftovers = lo_ref}
-  uninterruptibleMask $ serv verbose hook pipe
-
-  where hook = return -- empty hook
-    -- we cannot allow any async exceptions while communicating, because
-    -- we will lose sync in the protocol, hence uninterruptibleMask.
-


From git at git.haskell.org  Tue Mar  6 01:28:20 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue,  6 Mar 2018 01:28:20 +0000 (UTC)
Subject: [commit: ghc] wip/angerman/win32-cross-2's head updated: Move `iserv`
 into `utils` and change package name from `iserv-bin` to `iserv` (7427d69)
Message-ID: <20180306012820.8279C3A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

Branch 'wip/angerman/win32-cross-2' now includes:

     e7653bc Wombling around in Trac #14808
     3d25203 Respect Note [The tcType invariant]
     6ee831f Fix #14888 by adding more special cases for ArrowT
     1c062b7 Simplify rnLHsInstType
     df7ac37 Fixup include of gmp/config.mk to use new location
     f6cf400 `--via-asm` only for windows targets
     8024b87 Move `iserv` into `utils` and change package name from `iserv-bin` to `iserv`
     7ca07cd temp fix Makefile
     84cc122 adds .gitignore
     7427d69 Move `iserv` into `utils` and change package name from `iserv-bin` to `iserv`

From git at git.haskell.org  Tue Mar  6 03:20:43 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue,  6 Mar 2018 03:20:43 +0000 (UTC)
Subject: [commit: ghc] wip/angerman/win32-cross-2: add CCX=$(CXX) to
 integer-gmp (1dfd7aa)
Message-ID: <20180306032043.3B9123A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/angerman/win32-cross-2
Link       : http://ghc.haskell.org/trac/ghc/changeset/1dfd7aa2cb06adccc9180463807e62260d66c90e/ghc

>---------------------------------------------------------------

commit 1dfd7aa2cb06adccc9180463807e62260d66c90e
Author: Moritz Angermann <moritz.angermann at gmail.com>
Date:   Tue Mar 6 11:20:22 2018 +0800

    add CCX=$(CXX) to integer-gmp


>---------------------------------------------------------------

1dfd7aa2cb06adccc9180463807e62260d66c90e
 libraries/integer-gmp/gmp/ghc.mk | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libraries/integer-gmp/gmp/ghc.mk b/libraries/integer-gmp/gmp/ghc.mk
index 556a271..f18e27d 100644
--- a/libraries/integer-gmp/gmp/ghc.mk
+++ b/libraries/integer-gmp/gmp/ghc.mk
@@ -131,7 +131,7 @@ libraries/integer-gmp/gmp/libgmp.a libraries/integer-gmp/gmp/gmp.h:
 	#       `./configure`, not `HOSTPLATFORM`: the 'host' on which GMP will
 	#       run is the 'target' platform of the compiler we're building.
 	cd libraries/integer-gmp/gmp/gmpbuild; \
-	    CC=$(CCX) NM=$(NM) AR=$(AR_STAGE1) ./configure \
+	    CC=$(CCX) CXX=$(CCX) NM=$(NM) AR=$(AR_STAGE1) ./configure \
 	          --enable-shared=no \
 	          --host=$(TARGETPLATFORM) --build=$(BUILDPLATFORM)
 	$(MAKE) -C libraries/integer-gmp/gmp/gmpbuild MAKEFLAGS=


From git at git.haskell.org  Tue Mar  6 09:52:24 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue,  6 Mar 2018 09:52:24 +0000 (UTC)
Subject: [commit: ghc] master: add CCX=$(CXX) to integer-gmp (cf5bc96)
Message-ID: <20180306095224.E25553A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/cf5bc96e1b023275ec3c0399f3345ceebbc48df0/ghc

>---------------------------------------------------------------

commit cf5bc96e1b023275ec3c0399f3345ceebbc48df0
Author: Moritz Angermann <moritz.angermann at gmail.com>
Date:   Tue Mar 6 11:20:22 2018 +0800

    add CCX=$(CXX) to integer-gmp
    
    Summary:
    This came up when trying to build GHC HEAD with nix. We
    do not set CCX for integer-gmp when running ./configure. We do
    this however for libffi.
    
    The result is, that if CCX is not set, we default to the system
    one, of which there might be none (as in nixos's case).  This
    will not show on a debian+nix or similar setup, where the system
    `cxx` is still in place, and only shows up when the system tries
    hard to sandbox everything (even cxx) as nixOS does.
    
    We use `CXX`, which is set to either `clang` or `CC_STAGE1`, and
    also usedfor `CC`, similar to what we do for libffi.c
    
    Test Plan: ./validate
    
    Reviewers: bgamari, hvr
    
    Reviewed By: hvr
    
    Subscribers: rwbarton, thomie, carter
    
    Differential Revision: https://phabricator.haskell.org/D4473


>---------------------------------------------------------------

cf5bc96e1b023275ec3c0399f3345ceebbc48df0
 libraries/integer-gmp/gmp/ghc.mk | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libraries/integer-gmp/gmp/ghc.mk b/libraries/integer-gmp/gmp/ghc.mk
index 556a271..f18e27d 100644
--- a/libraries/integer-gmp/gmp/ghc.mk
+++ b/libraries/integer-gmp/gmp/ghc.mk
@@ -131,7 +131,7 @@ libraries/integer-gmp/gmp/libgmp.a libraries/integer-gmp/gmp/gmp.h:
 	#       `./configure`, not `HOSTPLATFORM`: the 'host' on which GMP will
 	#       run is the 'target' platform of the compiler we're building.
 	cd libraries/integer-gmp/gmp/gmpbuild; \
-	    CC=$(CCX) NM=$(NM) AR=$(AR_STAGE1) ./configure \
+	    CC=$(CCX) CXX=$(CCX) NM=$(NM) AR=$(AR_STAGE1) ./configure \
 	          --enable-shared=no \
 	          --host=$(TARGETPLATFORM) --build=$(BUILDPLATFORM)
 	$(MAKE) -C libraries/integer-gmp/gmp/gmpbuild MAKEFLAGS=


From git at git.haskell.org  Tue Mar  6 12:10:32 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue,  6 Mar 2018 12:10:32 +0000 (UTC)
Subject: [commit: ghc] master: Schedule.c: remove a redundant CPP guard
 (ee597e9)
Message-ID: <20180306121032.AD2A73A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/ee597e9ec78ceb1a9a208c16dbdeb0b67b4ba5ec/ghc

>---------------------------------------------------------------

commit ee597e9ec78ceb1a9a208c16dbdeb0b67b4ba5ec
Author: Ömer Sinan Ağacan <omeragacan at gmail.com>
Date:   Tue Mar 6 14:16:00 2018 +0300

    Schedule.c: remove a redundant CPP guard
    
    (the CPP guard is already wrapped with the same guard in line 1549)


>---------------------------------------------------------------

ee597e9ec78ceb1a9a208c16dbdeb0b67b4ba5ec
 rts/Schedule.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/rts/Schedule.c b/rts/Schedule.c
index b8306df..885e737 100644
--- a/rts/Schedule.c
+++ b/rts/Schedule.c
@@ -1738,10 +1738,8 @@ scheduleDoGC (Capability **pcap, Task *task USED_IF_THREADS,
         // they have stopped mutating and are standing by for GC.
         waitForGcThreads(cap, idle_cap);
 
-#if defined(THREADED_RTS)
         // Stable point where we can do a global check on our spark counters
         ASSERT(checkSparkCountInvariant());
-#endif
     }
 
 #endif


From git at git.haskell.org  Tue Mar  6 13:57:11 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue,  6 Mar 2018 13:57:11 +0000 (UTC)
Subject: [commit: ghc] master: Allow top level ticked string literals (5bc195a)
Message-ID: <20180306135711.29D283A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/5bc195a2caddc5c29cf24e9c731dd8d5050f2c66/ghc

>---------------------------------------------------------------

commit 5bc195a2caddc5c29cf24e9c731dd8d5050f2c66
Author: Bartosz Nitka <niteria at gmail.com>
Date:   Fri Mar 2 05:33:07 2018 -0800

    Allow top level ticked string literals
    
    This reverts f5b275a239d2554c4da0b7621211642bf3b10650
    and changes the places that looked for `Lit (MachStr _))`
    to use `exprIsMbTickedLitString_maybe` to unwrap ticks as
    necessary.
    Also updated relevant comments.
    
    Test Plan:
    I added 3 new tests that previously reproduced.
    GHC HEAD now builds with -g
    
    Reviewers: simonpj, simonmar, bgamari, hvr, goldfire
    
    Subscribers: rwbarton, thomie, carter
    
    GHC Trac Issues: #14779
    
    Differential Revision: https://phabricator.haskell.org/D4470


>---------------------------------------------------------------

5bc195a2caddc5c29cf24e9c731dd8d5050f2c66
 compiler/coreSyn/CoreLint.hs                       |  6 +-
 compiler/coreSyn/CoreSyn.hs                        | 10 +--
 compiler/coreSyn/CoreUtils.hs                      | 29 ++++++--
 compiler/ghci/ByteCodeGen.hs                       |  4 +-
 compiler/simplCore/CSE.hs                          |  4 +-
 compiler/simplCore/FloatOut.hs                     | 32 ++++-----
 compiler/simplCore/SimplEnv.hs                     |  4 +-
 compiler/simplCore/Simplify.hs                     |  8 +--
 compiler/stgSyn/CoreToStg.hs                       |  7 +-
 .../tests/simplCore/should_compile/T14779a.hs      | 34 +++++++++
 .../tests/simplCore/should_compile/T14779b.hs      | 83 ++++++++++++++++++++++
 testsuite/tests/simplCore/should_compile/all.T     |  6 ++
 testsuite/tests/simplCore/should_run/T14868.hs     |  2 +
 testsuite/tests/simplCore/should_run/T14868.stdout |  1 +
 testsuite/tests/simplCore/should_run/all.T         |  3 +
 15 files changed, 183 insertions(+), 50 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc 5bc195a2caddc5c29cf24e9c731dd8d5050f2c66

From git at git.haskell.org  Tue Mar  6 13:59:43 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue,  6 Mar 2018 13:59:43 +0000 (UTC)
Subject: [commit: ghc] master: Correct -g flag description (9bccfcd)
Message-ID: <20180306135943.76BD23A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/9bccfcdbbf97250ede05a9351de48f8fa1788217/ghc

>---------------------------------------------------------------

commit 9bccfcdbbf97250ede05a9351de48f8fa1788217
Author: Bartosz Nitka <niteria at gmail.com>
Date:   Mon Mar 5 11:10:11 2018 -0800

    Correct -g flag description
    
    Since 7aaeaf81ea95c36fe1dc4da449cf6092a792fd09
    `-g1` and `-g2` are actually different.
    The tutorial below is correct.
    
    Test Plan: harbormaster
    
    Reviewers: bgamari, simonmar
    
    Reviewed By: bgamari
    
    Subscribers: rwbarton, thomie, carter
    
    Differential Revision: https://phabricator.haskell.org/D4471


>---------------------------------------------------------------

9bccfcdbbf97250ede05a9351de48f8fa1788217
 docs/users_guide/debug-info.rst | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/docs/users_guide/debug-info.rst b/docs/users_guide/debug-info.rst
index aca3733..9a3a671 100644
--- a/docs/users_guide/debug-info.rst
+++ b/docs/users_guide/debug-info.rst
@@ -17,8 +17,9 @@ useable by most UNIX debugging tools.
 
     Emit debug information in object code. Currently only DWARF debug
     information is supported on x86-64 and i386. Currently debug levels 0
-    through 3 are accepted, with 0 disabling debug information production.
-    Levels 1 through 3 are functionally equivalent.
+    through 3 are accepted, with 0 disabling debug information production
+    and higher numbers producing richer output. If ⟨n⟩ is omitted level 2
+    is assumed.
 
 
 Tutorial


From git at git.haskell.org  Tue Mar  6 17:29:22 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue,  6 Mar 2018 17:29:22 +0000 (UTC)
Subject: [commit: ghc] ghc-8.4: One final sweep over release notes (6540b71)
Message-ID: <20180306172922.8C8F73A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : ghc-8.4
Link       : http://ghc.haskell.org/trac/ghc/changeset/6540b7113aea04ef7feb3b849861fd4be7c38f1f/ghc

>---------------------------------------------------------------

commit 6540b7113aea04ef7feb3b849861fd4be7c38f1f
Author: Ben Gamari <ben at smart-cactus.org>
Date:   Sun Mar 4 12:42:05 2018 -0500

    One final sweep over release notes


>---------------------------------------------------------------

6540b7113aea04ef7feb3b849861fd4be7c38f1f
 docs/users_guide/8.4.1-notes.rst | 41 ++++------------------------------------
 1 file changed, 4 insertions(+), 37 deletions(-)

diff --git a/docs/users_guide/8.4.1-notes.rst b/docs/users_guide/8.4.1-notes.rst
index 489f4c8..b25d184 100644
--- a/docs/users_guide/8.4.1-notes.rst
+++ b/docs/users_guide/8.4.1-notes.rst
@@ -24,6 +24,10 @@ The highlights, since the 8.2.1 release, are:
 
 - Further improvements in code generation
 
+- Incoporation of library changes including the Phase 2 of the Semigroup-Monoid Proposal
+
+- A variety of Windows compatibility improvements
+
 - Many, many bug fixes.
 
 
@@ -334,43 +338,6 @@ Template Haskell
 - ``Language.Haskell.TH.FamFlavour``, which was deprecated in GHC 8.2,
   has been removed.
 
-``ghc`` library
-~~~~~~~~~~~~~~~
-
-- hsSyn Abstract Syntax Tree (AST) is now extensible via the mechanism described in `Trees that Grow <http://www.jucs.org/jucs_23_1/trees_that_grow/jucs_23_01_0042_0062_najd.pdf>`_
-
-  The main change for users of the GHC API is that the AST is no longer indexed
-  by the type used as the identifier, but by a specific index type, ::
-
-      type GhcPs   = GhcPass 'Parsed      -- Old 'RdrName' type param
-      type GhcRn   = GhcPass 'Renamed     -- Old 'Name' type param
-      type GhcTc   = GhcPass 'Typechecked -- Old 'Id' type para,
-      type GhcTcId = GhcTc                -- Old 'TcId' type param
-
-  The simplest way to support the current GHC as well as earlier ones is to define ::
-
-      #if MIN_VERSION_ghc(8,3,0)
-      type ParseI     = GhcPs
-      type RenameI    = GhcRn
-      type TypecheckI = GhcTc
-      #else
-      type ParseI     = RdrName
-      type RenameI    = Name
-      type TypecheckI = Var
-      #endif
-
-  and then replace all hardcoded index types accordingly. For polymorphic types,
-  the constraint ::
-
-      #if MIN_VERSION_ghc(8,3,0)
-      -- |bundle up the constraints required for a trees that grow pass
-      type IsPass pass = (DataId pass, OutputableBndrId pass, SourceTextX pass)
-      else
-      type IsPass pass = (DataId pass, OutputableBndrId pass)
-      #endif
-
-  can be used.
-
 ``base`` library
 ~~~~~~~~~~~~~~~~
 


From git at git.haskell.org  Tue Mar  6 17:29:32 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue,  6 Mar 2018 17:29:32 +0000 (UTC)
Subject: [commit: ghc] ghc-8.4: Correct -g flag description (2df499b)
Message-ID: <20180306172932.57B5D3A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : ghc-8.4
Link       : http://ghc.haskell.org/trac/ghc/changeset/2df499b429fd5bbe0f72b56948b9fc2161ec9b4c/ghc

>---------------------------------------------------------------

commit 2df499b429fd5bbe0f72b56948b9fc2161ec9b4c
Author: Bartosz Nitka <niteria at gmail.com>
Date:   Mon Mar 5 15:14:36 2018 -0500

    Correct -g flag description
    
    Since 7aaeaf81ea95c36fe1dc4da449cf6092a792fd09
    `-g1` and `-g2` are actually different.
    The tutorial below is correct.
    
    Test Plan: harbormaster
    
    Reviewers: bgamari, simonmar
    
    Reviewed By: bgamari
    
    Subscribers: rwbarton, thomie, carter
    
    Differential Revision: https://phabricator.haskell.org/D4471
    
    (cherry picked from commit 5b1132eefd0a75189b3527486b492c3dffc7bdf1)


>---------------------------------------------------------------

2df499b429fd5bbe0f72b56948b9fc2161ec9b4c
 docs/users_guide/debug-info.rst | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/docs/users_guide/debug-info.rst b/docs/users_guide/debug-info.rst
index 915591a..0b8cb5e 100644
--- a/docs/users_guide/debug-info.rst
+++ b/docs/users_guide/debug-info.rst
@@ -17,8 +17,9 @@ useable by most UNIX debugging tools.
 
     Emit debug information in object code. Currently only DWARF debug
     information is supported on x86-64 and i386. Currently debug levels 0
-    through 3 are accepted, with 0 disabling debug information production.
-    Levels 1 through 3 are functionally equivalent.
+    through 3 are accepted, with 0 disabling debug information production
+    and higher numbers producing richer output. If ⟨n⟩ is omitted level 2
+    is assumed.
 
 
 Tutorial


From git at git.haskell.org  Tue Mar  6 17:29:42 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue,  6 Mar 2018 17:29:42 +0000 (UTC)
Subject: [commit: ghc] ghc-8.4: Fixup include of gmp/config.mk to use new
 location (57b9a43)
Message-ID: <20180306172942.384E23A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : ghc-8.4
Link       : http://ghc.haskell.org/trac/ghc/changeset/57b9a433e13d7062eca4bd8fbae80019a499e973/ghc

>---------------------------------------------------------------

commit 57b9a433e13d7062eca4bd8fbae80019a499e973
Author: Herbert Valerio Riedel <hvr at gnu.org>
Date:   Mon Mar 5 21:13:28 2018 +0100

    Fixup include of gmp/config.mk to use new location
    
    This wasn't spotted rightaway in
    8f0b2f5eadf0fcb47c581907205a9db686214a69
    because the include-site deliberately ignored include-errors as
    a Hack with the justification below:
    
    > Hack. The file gmp/config.mk doesn't exist yet after running ./configure in
    > the toplevel (ghc) directory. To let some toplevel make commands such as
    > sdist go through, right after ./configure, don't consider this an error.
    
    This may have contributed to #14891.
    
    (cherry picked from commit df7ac37d43bdbabbde9b09344f9425e8e5a879ff)


>---------------------------------------------------------------

57b9a433e13d7062eca4bd8fbae80019a499e973
 libraries/integer-gmp/gmp/ghc.mk | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libraries/integer-gmp/gmp/ghc.mk b/libraries/integer-gmp/gmp/ghc.mk
index 794942c..556a271 100644
--- a/libraries/integer-gmp/gmp/ghc.mk
+++ b/libraries/integer-gmp/gmp/ghc.mk
@@ -56,7 +56,7 @@ ifneq "$(CLEANING)" "YES"
 # Hack. The file gmp/config.mk doesn't exist yet after running ./configure in
 # the toplevel (ghc) directory. To let some toplevel make commands such as
 # sdist go through, right after ./configure, don't consider this an error.
--include libraries/integer-gmp/gmp/config.mk
+-include libraries/integer-gmp/dist-install/build/gmp/config.mk
 endif
 
 gmp_CC_OPTS += $(addprefix -I,$(GMP_INCLUDE_DIRS))


From git at git.haskell.org  Tue Mar  6 17:29:51 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue,  6 Mar 2018 17:29:51 +0000 (UTC)
Subject: [commit: ghc] ghc-8.4: Another Cabal submodule bump (201a557)
Message-ID: <20180306172951.E96E13A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : ghc-8.4
Link       : http://ghc.haskell.org/trac/ghc/changeset/201a5570bbc87ee740b63369edbd637141867144/ghc

>---------------------------------------------------------------

commit 201a5570bbc87ee740b63369edbd637141867144
Author: Ben Gamari <ben at smart-cactus.org>
Date:   Tue Mar 6 11:11:51 2018 -0500

    Another Cabal submodule bump


>---------------------------------------------------------------

201a5570bbc87ee740b63369edbd637141867144
 libraries/Cabal | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libraries/Cabal b/libraries/Cabal
index 728ad1a..ccd0c59 160000
--- a/libraries/Cabal
+++ b/libraries/Cabal
@@ -1 +1 @@
-Subproject commit 728ad1a1e066da453ae13ee479629c00d8c2f32d
+Subproject commit ccd0c59bec88b179c06b65df3247d8664b38e44e


From git at git.haskell.org  Tue Mar  6 17:30:03 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue,  6 Mar 2018 17:30:03 +0000 (UTC)
Subject: [commit: ghc] ghc-8.4: Allow top level ticked string literals
 (2753d89)
Message-ID: <20180306173003.985993A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : ghc-8.4
Link       : http://ghc.haskell.org/trac/ghc/changeset/2753d8903129ffec94253f99c3904248274053cd/ghc

>---------------------------------------------------------------

commit 2753d8903129ffec94253f99c3904248274053cd
Author: Bartosz Nitka <niteria at gmail.com>
Date:   Fri Mar 2 05:33:07 2018 -0800

    Allow top level ticked string literals
    
    This reverts f5b275a239d2554c4da0b7621211642bf3b10650
    and changes the places that looked for `Lit (MachStr _))`
    to use `exprIsMbTickedLitString_maybe` to unwrap ticks as
    necessary.
    Also updated relevant comments.
    
    Test Plan:
    I added 3 new tests that previously reproduced.
    GHC HEAD now builds with -g
    
    Reviewers: simonpj, simonmar, bgamari, hvr, goldfire
    
    Subscribers: rwbarton, thomie, carter
    
    GHC Trac Issues: #14779
    
    Differential Revision: https://phabricator.haskell.org/D4470
    
    (cherry picked from commit 5bc195a2caddc5c29cf24e9c731dd8d5050f2c66)


>---------------------------------------------------------------

2753d8903129ffec94253f99c3904248274053cd
 compiler/coreSyn/CoreLint.hs                       |  6 +-
 compiler/coreSyn/CoreSyn.hs                        | 10 +--
 compiler/coreSyn/CoreUtils.hs                      | 29 ++++++--
 compiler/ghci/ByteCodeGen.hs                       |  4 +-
 compiler/simplCore/CSE.hs                          |  4 +-
 compiler/simplCore/FloatOut.hs                     | 32 ++++-----
 compiler/simplCore/SimplEnv.hs                     |  4 +-
 compiler/simplCore/Simplify.hs                     |  8 +--
 compiler/stgSyn/CoreToStg.hs                       |  7 +-
 .../tests/simplCore/should_compile/T14779a.hs      | 34 +++++++++
 .../tests/simplCore/should_compile/T14779b.hs      | 83 ++++++++++++++++++++++
 testsuite/tests/simplCore/should_compile/all.T     |  6 ++
 testsuite/tests/simplCore/should_run/T14868.hs     |  2 +
 testsuite/tests/simplCore/should_run/T14868.stdout |  1 +
 testsuite/tests/simplCore/should_run/all.T         |  3 +
 15 files changed, 183 insertions(+), 50 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc 2753d8903129ffec94253f99c3904248274053cd

From git at git.haskell.org  Tue Mar  6 17:30:18 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue,  6 Mar 2018 17:30:18 +0000 (UTC)
Subject: [commit: ghc] ghc-8.4: add CCX=$(CXX) to integer-gmp (76af028)
Message-ID: <20180306173018.57A643A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : ghc-8.4
Link       : http://ghc.haskell.org/trac/ghc/changeset/76af02833913942defee5962669ac67a8ffb1762/ghc

>---------------------------------------------------------------

commit 76af02833913942defee5962669ac67a8ffb1762
Author: Moritz Angermann <moritz.angermann at gmail.com>
Date:   Tue Mar 6 11:20:22 2018 +0800

    add CCX=$(CXX) to integer-gmp
    
    Summary:
    This came up when trying to build GHC HEAD with nix. We
    do not set CCX for integer-gmp when running ./configure. We do
    this however for libffi.
    
    The result is, that if CCX is not set, we default to the system
    one, of which there might be none (as in nixos's case).  This
    will not show on a debian+nix or similar setup, where the system
    `cxx` is still in place, and only shows up when the system tries
    hard to sandbox everything (even cxx) as nixOS does.
    
    We use `CXX`, which is set to either `clang` or `CC_STAGE1`, and
    also usedfor `CC`, similar to what we do for libffi.c
    
    Test Plan: ./validate
    
    Reviewers: bgamari, hvr
    
    Reviewed By: hvr
    
    Subscribers: rwbarton, thomie, carter
    
    Differential Revision: https://phabricator.haskell.org/D4473
    
    (cherry picked from commit cf5bc96e1b023275ec3c0399f3345ceebbc48df0)


>---------------------------------------------------------------

76af02833913942defee5962669ac67a8ffb1762
 libraries/integer-gmp/gmp/ghc.mk | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libraries/integer-gmp/gmp/ghc.mk b/libraries/integer-gmp/gmp/ghc.mk
index 556a271..f18e27d 100644
--- a/libraries/integer-gmp/gmp/ghc.mk
+++ b/libraries/integer-gmp/gmp/ghc.mk
@@ -131,7 +131,7 @@ libraries/integer-gmp/gmp/libgmp.a libraries/integer-gmp/gmp/gmp.h:
 	#       `./configure`, not `HOSTPLATFORM`: the 'host' on which GMP will
 	#       run is the 'target' platform of the compiler we're building.
 	cd libraries/integer-gmp/gmp/gmpbuild; \
-	    CC=$(CCX) NM=$(NM) AR=$(AR_STAGE1) ./configure \
+	    CC=$(CCX) CXX=$(CCX) NM=$(NM) AR=$(AR_STAGE1) ./configure \
 	          --enable-shared=no \
 	          --host=$(TARGETPLATFORM) --build=$(BUILDPLATFORM)
 	$(MAKE) -C libraries/integer-gmp/gmp/gmpbuild MAKEFLAGS=


From git at git.haskell.org  Tue Mar  6 17:30:28 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue,  6 Mar 2018 17:30:28 +0000 (UTC)
Subject: [commit: ghc] ghc-8.4: Bump hsc2hs submodule (3ba3fa6)
Message-ID: <20180306173028.515FC3A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : ghc-8.4
Link       : http://ghc.haskell.org/trac/ghc/changeset/3ba3fa6a111f0fe72a7d556d0bd76137dc8b6144/ghc

>---------------------------------------------------------------

commit 3ba3fa6a111f0fe72a7d556d0bd76137dc8b6144
Author: Ben Gamari <ben at smart-cactus.org>
Date:   Tue Mar 6 11:48:41 2018 -0500

    Bump hsc2hs submodule


>---------------------------------------------------------------

3ba3fa6a111f0fe72a7d556d0bd76137dc8b6144
 utils/hsc2hs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/utils/hsc2hs b/utils/hsc2hs
index 9483ad1..16ee80a 160000
--- a/utils/hsc2hs
+++ b/utils/hsc2hs
@@ -1 +1 @@
-Subproject commit 9483ad10064fbbb97ab525280623826b1ef63959
+Subproject commit 16ee80ad2d3f6fac23bf81357a3cd2793e5a1315


From git at git.haskell.org  Tue Mar  6 17:30:38 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue,  6 Mar 2018 17:30:38 +0000 (UTC)
Subject: [commit: ghc] ghc-8.4: Set RELEASE=YES, version 8.4.1 (4b6c3b6)
Message-ID: <20180306173038.1D8123A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : ghc-8.4
Link       : http://ghc.haskell.org/trac/ghc/changeset/4b6c3b6f15b0b4b7cee853856b45b317817e7351/ghc

>---------------------------------------------------------------

commit 4b6c3b6f15b0b4b7cee853856b45b317817e7351
Author: Ben Gamari <ben at smart-cactus.org>
Date:   Sun Mar 4 13:53:54 2018 -0500

    Set RELEASE=YES, version 8.4.1


>---------------------------------------------------------------

4b6c3b6f15b0b4b7cee853856b45b317817e7351
 configure.ac | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/configure.ac b/configure.ac
index 57d76b4..30241a5 100644
--- a/configure.ac
+++ b/configure.ac
@@ -13,10 +13,10 @@ dnl
 # see what flags are available. (Better yet, read the documentation!)
 #
 
-AC_INIT([The Glorious Glasgow Haskell Compilation System], [8.4.0], [glasgow-haskell-bugs at haskell.org], [ghc-AC_PACKAGE_VERSION])
+AC_INIT([The Glorious Glasgow Haskell Compilation System], [8.4.1], [glasgow-haskell-bugs at haskell.org], [ghc-AC_PACKAGE_VERSION])
 
 # Set this to YES for a released version, otherwise NO
-: ${RELEASE=NO}
+: ${RELEASE=YES}
 
 # The primary version (e.g. 7.5, 7.4.1) is set in the AC_INIT line
 # above.  If this is not a released version, then we will append the


From git at git.haskell.org  Tue Mar  6 18:33:35 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue,  6 Mar 2018 18:33:35 +0000 (UTC)
Subject: [commit: ghc] master: cmm/: Avoid using lazy left folds (64c0af7)
Message-ID: <20180306183335.98ECF3A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/64c0af7517148316b259300b851b966cfbcf3eaf/ghc

>---------------------------------------------------------------

commit 64c0af7517148316b259300b851b966cfbcf3eaf
Author: Michal Terepeta <michal.terepeta at gmail.com>
Date:   Mon Mar 5 15:16:02 2018 -0500

    cmm/: Avoid using lazy left folds
    
    This basically replaces all uses of `foldl` with `foldl'`. I've looked
    at all the call sites and there doesn't seem to be any reason to prefer
    the lazy version.
    
    Signed-off-by: Michal Terepeta <michal.terepeta at gmail.com>
    
    Test Plan: ./validate
    
    Reviewers: bgamari, simonmar
    
    Reviewed By: bgamari
    
    Subscribers: rwbarton, thomie, carter
    
    Differential Revision: https://phabricator.haskell.org/D4463


>---------------------------------------------------------------

64c0af7517148316b259300b851b966cfbcf3eaf
 compiler/cmm/CmmBuildInfoTables.hs | 24 +++++++++++++-----------
 compiler/cmm/CmmCommonBlockElim.hs |  3 ++-
 compiler/cmm/CmmContFlowOpt.hs     |  3 ++-
 compiler/cmm/CmmLayoutStack.hs     |  4 ++--
 compiler/cmm/CmmProcPoint.hs       |  9 +++++----
 compiler/cmm/CmmSink.hs            |  5 +++--
 6 files changed, 27 insertions(+), 21 deletions(-)

diff --git a/compiler/cmm/CmmBuildInfoTables.hs b/compiler/cmm/CmmBuildInfoTables.hs
index dc5cfd6..ae192e5 100644
--- a/compiler/cmm/CmmBuildInfoTables.hs
+++ b/compiler/cmm/CmmBuildInfoTables.hs
@@ -119,11 +119,13 @@ cafAnal cmmGraph = analyzeCmmBwd cafLattice cafTransfers cmmGraph mapEmpty
 
 -- Description of the SRT for a given module.
 -- Note that this SRT may grow as we greedily add new CAFs to it.
-data TopSRT = TopSRT { lbl      :: CLabel
-                     , next_elt :: Int -- the next entry in the table
-                     , rev_elts :: [CLabel]
-                     , elt_map  :: Map CLabel Int }
-                        -- map: CLabel -> its last entry in the table
+data TopSRT = TopSRT
+  { lbl      :: CLabel
+  , next_elt :: {-# UNPACK #-} !Int -- the next entry in the table
+  , rev_elts :: [CLabel]
+  , elt_map  :: !(Map CLabel Int) -- CLabel -> its last entry in the table
+  }
+
 instance Outputable TopSRT where
   ppr (TopSRT lbl next elts eltmap) =
     text "TopSRT:" <+> ppr lbl
@@ -176,7 +178,7 @@ buildSRT dflags topSRT cafs =
                  do localSRTs <- procpointSRT dflags (lbl topSRT) (elt_map topSRT) cafs
                     return (topSRT, localSRTs)
            in if cafs `lengthExceeds` maxBmpSize dflags then
-                mkSRT (foldl add_if_missing topSRT cafs)
+                mkSRT (foldl' add_if_missing topSRT cafs)
               else -- make sure all the cafs are near the bottom of the srt
                 mkSRT (add_if_too_far topSRT cafs)
          add_if_missing srt caf =
@@ -269,14 +271,14 @@ localCAFInfo cafEnv proc@(CmmProc _ top_l _ (CmmGraph {g_entry=entry})) =
 -- To do this replacement efficiently, we gather strongly connected
 -- components, then we sort the components in topological order.
 mkTopCAFInfo :: [(CAFSet, Maybe CLabel)] -> Map CLabel CAFSet
-mkTopCAFInfo localCAFs = foldl addToTop Map.empty g
+mkTopCAFInfo localCAFs = foldl' addToTop Map.empty g
   where
-        addToTop env (AcyclicSCC (l, cafset)) =
+        addToTop !env (AcyclicSCC (l, cafset)) =
           Map.insert l (flatten env cafset) env
-        addToTop env (CyclicSCC nodes) =
+        addToTop !env (CyclicSCC nodes) =
           let (lbls, cafsets) = unzip nodes
-              cafset  = foldr Set.delete (foldl Set.union Set.empty cafsets) lbls
-          in foldl (\env l -> Map.insert l (flatten env cafset) env) env lbls
+              cafset = Set.unions cafsets `Set.difference` Set.fromList lbls
+          in foldl' (\env l -> Map.insert l (flatten env cafset) env) env lbls
 
         g = stronglyConnCompFromEdgedVerticesOrd
               [ DigraphNode (l,cafs) l (Set.elems cafs)
diff --git a/compiler/cmm/CmmCommonBlockElim.hs b/compiler/cmm/CmmCommonBlockElim.hs
index ba3b1c8..fce8f7d 100644
--- a/compiler/cmm/CmmCommonBlockElim.hs
+++ b/compiler/cmm/CmmCommonBlockElim.hs
@@ -29,6 +29,7 @@ import UniqDFM
 import qualified TrieMap as TM
 import Unique
 import Control.Arrow (first, second)
+import Data.List (foldl')
 
 -- -----------------------------------------------------------------------------
 -- Eliminate common blocks
@@ -173,7 +174,7 @@ hash_block block =
         hash_tgt (ForeignTarget e _) = hash_e e
         hash_tgt (PrimTarget _) = 31 -- lots of these
 
-        hash_list f = foldl (\z x -> f x + z) (0::Word32)
+        hash_list f = foldl' (\z x -> f x + z) (0::Word32)
 
         cvt = fromInteger . toInteger
 
diff --git a/compiler/cmm/CmmContFlowOpt.hs b/compiler/cmm/CmmContFlowOpt.hs
index 8863012..da365cf 100644
--- a/compiler/cmm/CmmContFlowOpt.hs
+++ b/compiler/cmm/CmmContFlowOpt.hs
@@ -24,6 +24,7 @@ import Panic
 import Util
 
 import Control.Monad
+import Data.List
 
 
 -- Note [What is shortcutting]
@@ -177,7 +178,7 @@ blockConcat splitting_procs g at CmmGraph { g_entry = entry_id }
      -- a map of blocks. We process each element from blocks and update
      -- blockmap accordingly
      blocks = postorderDfs g
-     blockmap = foldr addBlock emptyBody blocks
+     blockmap = foldl' (flip addBlock) emptyBody blocks
 
      -- Accumulator contains three components:
      --  * map of blocks in a graph
diff --git a/compiler/cmm/CmmLayoutStack.hs b/compiler/cmm/CmmLayoutStack.hs
index 2602dc8..3f16334 100644
--- a/compiler/cmm/CmmLayoutStack.hs
+++ b/compiler/cmm/CmmLayoutStack.hs
@@ -37,7 +37,7 @@ import qualified Data.Set as Set
 import Control.Monad.Fix
 import Data.Array as Array
 import Data.Bits
-import Data.List (nub)
+import Data.List (nub, foldl')
 
 {- Note [Stack Layout]
 
@@ -322,7 +322,7 @@ layout dflags procpoints liveness entry entry_args final_stackmaps final_sp_high
        --    Sp = Sp + sp_off -- Sp adjustment goes here
        --    last1            -- the last node
        --
-       let middle_pre = blockToList $ foldl blockSnoc middle0 middle1
+       let middle_pre = blockToList $ foldl' blockSnoc middle0 middle1
 
        let final_blocks =
                manifestSp dflags final_stackmaps stack0 sp0 final_sp_high
diff --git a/compiler/cmm/CmmProcPoint.hs b/compiler/cmm/CmmProcPoint.hs
index 3459284..eeae960 100644
--- a/compiler/cmm/CmmProcPoint.hs
+++ b/compiler/cmm/CmmProcPoint.hs
@@ -330,7 +330,7 @@ splitAtProcPoints dflags entry_label callPPs procPoints procMap
                   -- replace branches to procpoints with branches to jumps
                   blockEnv'' = toBlockMap $ replaceBranches jumpEnv $ ofBlockMap ppId blockEnv'
                   -- add the jump blocks to the graph
-                  blockEnv''' = foldl (flip insertBlock) blockEnv'' jumpBlocks
+                  blockEnv''' = foldl' (flip insertBlock) blockEnv'' jumpBlocks
               let g' = ofBlockMap ppId blockEnv'''
               -- pprTrace "g' pre jumps" (ppr g') $ do
               return (mapInsert ppId g' newGraphEnv)
@@ -373,9 +373,10 @@ splitAtProcPoints dflags entry_label callPPs procPoints procMap
      -- call sites.  Here, we sort them in reverse order -- it gets
      -- reversed later.
      let (_, block_order) =
-             foldl add_block_num (0::Int, mapEmpty :: LabelMap Int)
-                   (postorderDfs g)
-         add_block_num (i, map) block = (i+1, mapInsert (entryLabel block) i map)
+             foldl' add_block_num (0::Int, mapEmpty :: LabelMap Int)
+                    (postorderDfs g)
+         add_block_num (!i, !map) block =
+           (i + 1, mapInsert (entryLabel block) i map)
          sort_fn (bid, _) (bid', _) =
            compare (expectJust "block_order" $ mapLookup bid  block_order)
                    (expectJust "block_order" $ mapLookup bid' block_order)
diff --git a/compiler/cmm/CmmSink.hs b/compiler/cmm/CmmSink.hs
index 464a041..487f0bc 100644
--- a/compiler/cmm/CmmSink.hs
+++ b/compiler/cmm/CmmSink.hs
@@ -24,6 +24,7 @@ import PprCmm ()
 import qualified Data.IntSet as IntSet
 import Data.List (partition)
 import qualified Data.Set as Set
+import Data.List
 import Data.Maybe
 
 -- Compact sets for membership tests of local variables.
@@ -233,7 +234,7 @@ cmmSink dflags graph = ofBlockList (g_entry graph) $ sink mapEmpty $ blocks
 
             live_rhs = foldRegsUsed dflags extendRegSet emptyRegSet rhs
 
-      final_middle = foldl blockSnoc middle' dropped_last
+      final_middle = foldl' blockSnoc middle' dropped_last
 
       sunk' = mapUnion sunk $
                  mapFromList [ (l, filterAssignments dflags (getLive l) assigs'')
@@ -343,7 +344,7 @@ walk dflags nodes assigs = go nodes emptyBlock assigs
       (dropped, as') = dropAssignmentsSimple dflags
                           (\a -> conflicts dflags a node2) as1
 
-      block' = foldl blockSnoc block dropped `blockSnoc` node2
+      block' = foldl' blockSnoc block dropped `blockSnoc` node2
 
 
 --


From git at git.haskell.org  Tue Mar  6 18:33:50 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue,  6 Mar 2018 18:33:50 +0000 (UTC)
Subject: [commit: ghc] master: Make accumArray and accum stricter (08345bd)
Message-ID: <20180306183350.2DB0A3A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/08345bd0e8d237ec3929aaee7613c4f76e07e131/ghc

>---------------------------------------------------------------

commit 08345bd0e8d237ec3929aaee7613c4f76e07e131
Author: David Feuer <david.feuer at gmail.com>
Date:   Mon Mar 5 15:18:05 2018 -0500

    Make accumArray and accum stricter
    
    `accumArray` was lazier than documented. `accum` did not have
    documented strictness. The extra laziness allowed thunks to build
    up in the array. Force the results of applying the accumulating
    function to resolve.
    
    Reviewers: hvr, bgamari
    
    Reviewed By: bgamari
    
    Subscribers: alpmestan, rwbarton, thomie, carter
    
    GHC Trac Issues: #14785
    
    Differential Revision: https://phabricator.haskell.org/D4403


>---------------------------------------------------------------

08345bd0e8d237ec3929aaee7613c4f76e07e131
 libraries/base/GHC/Arr.hs | 30 +++++++++++++++++++++++-------
 1 file changed, 23 insertions(+), 7 deletions(-)

diff --git a/libraries/base/GHC/Arr.hs b/libraries/base/GHC/Arr.hs
index adfd602..3698852 100644
--- a/libraries/base/GHC/Arr.hs
+++ b/libraries/base/GHC/Arr.hs
@@ -1,5 +1,6 @@
 {-# LANGUAGE Unsafe #-}
 {-# LANGUAGE NoImplicitPrelude, MagicHash, UnboxedTuples, RoleAnnotations #-}
+{-# LANGUAGE BangPatterns #-}
 {-# OPTIONS_HADDOCK hide #-}
 
 -----------------------------------------------------------------------------
@@ -505,7 +506,7 @@ listArray (l,u) es = runST (ST $ \s1# ->
 -- | The value at the given index in an array.
 {-# INLINE (!) #-}
 (!) :: Ix i => Array i e -> i -> e
-arr@(Array l u n _) ! i = unsafeAt arr $ safeIndex (l,u) n i
+(!) arr@(Array l u n _) i = unsafeAt arr $ safeIndex (l,u) n i
 
 {-# INLINE safeRangeSize #-}
 safeRangeSize :: Ix i => (i, i) -> Int
@@ -636,6 +637,7 @@ assocs arr@(Array l u _ _) =
 -- | The 'accumArray' function deals with repeated indices in the association
 -- list using an /accumulating function/ which combines the values of
 -- associations with the same index.
+--
 -- For example, given a list of values of some index type, @hist@
 -- produces a histogram of the number of occurrences of each index within
 -- a specified range:
@@ -643,10 +645,10 @@ assocs arr@(Array l u _ _) =
 -- > hist :: (Ix a, Num b) => (a,a) -> [a] -> Array a b
 -- > hist bnds is = accumArray (+) 0 bnds [(i, 1) | i<-is, inRange bnds i]
 --
--- If the accumulating function is strict, then 'accumArray' is strict in
--- the values, as well as the indices, in the association list.  Thus,
--- unlike ordinary arrays built with 'array', accumulated arrays should
--- not in general be recursive.
+-- @accumArray@ is strict in each result of applying the accumulating
+-- function, although it is lazy in the initial value. Thus, unlike
+-- arrays built with 'array', accumulated arrays should not in general
+-- be recursive.
 {-# INLINE accumArray #-}
 accumArray :: Ix i
         => (e -> a -> e)        -- ^ accumulating function
@@ -667,7 +669,7 @@ unsafeAccumArray f initial b ies = unsafeAccumArray' f initial b (rangeSize b) i
 unsafeAccumArray' :: (e -> a -> e) -> e -> (i,i) -> Int -> [(Int, a)] -> Array i e
 unsafeAccumArray' f initial (l,u) n@(I# n#) ies = runST (ST $ \s1# ->
     case newArray# n# initial s1#          of { (# s2#, marr# #) ->
-    foldr (adjust f marr#) (done l u n marr#) ies s2# })
+    foldr (adjust' f marr#) (done l u n marr#) ies s2# })
 
 {-# INLINE adjust #-}
 adjust :: (e -> a -> e) -> MutableArray# s e -> (Int, a) -> STRep s b -> STRep s b
@@ -678,6 +680,18 @@ adjust f marr# (I# i#, new) next
                     case writeArray# marr# i# (f old new) s2# of
                         s3# -> next s3#
 
+{-# INLINE adjust' #-}
+adjust' :: (e -> a -> e)
+        -> MutableArray# s e
+        -> (Int, a)
+        -> STRep s b -> STRep s b
+adjust' f marr# (I# i#, new) next
+  = \s1# -> case readArray# marr# i# s1# of
+                (# s2#, old #) ->
+                    let !combined = f old new
+                    in next (writeArray# marr# i# combined s2#)
+
+
 -- | Constructs an array identical to the first argument except that it has
 -- been updated by the associations in the right argument.
 -- For example, if @m@ is a 1-origin, @n@ by @n@ matrix, then
@@ -706,6 +720,8 @@ unsafeReplace arr ies = runST (do
 --
 -- > accumArray f z b = accum f (array b [(i, z) | i <- range b])
 --
+-- @accum@ is strict in all the results of applying the accumulation.
+-- However, it is lazy in the initial values of the array.
 {-# INLINE accum #-}
 accum :: Ix i => (e -> a -> e) -> Array i e -> [(i, a)] -> Array i e
 accum f arr@(Array l u n _) ies =
@@ -715,7 +731,7 @@ accum f arr@(Array l u n _) ies =
 unsafeAccum :: (e -> a -> e) -> Array i e -> [(Int, a)] -> Array i e
 unsafeAccum f arr ies = runST (do
     STArray l u n marr# <- thawSTArray arr
-    ST (foldr (adjust f marr#) (done l u n marr#) ies))
+    ST (foldr (adjust' f marr#) (done l u n marr#) ies))
 
 {-# INLINE [1] amap #-}  -- See Note [amap]
 amap :: (a -> b) -> Array i a -> Array i b


From git at git.haskell.org  Tue Mar  6 18:34:05 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue,  6 Mar 2018 18:34:05 +0000 (UTC)
Subject: [commit: ghc] master: Bump nofib submodule (1488591)
Message-ID: <20180306183405.929F53A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/1488591ac595d1b7be39345cc390737ea9a65fe3/ghc

>---------------------------------------------------------------

commit 1488591ac595d1b7be39345cc390737ea9a65fe3
Author: Ben Gamari <ben at smart-cactus.org>
Date:   Mon Mar 5 15:30:25 2018 -0500

    Bump nofib submodule


>---------------------------------------------------------------

1488591ac595d1b7be39345cc390737ea9a65fe3
 nofib | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/nofib b/nofib
index ef4f8dc..1364fe6 160000
--- a/nofib
+++ b/nofib
@@ -1 +1 @@
-Subproject commit ef4f8dc8ef51ce3353b76a0761c1a09e5ff30b67
+Subproject commit 1364fe623f9216108a285a8804a27bdd8dfea3c4


From git at git.haskell.org  Tue Mar  6 18:34:21 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue,  6 Mar 2018 18:34:21 +0000 (UTC)
Subject: [commit: ghc] master: Fix interpreter with profiling (488d63d)
Message-ID: <20180306183421.11B673A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/488d63d6899d223ef87c26c218f0cf81ac670a90/ghc

>---------------------------------------------------------------

commit 488d63d6899d223ef87c26c218f0cf81ac670a90
Author: Simon Marlow <marlowsd at gmail.com>
Date:   Mon Mar 5 15:12:57 2018 -0500

    Fix interpreter with profiling
    
    This was broken by D3746 and/or D3809, but unfortunately we didn't
    notice because CI at the time wasn't building the profiling way.
    
    Test Plan:
    ```
    cd testsuite/test/profiling/should_run
    make WAY=ghci-ext-prof
    ```
    
    Reviewers: bgamari, michalt, hvr, erikd
    
    Subscribers: rwbarton, thomie, carter
    
    GHC Trac Issues: #14705
    
    Differential Revision: https://phabricator.haskell.org/D4437


>---------------------------------------------------------------

488d63d6899d223ef87c26c218f0cf81ac670a90
 compiler/codeGen/StgCmmBind.hs                    | 14 +++++++-----
 compiler/codeGen/StgCmmCon.hs                     |  3 +--
 compiler/codeGen/StgCmmLayout.hs                  | 27 ++++++++++++++++-------
 compiler/ghci/ByteCodeGen.hs                      | 11 ++++-----
 testsuite/tests/codeGen/should_run/T13825-unit.hs |  2 +-
 testsuite/tests/profiling/should_run/all.T        |  6 ++---
 6 files changed, 35 insertions(+), 28 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc 488d63d6899d223ef87c26c218f0cf81ac670a90

From git at git.haskell.org  Tue Mar  6 19:02:14 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue,  6 Mar 2018 19:02:14 +0000 (UTC)
Subject: [commit: ghc] ghc-8.4: forkProcess: fix task mutex release order
 (0dc2a35)
Message-ID: <20180306190214.11F543A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : ghc-8.4
Link       : http://ghc.haskell.org/trac/ghc/changeset/0dc2a358a954b0b858e91843ade52bb0a28c392d/ghc

>---------------------------------------------------------------

commit 0dc2a358a954b0b858e91843ade52bb0a28c392d
Author: Ömer Sinan Ağacan <omeragacan at gmail.com>
Date:   Fri Mar 2 11:15:03 2018 -0500

    forkProcess: fix task mutex release order
    
    `all_tasks_mutex` should be released before calling `releaseCapability_`
    in the parent process as `releaseCapability_` spawns worker tasks in
    some cases.
    
    Reviewers: bgamari, erikd, simonmar
    
    Subscribers: rwbarton, thomie, carter
    
    GHC Trac Issues: #14538
    
    Differential Revision: https://phabricator.haskell.org/D4460
    
    (cherry picked from commit e261b8523eb547b93b8b9e194bc2566350e7cc60)


>---------------------------------------------------------------

0dc2a358a954b0b858e91843ade52bb0a28c392d
 rts/Schedule.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/rts/Schedule.c b/rts/Schedule.c
index 8002ac3..828a35f 100644
--- a/rts/Schedule.c
+++ b/rts/Schedule.c
@@ -2004,15 +2004,15 @@ forkProcess(HsStablePtr *entry
         RELEASE_LOCK(&stable_mutex);
         RELEASE_LOCK(&task->lock);
 
+#if defined(THREADED_RTS)
+        RELEASE_LOCK(&all_tasks_mutex);
+#endif
+
         for (i=0; i < n_capabilities; i++) {
             releaseCapability_(capabilities[i],false);
             RELEASE_LOCK(&capabilities[i]->lock);
         }
 
-#if defined(THREADED_RTS)
-        RELEASE_LOCK(&all_tasks_mutex);
-#endif
-
         boundTaskExiting(task);
 
         // just return the pid


From git at git.haskell.org  Tue Mar  6 19:02:23 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue,  6 Mar 2018 19:02:23 +0000 (UTC)
Subject: [commit: ghc] ghc-8.4: Fix interpreter with profiling (0a3e2f3)
Message-ID: <20180306190223.EF6313A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : ghc-8.4
Link       : http://ghc.haskell.org/trac/ghc/changeset/0a3e2f324dbd525d626ebd3d97e8ffa1cf2f0ffb/ghc

>---------------------------------------------------------------

commit 0a3e2f324dbd525d626ebd3d97e8ffa1cf2f0ffb
Author: Simon Marlow <marlowsd at gmail.com>
Date:   Mon Mar 5 15:12:57 2018 -0500

    Fix interpreter with profiling
    
    This was broken by D3746 and/or D3809, but unfortunately we didn't
    notice because CI at the time wasn't building the profiling way.
    
    Test Plan:
    ```
    cd testsuite/test/profiling/should_run
    make WAY=ghci-ext-prof
    ```
    
    Reviewers: bgamari, michalt, hvr, erikd
    
    Subscribers: rwbarton, thomie, carter
    
    GHC Trac Issues: #14705
    
    Differential Revision: https://phabricator.haskell.org/D4437
    
    (cherry picked from commit 488d63d6899d223ef87c26c218f0cf81ac670a90)


>---------------------------------------------------------------

0a3e2f324dbd525d626ebd3d97e8ffa1cf2f0ffb
 compiler/codeGen/StgCmmBind.hs                    | 14 +++++++-----
 compiler/codeGen/StgCmmCon.hs                     |  3 +--
 compiler/codeGen/StgCmmLayout.hs                  | 27 ++++++++++++++++-------
 compiler/ghci/ByteCodeGen.hs                      | 11 ++++-----
 testsuite/tests/codeGen/should_run/T13825-unit.hs |  2 +-
 5 files changed, 33 insertions(+), 24 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc 0a3e2f324dbd525d626ebd3d97e8ffa1cf2f0ffb

From git at git.haskell.org  Wed Mar  7 05:39:09 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Wed,  7 Mar 2018 05:39:09 +0000 (UTC)
Subject: [commit: ghc] wip/angerman/win32-cross-2: Adds
 iserv-proxy/cabal.project (31a01e7)
Message-ID: <20180307053909.6B6AC3A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/angerman/win32-cross-2
Link       : http://ghc.haskell.org/trac/ghc/changeset/31a01e7e71c6dd4a59d3d44ad09e5e1e157dee8c/ghc

>---------------------------------------------------------------

commit 31a01e7e71c6dd4a59d3d44ad09e5e1e157dee8c
Author: Moritz Angermann <moritz.angermann at gmail.com>
Date:   Wed Mar 7 11:01:23 2018 +0800

    Adds iserv-proxy/cabal.project


>---------------------------------------------------------------

31a01e7e71c6dd4a59d3d44ad09e5e1e157dee8c
 utils/iserv-proxy/cabal.project | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/utils/iserv-proxy/cabal.project b/utils/iserv-proxy/cabal.project
new file mode 100644
index 0000000..2e6cd12
--- /dev/null
+++ b/utils/iserv-proxy/cabal.project
@@ -0,0 +1,4 @@
+packages: . ../../libraries/libiserv
+
+package libiserv
+  flags: +network


From git at git.haskell.org  Wed Mar  7 05:39:12 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Wed,  7 Mar 2018 05:39:12 +0000 (UTC)
Subject: [commit: ghc] wip/angerman/win32-cross-2: Adds iserv-slave (via CLI)
 (8fc0614)
Message-ID: <20180307053912.D598A3A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/angerman/win32-cross-2
Link       : http://ghc.haskell.org/trac/ghc/changeset/8fc0614f46434b786cc3a746e329ccc403bff72f/ghc

>---------------------------------------------------------------

commit 8fc0614f46434b786cc3a746e329ccc403bff72f
Author: Moritz Angermann <moritz.angermann at gmail.com>
Date:   Wed Mar 7 13:38:09 2018 +0800

    Adds iserv-slave (via CLI)


>---------------------------------------------------------------

8fc0614f46434b786cc3a746e329ccc403bff72f
 utils/{iserv-proxy => iserv-slave}/cabal.project |  0
 utils/iserv-slave/iserv-slave.cabal              | 20 ++++++++++++++++
 utils/iserv-slave/src/Cli.hs                     | 30 ++++++++++++++++++++++++
 3 files changed, 50 insertions(+)

diff --git a/utils/iserv-proxy/cabal.project b/utils/iserv-slave/cabal.project
similarity index 100%
copy from utils/iserv-proxy/cabal.project
copy to utils/iserv-slave/cabal.project
diff --git a/utils/iserv-slave/iserv-slave.cabal b/utils/iserv-slave/iserv-slave.cabal
new file mode 100644
index 0000000..66a2a32
--- /dev/null
+++ b/utils/iserv-slave/iserv-slave.cabal
@@ -0,0 +1,20 @@
+Name: iserv-slave
+Version: 8.5
+Copyright: XXX
+License: BSD3
+-- XXX License-File: LICENSE
+Author: XXX
+Maintainer: XXX
+Synopsis: iserv allows GHC to delegate Tempalte Haskell computations
+Description:
+Category: Development
+build-type: Simple
+cabal-version: >=1.10
+
+Executable iserv-slave
+   Default-Language: Haskell2010
+   Main-Is: Cli.hs
+   Hs-Source-Dirs: src
+   Build-Depends:
+                  base       >= 4   && < 5,
+                  libiserv   == 8.5
diff --git a/utils/iserv-slave/src/Cli.hs b/utils/iserv-slave/src/Cli.hs
new file mode 100644
index 0000000..8a3a34f
--- /dev/null
+++ b/utils/iserv-slave/src/Cli.hs
@@ -0,0 +1,30 @@
+module Main where
+
+import System.Environment (getProgName, getArgs)
+import System.Exit        (die)
+import Remote.Slave       (startSlave')
+
+main :: IO ()
+main = getArgs >>= startSlave
+
+dieWithUsage :: IO a
+dieWithUsage = do
+	prog <- getProgName
+	die $ prog  ++ ": " ++ msg
+  where
+  	msg = "usage: iserv-slave /path/to/storage PORT [-v]"
+
+startSlave :: [String] -> IO ()
+startSlave args0
+	| "--help" `elem` args0 = dieWithUsage
+	| otherwise = do
+		(path, port, rest) <- case args0 of
+			arg0:arg1:rest -> return (arg0, read arg1, rest)
+			_              -> dieWithUsage
+		verbose <- case rest of
+			["-v"] -> return True
+			[]     -> return False
+			_      -> dieWithUsage
+
+		startSlave' verbose path port
+


From git at git.haskell.org  Wed Mar  7 05:39:15 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Wed,  7 Mar 2018 05:39:15 +0000 (UTC)
Subject: [commit: ghc] wip/angerman/win32-cross-2: Better logging in
 iserv-remote (c5fd54a)
Message-ID: <20180307053915.A57963A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/angerman/win32-cross-2
Link       : http://ghc.haskell.org/trac/ghc/changeset/c5fd54a15c919a4515aefb045271be1042d35772/ghc

>---------------------------------------------------------------

commit c5fd54a15c919a4515aefb045271be1042d35772
Author: Moritz Angermann <moritz.angermann at gmail.com>
Date:   Wed Mar 7 13:38:28 2018 +0800

    Better logging in iserv-remote


>---------------------------------------------------------------

c5fd54a15c919a4515aefb045271be1042d35772
 libraries/libiserv/src/Remote/Slave.hs | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/libraries/libiserv/src/Remote/Slave.hs b/libraries/libiserv/src/Remote/Slave.hs
index b80d095..9387db1 100644
--- a/libraries/libiserv/src/Remote/Slave.hs
+++ b/libraries/libiserv/src/Remote/Slave.hs
@@ -112,6 +112,7 @@ hook verbose base_path pipe m = case m of
     handleLoad pipe path (base_path <//> path)
     return $ Msg (LoadObj (base_path <//> path))
   Msg (LoadArchive path) -> do
+    when verbose $ putStrLn ("Need Archieve: " ++ path ++ " at " ++ (base_path <//> path))
     handleLoad pipe path (base_path <//> path)
     return $ Msg (LoadArchive (base_path <//> path))
   -- when loading DLLs (.so, .dylib, .dll, ...) and these are provided
@@ -119,7 +120,7 @@ hook verbose base_path pipe m = case m of
   -- therefore we hook the LoadDLL call only for absolute paths to ship the
   -- dll from the host to the target.
   Msg (LoadDLL path) | isAbsolute path -> do
-    when verbose $ putStrLn ("Need DLL: " ++ (base_path <//> path))
+    when verbose $ putStrLn ("Need DLL: " ++ path ++ " at " ++ (base_path <//> path))
     handleLoad pipe path (base_path <//> path)
     return $ Msg (LoadDLL (base_path <//> path))
   _other -> return m


From git at git.haskell.org  Wed Mar  7 05:39:18 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Wed,  7 Mar 2018 05:39:18 +0000 (UTC)
Subject: [commit: ghc] wip/angerman/win32-cross-2: Assume `C:` to be system
 libraries on windows. (d12d240)
Message-ID: <20180307053918.7AA973A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/angerman/win32-cross-2
Link       : http://ghc.haskell.org/trac/ghc/changeset/d12d2409cee20c2fb4d1d3b9f7ae4e63ec7977b9/ghc

>---------------------------------------------------------------

commit d12d2409cee20c2fb4d1d3b9f7ae4e63ec7977b9
Author: Moritz Angermann <moritz.angermann at gmail.com>
Date:   Wed Mar 7 13:38:44 2018 +0800

    Assume `C:` to be system libraries on windows.


>---------------------------------------------------------------

d12d2409cee20c2fb4d1d3b9f7ae4e63ec7977b9
 libraries/libiserv/src/Remote/Slave.hs | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/libraries/libiserv/src/Remote/Slave.hs b/libraries/libiserv/src/Remote/Slave.hs
index 9387db1..701e7d2 100644
--- a/libraries/libiserv/src/Remote/Slave.hs
+++ b/libraries/libiserv/src/Remote/Slave.hs
@@ -119,6 +119,9 @@ hook verbose base_path pipe m = case m of
   -- as relative paths, the intention is to load a pre-existing system library,
   -- therefore we hook the LoadDLL call only for absolute paths to ship the
   -- dll from the host to the target.
+  Msg (LoadDLL path@('C':':':_)) -> do
+    when verbose $ putStrLn ("Need DLL: " ++ path)
+    return $ Msg (LoadDLL path)
   Msg (LoadDLL path) | isAbsolute path -> do
     when verbose $ putStrLn ("Need DLL: " ++ path ++ " at " ++ (base_path <//> path))
     handleLoad pipe path (base_path <//> path)


From git at git.haskell.org  Wed Mar  7 09:14:41 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Wed,  7 Mar 2018 09:14:41 +0000 (UTC)
Subject: [commit: ghc] master: Add perf test for #14052 (40c4313)
Message-ID: <20180307091441.5ED573A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/40c4313a8729cbd0873c16ae69434919343b551f/ghc

>---------------------------------------------------------------

commit 40c4313a8729cbd0873c16ae69434919343b551f
Author: Ömer Sinan Ağacan <omeragacan at gmail.com>
Date:   Wed Mar 7 11:52:05 2018 +0300

    Add perf test for #14052


>---------------------------------------------------------------

40c4313a8729cbd0873c16ae69434919343b551f
 testsuite/tests/perf/should_run/T14052.hs     |    4 +
 testsuite/tests/perf/should_run/T14052.script | 2501 +++++++++++++++++++++++++
 testsuite/tests/perf/should_run/T14052.stdout | 1000 ++++++++++
 testsuite/tests/perf/should_run/all.T         |    7 +
 4 files changed, 3512 insertions(+)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc 40c4313a8729cbd0873c16ae69434919343b551f

From git at git.haskell.org  Wed Mar  7 10:01:58 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Wed,  7 Mar 2018 10:01:58 +0000 (UTC)
Subject: [commit: ghc] master: Add bindist-list.uniq to .gitignore (b120e64)
Message-ID: <20180307100158.A15BC3A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/b120e649b7b13ee2a2c1bfe568a91bea9d271fba/ghc

>---------------------------------------------------------------

commit b120e649b7b13ee2a2c1bfe568a91bea9d271fba
Author: Ömer Sinan Ağacan <omeragacan at gmail.com>
Date:   Wed Mar 7 13:01:20 2018 +0300

    Add bindist-list.uniq to .gitignore


>---------------------------------------------------------------

b120e649b7b13ee2a2c1bfe568a91bea9d271fba
 .gitignore | 1 +
 1 file changed, 1 insertion(+)

diff --git a/.gitignore b/.gitignore
index 460cb68..efc7a89 100644
--- a/.gitignore
+++ b/.gitignore
@@ -88,6 +88,7 @@ _darcs/
 # specific generated files
 
 /bindist-list
+/bindist-list.uniq
 /bindistprep/
 /bindisttest/HelloWorld
 /bindisttest/


From git at git.haskell.org  Wed Mar  7 11:36:08 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Wed,  7 Mar 2018 11:36:08 +0000 (UTC)
Subject: [commit: ghc] master: Schedule.c: remove unreachable code block
 (d9d4632)
Message-ID: <20180307113608.C1E5C3A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/d9d463289fe20316cff12a8f0dbf414db678fa72/ghc

>---------------------------------------------------------------

commit d9d463289fe20316cff12a8f0dbf414db678fa72
Author: Ömer Sinan Ağacan <omeragacan at gmail.com>
Date:   Wed Mar 7 14:34:46 2018 +0300

    Schedule.c: remove unreachable code block


>---------------------------------------------------------------

d9d463289fe20316cff12a8f0dbf414db678fa72
 rts/Schedule.c |  7 -------
 rts/Sparks.c   | 15 ---------------
 2 files changed, 22 deletions(-)

diff --git a/rts/Schedule.c b/rts/Schedule.c
index 885e737..5160cb4 100644
--- a/rts/Schedule.c
+++ b/rts/Schedule.c
@@ -1918,13 +1918,6 @@ delete_threads_and_gc:
             throwToSelf(cap, main_thread, heapOverflow_closure);
         }
     }
-#if defined(SPARKBALANCE)
-    /* JB
-       Once we are all together... this would be the place to balance all
-       spark pools. No concurrent stealing or adding of new sparks can
-       occur. Should be defined in Sparks.c. */
-    balanceSparkPoolsCaps(n_capabilities, capabilities);
-#endif
 
 #if defined(THREADED_RTS)
     stgFree(idle_cap);
diff --git a/rts/Sparks.c b/rts/Sparks.c
index a31a5df..bd5e120 100644
--- a/rts/Sparks.c
+++ b/rts/Sparks.c
@@ -284,21 +284,6 @@ traverseSparkQueue (evac_fn evac, void *user, Capability *cap)
                sparkPoolSize(pool), pool->bottom, pool->top);
 }
 
-/* ----------------------------------------------------------------------------
- * balanceSparkPoolsCaps: takes an array of capabilities (usually: all
- * capabilities) and its size. Accesses all spark pools and equally
- * distributes the sparks among them.
- *
- * Could be called after GC, before Cap. release, from scheduler.
- * -------------------------------------------------------------------------- */
-void balanceSparkPoolsCaps(uint32_t n_caps, Capability caps[])
-   GNUC3_ATTRIBUTE(__noreturn__);
-
-void balanceSparkPoolsCaps(uint32_t n_caps STG_UNUSED,
-                           Capability caps[] STG_UNUSED) {
-  barf("not implemented");
-}
-
 #else
 
 StgInt


From git at git.haskell.org  Wed Mar  7 16:33:44 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Wed,  7 Mar 2018 16:33:44 +0000 (UTC)
Subject: [commit: ghc] tag 'ghc-8.4.1-release' created
Message-ID: <20180307163344.3D9D63A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

New tag    : ghc-8.4.1-release
Referencing: f9817b5d8995bd5425e6d115962f6365c15880b2

From git at git.haskell.org  Thu Mar  8 01:51:55 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Thu,  8 Mar 2018 01:51:55 +0000 (UTC)
Subject: [commit: ghc] master: Use docker images with non-root user (648cb28)
Message-ID: <20180308015155.CE1033A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/648cb28f51593658176f83e8417a5b1f921f9df6/ghc

>---------------------------------------------------------------

commit 648cb28f51593658176f83e8417a5b1f921f9df6
Author: mrkkrp <markkarpov92 at gmail.com>
Date:   Wed Feb 28 16:33:59 2018 +0700

    Use docker images with non-root user
    
    That image creates an unprivileged user to run the test suite under.


>---------------------------------------------------------------

648cb28f51593658176f83e8417a5b1f921f9df6
 .circleci/config.yml                     | 31 ++++++-------------------------
 .circleci/images/x86_64-linux/Dockerfile | 15 ++++++++++++++-
 .circleci/prepare-system.sh              | 12 +++++++-----
 3 files changed, 27 insertions(+), 31 deletions(-)

diff --git a/.circleci/config.yml b/.circleci/config.yml
index 295d803..b4a9947 100644
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -3,16 +3,6 @@ version: 2
 aliases:
   - &defaults
     working_directory: ~/ghc
-
-  # Make sure we have proper openssh before checkout: CircleCI git
-  # does not check the repository out properly without it and also
-  # takes 20 times longer than it should be.
-  - &precheckout
-    run:
-      name: Install OpenSSH client
-      command: |
-        apt-get update -qq
-        apt-get install -qy openssh-client
   - &prepare
     run:
       name: prepare-system
@@ -92,11 +82,10 @@ jobs:
   "validate-x86_64-linux":
     resource_class: xlarge
     docker:
-      - image: haskell:8.2
+      - image: mrkkrp/ghcci-x86_64-linux:0.0.4
     environment:
       <<: *buildenv
     steps:
-      - *precheckout
       - checkout
       - *prepare
       - *submodules
@@ -111,12 +100,11 @@ jobs:
   "validate-x86_64-freebsd":
     resource_class: xlarge
     docker:
-      - image: tweag/toolchain-x86_64-freebsd
+      - image: mrkkrp/ghcci-x86_64-freebsd
     environment:
       TARGET: FreeBSD
       <<: *buildenv
     steps:
-      - *precheckout
       - checkout
       - *prepare
       - *submodules
@@ -152,11 +140,10 @@ jobs:
   "validate-hadrian-x86_64-linux":
     resource_class: xlarge
     docker:
-      - image: haskell:8.2
+      - image: mrkkrp/ghcci-x86_64-linux:0.0.4
     environment:
       <<: *buildenv
     steps:
-      - *precheckout
       - checkout
       - *prepare
       - *submodules
@@ -167,11 +154,10 @@ jobs:
   "validate-x86_64-linux-unreg":
     resource_class: xlarge
     docker:
-      - image: haskell:8.2
+      - image: mrkkrp/ghcci-x86_64-linux:0.0.4
     environment:
       <<: *buildenv
     steps:
-      - *precheckout
       - checkout
       - *prepare
       - *submodules
@@ -183,7 +169,7 @@ jobs:
   "validate-x86_64-linux-llvm":
     resource_class: xlarge
     docker:
-      - image: haskell:8.2
+      - image: mrkkrp/ghcci-x86_64-linux:0.0.4
     environment:
       <<: *buildenv
       BUILD_FLAVOUR: perf-llvm
@@ -191,15 +177,11 @@ jobs:
       - run:
           name: Install LLVM
           command: |
-            apt-get update
-            apt-get install -y curl xz-utils
             curl http://releases.llvm.org/5.0.0/clang+llvm-5.0.0-x86_64-linux-gnu-debian8.tar.xz | tar -xJC ..
-            # See https://discuss.circleci.com/t/how-to-add-a-path-to-path-in-circle-2-0/11554/3
             echo "export PATH=`pwd`/../clang+llvm-5.0.0-x86_64-linux-gnu-debian8/bin:\$PATH" >> $BASH_ENV
       - run:
           name: Verify that llc works
           command: llc
-      - *precheckout
       - checkout
       - *prepare
       - *submodules
@@ -212,12 +194,11 @@ jobs:
   "validate-x86_64-linux-debug":
     resource_class: xlarge
     docker:
-      - image: haskell:8.2
+      - image: mrkkrp/ghcci-x86_64-linux:0.0.4
     environment:
       BUILD_FLAVOUR: devel2
       <<: *buildenv
     steps:
-      - *precheckout
       - checkout
       - *prepare
       - *submodules
diff --git a/.circleci/images/x86_64-linux/Dockerfile b/.circleci/images/x86_64-linux/Dockerfile
index aa8813f..d20f5ba 100644
--- a/.circleci/images/x86_64-linux/Dockerfile
+++ b/.circleci/images/x86_64-linux/Dockerfile
@@ -1,3 +1,16 @@
 FROM haskell:8.2
-RUN adduser ghc --gecos 'GHC builds' --disabled-password
+
+# Make sure we have proper openssh before checkout: CircleCI git
+# does not check the repository out properly without it and also
+# takes 20 times longer than it should be.
+RUN apt-get update -qq
+RUN apt-get install -qy git make automake autoconf gcc perl python3 texinfo xz-utils lbzip2 patch openssh-client sudo -qq curl
+
+# Create a normal user.
+RUN adduser ghc --gecos "GHC builds" --disabled-password
+RUN echo "ghc ALL = NOPASSWD : ALL" > /etc/sudoers.d/ghc
 USER ghc
+
+WORKDIR /home/ghc/
+
+CMD ["bash"]
diff --git a/.circleci/prepare-system.sh b/.circleci/prepare-system.sh
index 193fac9..61396c8 100755
--- a/.circleci/prepare-system.sh
+++ b/.circleci/prepare-system.sh
@@ -42,23 +42,25 @@ case "$(uname)" in
         fail "TARGET=$target not supported"
       fi
     else
-      # assuming Ubuntu
-      apt-get install -qy git make automake autoconf gcc perl python3 texinfo xz-utils lbzip2 patch
       cabal update
-      cabal install --reinstall hscolour --index-state=$hackage_index_state
+      cabal install --reinstall hscolour
+      sudo ln -s /home/ghc/.cabal/bin/HsColour /usr/local/bin/HsColour || true
     fi
     ;;
   Darwin)
     if [[ -n ${TARGET:-} ]]; then
       fail "uname=$(uname) not supported for cross-compilation"
     fi
-    brew install ghc cabal-install python3 ncurses gmp
+    # It looks like we already have python2 here and just installing python3
+    # does not work.
+    brew upgrade python
+    brew install ghc cabal-install ncurses gmp
     cabal update
     cabal install --reinstall alex happy haddock hscolour --index-state=$hackage_index_state
     # put them on the $PATH, don't fail if already installed
     ln -s $HOME/.cabal/bin/alex /usr/local/bin/alex || true
     ln -s $HOME/.cabal/bin/happy /usr/local/bin/happy || true
-    ln -s $HOME/.cabal/bin/hscolour /usr/local/bin/hscolour || true
+    ln -s $HOME/.cabal/bin/HsColour /usr/local/bin/HsColour || true
     ;;
   *)
     fail "uname=$(uname) not supported"


From git at git.haskell.org  Thu Mar  8 01:52:11 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Thu,  8 Mar 2018 01:52:11 +0000 (UTC)
Subject: [commit: ghc] master: Fix a typo about pattern synonyms in
 documentation. (b320ba8)
Message-ID: <20180308015211.9812E3A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/b320ba82e8ae3784d2c509e6a8aae4f4d03ef210/ghc

>---------------------------------------------------------------

commit b320ba82e8ae3784d2c509e6a8aae4f4d03ef210
Author: HE, Tao <sighingnow at gmail.com>
Date:   Mon Mar 5 23:52:29 2018 +0800

    Fix a typo about pattern synonyms in documentation.


>---------------------------------------------------------------

b320ba82e8ae3784d2c509e6a8aae4f4d03ef210
 docs/users_guide/glasgow_exts.rst | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/docs/users_guide/glasgow_exts.rst b/docs/users_guide/glasgow_exts.rst
index 40013f3..5bcd67e 100644
--- a/docs/users_guide/glasgow_exts.rst
+++ b/docs/users_guide/glasgow_exts.rst
@@ -5155,7 +5155,7 @@ Pattern synonyms
 
 Pattern synonyms are enabled by the language extension :extension:`PatternSynonyms`, which is
 required for defining them, but *not* for using them. More information and
-examples of view patterns can be found on the `Wiki page <PatternSynonyms>`.
+examples of pattern synonyms can be found on the :ghc-wiki:`Wiki page <PatternSynonyms>`.
 
 Pattern synonyms enable giving names to parametrized pattern schemes.
 They can also be thought of as abstract constructors that don't have a


From git at git.haskell.org  Thu Mar  8 01:52:25 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Thu,  8 Mar 2018 01:52:25 +0000 (UTC)
Subject: [commit: ghc] master: Users Guide: Add that --numa is available on
 Windows too (b3bfbed)
Message-ID: <20180308015225.4A8173A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/b3bfbedc106a50eacc635f8ec7ad130ce6e43617/ghc

>---------------------------------------------------------------

commit b3bfbedc106a50eacc635f8ec7ad130ce6e43617
Author: Simon Jakobi <simon.jakobi at gmail.com>
Date:   Mon Mar 5 06:19:20 2018 +0100

    Users Guide: Add that --numa is available on Windows too
    
    Windows support was added in c93813d96b1da53a2ebd9c9ac5af6cc3e3443c43


>---------------------------------------------------------------

b3bfbedc106a50eacc635f8ec7ad130ce6e43617
 docs/users_guide/runtime_control.rst | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/docs/users_guide/runtime_control.rst b/docs/users_guide/runtime_control.rst
index f8e0ce0..009e3ae 100644
--- a/docs/users_guide/runtime_control.rst
+++ b/docs/users_guide/runtime_control.rst
@@ -685,7 +685,7 @@ performance.
        single: NUMA, enabling in the runtime
 
     Enable NUMA-aware memory allocation in the runtime (only available
-    with ``-threaded``, and only on Linux currently).
+    with ``-threaded``, and only on Linux and Windows currently).
 
     Background: some systems have a Non-Uniform Memory Architecture,
     whereby main memory is split into banks which are "local" to


From git at git.haskell.org  Thu Mar  8 01:52:38 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Thu,  8 Mar 2018 01:52:38 +0000 (UTC)
Subject: [commit: ghc] master: Fix typo in description of -V RTS flag (43fbb90)
Message-ID: <20180308015238.C3D003A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/43fbb905eade2e3e3af67ce944262709763b6578/ghc

>---------------------------------------------------------------

commit 43fbb905eade2e3e3af67ce944262709763b6578
Author: Tej Chajed <tchajed at mit.edu>
Date:   Tue Mar 6 13:46:01 2018 -0500

    Fix typo in description of -V RTS flag


>---------------------------------------------------------------

43fbb905eade2e3e3af67ce944262709763b6578
 rts/RtsFlags.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/rts/RtsFlags.c b/rts/RtsFlags.c
index eb33c9e..7b38bbd 100644
--- a/rts/RtsFlags.c
+++ b/rts/RtsFlags.c
@@ -377,7 +377,7 @@ usage_text[] = {
 "            Default: 0.02 sec.",
 "  -V<secs>  Master tick interval in seconds (0 == disable timer).",
 "            This sets the resolution for -C and the heap profile timer -i,",
-"            and is the frequence of time profile samples.",
+"            and is the frequency of time profile samples.",
 #if defined(PROFILING)
 "            Default: 0.001 sec.",
 #else


From git at git.haskell.org  Thu Mar  8 03:58:21 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Thu,  8 Mar 2018 03:58:21 +0000 (UTC)
Subject: [commit: ghc] wip/kavon-nosplit-llvm: Merge branch 'master' into
 wip/kavon-nosplit-llvm (4a6eb16)
Message-ID: <20180308035821.960CD3A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/kavon-nosplit-llvm
Link       : http://ghc.haskell.org/trac/ghc/changeset/4a6eb165ba46f3447d44f1550c9e5e2e2d4bc421/ghc

>---------------------------------------------------------------

commit 4a6eb165ba46f3447d44f1550c9e5e2e2d4bc421
Merge: 5eae140 d9d4632
Author: Kavon Farvardin <kavon at farvard.in>
Date:   Wed Mar 7 18:17:21 2018 -0600

    Merge branch 'master' into wip/kavon-nosplit-llvm
    
    Resolved Conflicts in:
    	compiler/cmm/CmmCommonBlockElim.hs
    
    Merged up to: d9d463289fe20316cff12a8f0dbf414db678fa72



>---------------------------------------------------------------


Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc 4a6eb165ba46f3447d44f1550c9e5e2e2d4bc421

From git at git.haskell.org  Thu Mar  8 03:58:24 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Thu,  8 Mar 2018 03:58:24 +0000 (UTC)
Subject: [commit: ghc] wip/kavon-nosplit-llvm: fix build due to the removal of
 Hoopl.Unique (54321d5)
Message-ID: <20180308035824.617993A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/kavon-nosplit-llvm
Link       : http://ghc.haskell.org/trac/ghc/changeset/54321d57aa315046b7690d1d6aa9cf08750f1ef3/ghc

>---------------------------------------------------------------

commit 54321d57aa315046b7690d1d6aa9cf08750f1ef3
Author: Kavon Farvardin <kavon at farvard.in>
Date:   Wed Mar 7 20:27:43 2018 -0600

    fix build due to the removal of Hoopl.Unique


>---------------------------------------------------------------

54321d57aa315046b7690d1d6aa9cf08750f1ef3
 compiler/llvmGen/LlvmMangler.hs | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/compiler/llvmGen/LlvmMangler.hs b/compiler/llvmGen/LlvmMangler.hs
index e905fe0..4d2d461 100644
--- a/compiler/llvmGen/LlvmMangler.hs
+++ b/compiler/llvmGen/LlvmMangler.hs
@@ -23,7 +23,6 @@ import qualified Data.ByteString.Char8 as B
 import System.IO
 import Hoopl.Label
 import Hoopl.Collections
-import Hoopl.Unique ( intToUnique )
 import Data.Maybe ( fromMaybe )
 
 -- note [mangler string func]
@@ -85,7 +84,7 @@ addInfoTable :: LabelMap ManglerStr -> LabRewrite
 addInfoTable info FirstLabel dflags line = do
         retPt <- stripPrefix labPrefix line
         (i, _) <- B.readInt retPt
-        statics <- mapLookup (toKey i) info
+        statics <- mapLookup (mkHooplLabel i) info
         fullName <- stripSuffix colon line
         return $ B.concat $ (map (\f -> f fullName) statics) ++ [line]
     where
@@ -99,7 +98,6 @@ addInfoTable info FirstLabel dflags line = do
                         otherwise -> panic "Please update LLVM Mangler for this OS."
                         
         colon = B.pack ":"
-        toKey = uniqueToLbl . intToUnique
         
         -- TODO(kavon): on Travis CI, it seems the bytestring package is out of date, and
         -- we're missing B.stripSuffix and B.stripPrefix. I've reimplemented them here.


From git at git.haskell.org  Thu Mar  8 03:58:29 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Thu,  8 Mar 2018 03:58:29 +0000 (UTC)
Subject: [commit: ghc] wip/kavon-nosplit-llvm's head updated: fix build due to
 the removal of Hoopl.Unique (54321d5)
Message-ID: <20180308035829.423983A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

Branch 'wip/kavon-nosplit-llvm' now includes:

     d8d87fa Remove m_type from Match (#14313)
     429fafb Add regression test for #14326
     f6bca0c Testsuite update following d8d87fa
     341d3a7 Incorporate changes from #11721 into Template Haskell
     f1d2db6 Fix #14320 by looking through HsParTy in more places
     f337a20 Simply Data instance context for AmbiguousFieldOcc
     e51e565 Split SysTools up some
     7720c29 Tidy up some convoluted "child/parent" code
     ab1a7583 Typos in comments only
     461c831 Minor refactoring
     c81f66c Fix over-eager error suppression in TcErrors
     79ae03a Change "cobox" to "co" in debug output
     3e44562 Delete two unused functions
     f20cf98 Remove wc_insol from WantedConstraints
     9c3f731 Fix #10816 by renaming FixitySigs more consistently
     6869864 Pretty-printing of derived multi-parameter classes omits parentheses
     4bb54a4 Avoid creating dependent types in FloatOut
     13fdca3 Add a missing zonk in TcDerivInfer.simplifyDeriv
     82b77ec Do not quantify over deriving clauses
     15aefb4 Add missing T14325.stderr
     fb050a3 Do not bind coercion variables in SpecConstr rules
     3de788c Re-apply "Typeable: Allow App to match arrow types"
     2be55b8 Delete obsolete docs on GADT interacton with TypeApplications
     4a677f7 Remove section about ApplicativeDo & existentials (#13875)
     8adb84f Fix calculation in threadStackOverflow
     afac6b1 Fix typo
     6aa6a86 Fix typo
     add85cc Fix panic for `ByteArray#` arguments in CApiFFI foreign imports
     e3ba26f Implement new `compareByteArrays#` primop
     5984a69 Override default `clearBit` method impl for `Natural`
     843772b Enable testing 'Natural' type in TEST=arith011
     6cc232a Implement {set,clear,complement}BitBigNat primitives
     71a4235 configure: Fix CC version check on Apple compilers
     fd8b044 Levity polymorphic Backpack.
     5dab544 FreeBSD dtrace probe support
     7e790b3 rts: Label all threads created by the RTS
     8536b7f users-guide: Rework and finish debug flag documentation
     d7f4f41 users guide: Eliminate redundant :category: tags in debugging.rst
     c5da84d users-guide: Fix various warnings
     a69fa54 rts/posix: Ensure that memory commit succeeds
     d6c33da RtClosureInspect: Fix inspecting Char# on 64-bit big-endian
     366182a ghci: Include "Rts.h" before using TABLES_NEXT_TO_CODE
     9e3add9 Flags.hsc: Peek a CBool (Word8), not a Bool (Int32)
     aa98268 updateThunk: indirectee can be tagged
     21b7057 users-guide: Clarify -ddump-asm-regalloc-stages documentation
     6cb4642 Bump ghc-prim to 0.5.2.0 and update changelog
     ed48d13 Simplify, no functionality change
     2f43615 Fix grammaros in comments
     317aa96 Improve user’s guide around deriving
     74cd1be Don't deeply expand insolubles
     5a66d57 Better solving for representational equalities
     aba7786 Typofix in comment
     870020e whitespace only
     20ae22b Accept test output for #14350
     e023e78 Disable -XRebindableSyntax when running internal GHCi expressions
     101a8c7 Error when deriving instances in hs-boot files
     8846a7f Fix #14369 by making injectivity warnings finer-grained
     de8752e Export injectiveVarsOf{Binder,Type} from TyCoRep
     7ac22b7 User's guide: Fix the category of some flags
     3befc1a Bump arcanist-external-json-linter submodule
     1ba2851 Expose monotonic time from GHC.Event.Clock
     13758c6 Added a test for 'timeout' to be accurate.
     098dc97 Give a reference to Foreign.Concurrent.
     b6204f7 Untag the potential AP_STACK in stg_getApStackValzh
     2ca8cf6 Add Functor Bag instance
     afc04b2 Outputable: Add pprTraceException
     c1efc6e Comments and white space
     3acd616 Improve kick-out in the constraint solver
     e375bd3 Update record-wildcard docs
     99c61e2 Add stack traces on crashes on Windows
     bb537b2 nofib submodule: Fix a problem with fasta-c.c
     1e24a24 submodule nofib: Add digits-of-e1.faststdout
     052ec24 submodule nofib: Add digits-of-e2.faststdout
     b10a768 Comments only
     d1eaead Temporary fix to Trac #14380
     671b1ed User’s guide: Properly link to RTS flag -V
     8843a39 Include usg_file_hash in ghc --show-iface output
     3825b7e Remove the 'legroom' part of the timeout-accurate-pure test.
     b62097d Windows: Bump to GCC 7.2 for GHC 8.4
     e888a1f Revert "Windows: Bump to GCC 7.2 for GHC 8.4"
     561bdca Update Win32 version for GHC 8.4.
     f744261 ghc-cabal: Inline removed function from Cabal.
     2e16a57 Revert "ghc-cabal: Inline removed function ..."
     b1ad0bb Revert "Update Win32 version for GHC 8.4."
     61f1b46 Make language extensions their own category in the documentation
     bf83435 typecheck: Clarify errors mentioned in #14385
     bd53b48 Add info about Github pull requests.
     2a4c24e Make layLeft and reduceDoc stricter (#7258)
     980e127 Windows: Update the mirror script to generate hashes and use mirror fallback
     1c15d8e Fix space leak in BinIface.getSymbolTable
     df63668 Performance improvements linear regAlloc (#7258)
     f7f270e Implement `-Wpartial-fields` warning (#7169)
     821adee Fix a bug in 'alexInputPrevChar'
     2c23fff user-guide: Clarify default optimization flags
     4c06ccb base: Enable listToMaybe to fuse via foldr/build
     dbd81f7 Factor out readField (#14364)
     d91a6b6 Declare upstram repo location for hsc2hs
     160a491 users-guide: Disable index node generation
     9ae24bb configure: Add Alpine Linux to checkVendor
     a10c2e6 Don't use $SHELL in wrapper scripts
     355318c Add more pprTrace to SpecConstr (debug only)
     7d7d94f Fix an exponential-blowup case in SpecConstr
     41f9055 ApplicativeDo: handle BodyStmt (#12143)
     acd355a relnotes: Fix a few minor formatting issues
     faf60e8 Make tagForCon non-linear
     922db3d Manual: The -ddump-cmm-* flags had a wrong spelling in the manual
     97ca0d2 simplNonRecJoinPoint: Handle Shadowing correctly
     0e953da Implement a dedicated exitfication pass #14152
     3b784d4 base: Implement file locking in terms of POSIX locks
     cecd2f2 Add -falignment-sanitization flag
     7673561 Turn `compareByteArrays#` out-of-line primop into inline primop
     85aa1f4 Fix #14390 by making toIfaceTyCon aware of equality
     cca2d6b Allow packing constructor fields
     82bad1a A bit more tc-tracing
     1b115b1 Fix typo in accessor name
     ec356e8 Typofix in panic
     1569668 Typofixes in comments
     53700a9 minor wordsmithing
     201b5aa Catch a few more typos in comments
     609f284 Add Note [Setting the right in-scope set]
     af0aea9 core-spec: Add join points to formalism
     29ae833 Tidy up IfaceEqualityTyCon
     1317ba6 Implement the EmptyDataDeriving proposal
     1130c67 PPC NCG: Impl branch prediction, atomic ops.
     b0b80e9 Implement the basics of hex floating point literals
     e0df569 Use proper Unique for Name
     b938576 Add custom exception for fixIO
     36f0cb7 TcRnDriver: Bracket family instance consistency output in -ddump-rn-trace
     cbd6a4d Introduce -dsuppress-stg-free-vars flag
     bd765f4 Fix atomicread/write operations
     d9b6015 Revert "Move check-ppr and check-api-annotations to testsuite/utils"
     51321cf rts/PrimOps.cmm: add declaration for heapOverflow closure
     4353756 CmmSink: Use a IntSet instead of a list
     15f788f llvmGen: Pass vector arguments in vector registers by default
     eb37132 Bump haddock submodule
     3c8e55c Name TypeRep constructor fields
     19ca2ca Deserialize all function TypeReps
     5d48f7c Fix documentation and comment issues
     df479f7 change example from msum to mfilter
     436b3ef Clean up comments about match algorithm a bit.
     f6521e6 testsuite: Bump metrics of haddock.Cabal
     4dfb790 rts/win32: Emit exception handler output to stderr
     6f990c5 cmm/CBE: Fix comparison between blocks of different lengths
     a27056f cmm/CBE: Fix a few more zip uses
     2ded536 Typo in glasgow_exts.rst
     35642f4 Update ErrorCall documentation for the location argument
     8613e61 DynFlags: Introduce -show-mods-loaded flag
     59de290 Update autoconf test for gcc to require 4.7 and up
     66b5b3e Specialise lcm :: Word -> Word -> Word (trac#14424)
     275ac8e base: Add examples to Bifunctor documentation
     7b0b9f6 Squashed 'hadrian/' content from commit 438dc57
     5cee480 Merge commit '7b0b9f603bb1215e2b7af23c2404d637b95a4988' as 'hadrian'
     0ff152c WIP on combining Step 1 and 3 of Trees That Grow
     7d6fa32 Set up Linux, OSX and FreeBSD on CircleCI.
     b0cabc9 Set up AppVeyor, Windows CI.
     6f665cc Sdist -> bindist -> tests
     07e0d0d Revert "Sdist -> bindist -> tests"
     ed18f47 Factor out builds into steps. Address ghc/ghc#83 comments.
     ae7c33f testsuite: Bump haddock.compiler allocations
     7d34f69 relnotes: Clarify a few things
     c1bc923 relnotes: Note enabling of -fllvm-pass-vectorse-in-regs
     93b4820 Revert "WIP on combining Step 1 and 3 of Trees That Grow"
     9f8dde0 Update link to Haskeline user preferences
     bf9ba7b base: Escape \ in CallStack example
     14d885e Merge remote-tracking branch 'github/pr/83'
     21970de Imrpove comments about equality types
     30058b0 Fix another dark corner in the shortcut solver
     2c2f3ce Minimise provided dictionaries in pattern synonyms
     fe6848f Fix in-scope set in simplifier
     438dd1c WIP on Doing a combined Step 1 and 3 for Trees That Grow
     803ed03 Invoke lintUnfolding only on top-level unfoldings (#14430)
     6bd352a Remove left-overs from compareByteArray# inline conversion
     10ff3e3 testsuite: Fix output of T14394
     bdd2d28 Update Win32 version for GHC 8.4.
     9773053 Merge initial Hadrian snapshot
     ce9a677 base: Add test for #14425
     c59d6da base: Normalize style of approxRational
     5834da4 base: Fix #14425
     0656cb4 Update comment in GHC.Real (trac#14432)
     6b52b4c Remove unreliable Core Lint empty case checks
     e6b13c9 testsuite: Add test for #5889
     75291ab Change `OPTIONS_GHC -O` to `OPTIONS_GHC -O2`
     f8e7fec Fix PPC NCG after blockID patch
     5229c43 Squashed 'hadrian/' changes from 438dc576e7..5ebb69ae1e
     506ba62 Merge commit '5229c43ccf77bcbffeced01dccb27398d017fa34'
     f11f252 Windows: Bump to GCC 7.2 for GHC 8.4
     ba2ae2c Adds cmm-sources to base
     426af53 Use LICENSE instead of ../LICENSE in the compiler.cabal file
     5f158bc circleci: Bump down thread count
     86c50a1 Declare proper spec version in `base.cabal`
     e3ec2e7 WIP on combined Step 1 and 3 for Trees That Grow, HsExpr
     0a85190 Fix a TyVar bug in the flattener
     f570000 A bit more tc-tracing
     47ad657 TTG3 Combined Step 1 and 3 for Trees That Grow
     f5dc8cc Add new mbmi and mbmi2 compiler flags
     6dfe982 StaticPointers: Clarify documentation
     5dea62f Adds rts/rts.cabal.in file
     8b1020e RTS: Disable warnings in ffi.h
     ea26162 CLabel: Clean up unused label types
     1aba27a CLabels: Remove CaseLabel
     383016b Add dump flag for timing output
     d9f0c24 rts: Fix gc timing
     d0a641a Allow the rts lib to be called rts-1.0
     3bed4aa Cabalify all the things
     e14945c Adjust AltCon Ord instance to match Core linter requirements.
     ec080ea users_guide: Fix "CancelSynchronousIo" casing
     c1fcd9b Squashed 'hadrian/' changes from 5ebb69a..fa3771f
     07ac921 Pull recent Hadrian changes from upstream
     2f46387 Detect overly long GC sync
     2da7813 Document -ddump-timings
     c729734 configure: Fix incorrect quoting
     12a7444 Adds -ghc-version flag to ghc.
     835d8dd GHC.Prim use virtual-modules
     bb11a2d Relocatable GHC
     74070bb Fix rts.cabal.in
     912a72d Fix T4437
     b8e324a base: Make documentation of atomically more accurate
     7d16d8a Fix #elfi -> #elif; unbreak -Werror.
     ca3700a Rename ghc-version -> ghcversion-file
     606bbc3 Stop generating make files when using hadrian.
     e66913d Bump hsc2hs submodule
     25f36bd Bump haddock submodule
     ddded7e ghc-pkg: Add missing newlines to usage message
     1b1ba9d rel-notes: Fix up formatting in release notes
     d213ee8 CircleCI: Disable artifact collection on OS X
     66d1799 configure: Fix ar probed flags
     0b20d9c base: Document GHC.Stack.CCS internals
     314bc31 Revert "trees that grow" work
     90a819b CircleCI: Add webhook for Harbormaster builds
     2ca2259 Update ANNOUNCE
     763ecac rts: Move libdwPrintBacktrace to public interface
     f376eba rts: Fix inconsistencies in how retainer and heap censuses are timed.
     63e4ac3 Add warn-missing-export-lists
     8a8a79a Update leftover reference to refer to [FunBind vs PatBind]
     dad9864 Remove hadrian sub-dir from .gitignore
     0db4627 Test Trac #14488
     bb2a08e testsuite: Add test for #14257
     23116df cmm: Optimise remainders by powers of two
     eb5a40c base: Remove redundant subtraction in (^) and stimes
     7a73a1c Bump stm submodule
     2d1c671 ErrUtils: Refactor dump file logic
     c11f145 ErrUtils: Ensure timing dumps are always output on one line
     360d740 Squashed 'hadrian/' changes from fa3771fe6b..4499b294e4
     abdb555 Update Hadrian
     341013e Revert "Add new mbmi and mbmi2 compiler flags"
     5fdb858 Fix README
     33cbc9f CircleCI: Perform nightly validation of unregisterised build
     866f669 CircleCI: Try validating LLVM as well
     e2cc106 circleci: Build with Hadrian
     ad57e28 CircleCI: Install lbzip2 and patch
     5e35627 rts/Printer: add closure name entries for small arrays (Fixes #14513)
     30aa643 SysTools: Expand occurrences of $topdir anywhere in a Settings path
     69cd1e9 SysTools: Split up TopDir logic into new module
     599243e DynFlags: Expand $topdir in --info output
     99089fc users-guide: Fix :default: placement
     f209e66 base: fdReady(): Fix timeouts > ~49 days overflowing. Fixes #14262.
     a1950e6 CircleCI: Reenable artifact collection on Darwin
     471d677 Don't complain about UNPACK in -fno-code.
     6282366 Follow symlinks in the Win32 code for System.Environment.getExecutablePath
     b241d6d Add obvious Outputable Integer instance.
     f713be7 RtsFlags: allow +RTS -K0
     00b96b2 boot: Eliminate superfluous output
     4efe5fe Check quantification for partial type signatues
     df1a0c0 typecheck: Consistently use pretty quotes in error messages
     eb86e86 Don't call alex for Cabal lib during GHC build
     e4dc2cd relnotes: Rework treatment of included package list
     54fda25 base: Rip out old RTS statistics interface
     17e71c1 CLabel.labelType: Make catch-all case explicit
     048a913 cmm: Use LocalBlockLabel instead of AsmTempLabel to represent blocks
     16dd532 CLabel: Refactor pprDynamicLinkerAsmLabel
     55e621c nativeGen: Use plusUFMList instead of foldr
     7dc82d6 nativeGen: Use foldl' instead of foldl
     66c1c8e CLabel: More specific debug output from CLabel
     d3b80c7 Cmm: Add missing cases for BlockInfoTable
     030d9d4 CLabel: A bit of documentation
     4c65867 CircleCI: Disallow hscolour 1.24.3
     3c0ffd1 CircleCI: Freeze all packages at fixed index state
     5b3f33b Minor tweaks to codegens.rst
     b6428af Comments only: Trac #14511
     b6a2691 Bump unix submodule
     f246d35 Darwin: Set deployment target
     d672b7f Darwin: Use gmp from homebrew
     6998772 Make use of boot TyThings during typechecking.
     e1fb283 Handle CPP properly in Backpack
     12efb23 Add trace injection
     bc761ad Cache TypeRep kinds aggressively
     1acb922 Make the Con and Con' patterns produce evidence
     cfea745 template-haskell: Rip out FamFlavour
     595f60f Fix ghc_packages
     d6fccfb Bump version to 8.5
     30d6373 rts: fix filename case for mingw32 target
     1ecbe9c utils/hsc2hs: update submodule
     5f332e1 Forward-port changes from GHC 8.2 branch
     fa29df0 Refactor ConDecl: Trac #14529
     e4a1f03 Revert accidental hsc2hs submodule downgrade
     de20440 Refactor kcHsTyVarBndrs
     800009d Improve LiberateCase
     5695f46 Occurrrence analysis improvements for NOINLINE functions
     7733e44 Rip out hadrian subtree
     4335c07 Add hadrian as a submodule
     716acbb Improved panic message for zonkTcTyVarToTyVar
     8b36ed1 Build only well-kinded types in type checker
     8361b2c Fix SigTvs at the kind level
     abd5db6 Only look for locales of the form LL.VV
     21be5bd Fixed misprint 'aqcuired'
     6847c6b Improve Control.Monad.guard and Control.Monad.MonadPlus docs
     00d7132 Add information about irrefutable pattern Syntax to XStrict.
     21cdfe5 Add NOINLINE pragma to hPutStr'
     4bfff7a rts: Don't default to single capability when profiled
     cafe983 Always use the safe open() call
     708ed9c Allow users to ignore optimization changes
     430d1f6 fdReady: Use C99 bools / CBool in signature
     9d29925 base: fdReady(): Return only after sycall returns after `msecs` have passed
     be1ca0e Add regression test for #14040
     a106a20 Minor refactor of TcExpr.tcApp
     e40db7b Detect levity-polymorphic uses of unsafeCoerce#
     321b420 Tidy up of wired-in names
     aef4dee Add missing stderr for Trac #14561
     63e968a Re-centre perf for T5321Fun
     0a12d92 Further improvements to well-kinded types
     6eb3257 Typofix in comment
     6f6d105 Add test for Trac #14580
     b1ea047 Fix an outright bug in the unflattener
     fa1afcd Better tc-trace messages
     eeb36eb typos in local var
     16c7d9d Fix #14135 by validity checking matches
     d4c8d89 users-guide: Consistently document LLVM version requirement
     4a331e6 users-guide: Fix various bits of markup
     6814945 Fix tcDataKindSig
     3910d3e Add some commentary re: fix to #11203
     23b5b80 Add missing case to HsExpr.isMonadFailStmtContext
     1e64fc8 Tiny refactor: use mkTyVarNamePairs
     f1fe5b4 Fix scoping of pattern-synonym existentials
     fb1f0a4 Blackholes can be large objects (#14497)
     0302439 testsuite: Exit with non-zero exit code when tests fail
     8c9906c testsuite: Semigroup/Monoid compat for T3001-2
     244d144 Typos in comments
     a100763 Get rid of some stuttering in comments and docs
     10ed319 Stop runRW# being magic
     ff1544d Rmove a call to mkStatePrimTy
     71f96bb Sync up ghc-prim changelog from GHC 8.2 branch
     1bd91a7 Fix #14578 by checking isCompoundHsType in more places
     9caf40e Fix #14588 by checking for more bang patterns
     9cb289a Remove hack put in place for #12512
     b6304f8 Document ScopedTypeVariables' interaction with nested foralls
     4d41e92 Improve treatment of sectioned holes
     584cbd4 Simplify HsPatSynDetails
     72938f5 Check for bogus quantified tyvars in partial type sigs
     a492af0 Refactor coercion holes
     f5cf9d1 Fix floating of equalities
     bcb519c Typos in comments
     05551d0 Comments only [skip ci]
     fc257e4 Sync `ghc-prim` changelog from GHC 8.2
     c88564d MkIface: Ensure syntactic compatibility with ghc 8.0.1
     6549706 relnotes: Fix typo in pattern synonym example
     e237e1f Bump Cabal submodule
     d7d0aa3 Add GHC 8.6.1 release notes
     02aaeab aclocal.m4: add minimal support for nios2 architecture
     e19b646 Compute InScopeSet in substInteractiveContext
     722a658 Fix #14618 by applying a subst in deeplyInstantiate
     f2db228 Typos in comments [ci skip]
     862c59e Rewrite Note [The polymorphism rule of join points]
     a2e9549 users-guide: Fix markup
     b31c721 Fix sign error in kelvinToC.
     12f5c00 Prevent "C--" translating to "C–" in the User's Guide.
     69f1e49 Reformat Control.Monad.mfilter docs
     a67c264 Add example to Control.Monad.join docs
     4887c30 Improve Control.Monad docs
     27b7b4d Windows: fix all failing tests.
     46287af Make System.IO.openTempFile thread-safe on Windows
     ecff651 Fix #14608 by restoring an unboxed tuple check
     3382ade Rename HEq_sc and Coercible_sc to heq_sel and coercible_sel
     2c7b183 Comments only
     83b96a4 More informative pretty-printing for phantom coercions
     f3a0fe2 Comments about join point types
     1e12783 Tiny refactor around fillInferResult
     3bf910d Small refactoring in Coercion
     112266c White space only
     9e5535c Fix OptCoercion
     bd438b2 Get evaluated-ness right in the back end
     298ec78 No deferred type errors under a forall
     7a25659 Typos in comments
     649e777 Make typeToLHsType produce kind signatures for tycon applications
     6c34824 Cache the number of data cons in DataTyCon and SumTyCon
     954cbc7 Drop dead Given bindings in setImplicationStatus
     e2998d7 Stop double-stacktrace in ASSERT failures
     86ea3b1 comments only
     307d1df Fix deep, dark corner of pattern synonyms
     c732711 Improve pretty-printing for pattern synonyms
     40cbab9 Fix another obscure pattern-synonym crash
     303106d Make the Div and Mod type families `infixl 7`
     a1a689d Improve accuracy of get/setAllocationCounter
     fb78b0d Export typeNat{Div;Mod;Log}TyCon from TcTypeNats
     30b1fe2 Remove a bogus warning
     66ff794 Fix join-point decision
     1c1e46c preInlineUnconditionally is ok for INLINEABLE
     448685c Small local refactoring
     1577908 Fix two more bugs in partial signatures
     dbdf77d Lift constructor tag allocation out of a loop
     f3f90a0 Fix previous patch
     6c3eafb KQueue: Fix write notification requests being ignored...
     b2f10d8 Fix mistaken merge
     e20046a Support constructor Haddocks in more places
     a770226 Fix regression on i386 due to get/setAllocationCounter change
     d1ac1c3 Rename -frule-check to -drule-check and document
     492e604 Kill off irrefutable pattern errors
     3d17f1f Tweak link order slightly to prefer user shared libs before system ones.
     87917a5 Support LIBRARY_PATH and LD_LIBRARY_PATH in rts
     9f7edb9 Fix hashbang of gen-data-layout
     78306b5 CoreLint: typo in a comment
     2feed11 Fix hash in haddock of ghc-prim.
     41afbb3 Add flag -fno-it
     f380115 Parenthesize forall-type args in cvtTypeKind
     1bf70b2 Remove executable filename check on windows
     bc383f2 Simplify guard in createSwitchPlan.
     8de8930 configure: Various cleanups
     cf2c029 Fix quadratic behavior of prepareAlts
     c65104e Typos in comments
     6b1ff00 Fix references to cminusminus.org
     1e14fd3 Inform hole substitutions of typeclass constraints (fixes  #14273).
     8bb150d Revert "Fix regression on i386 due to get/setAllocationCounter change"
     e1d4140 Revert "Improve accuracy of get/setAllocationCounter"
     3335811 cmm: Include braces on default branch as required by the parser
     2a78cf7 Remove unused extern cost centre collection
     575c009 Fix #14681 and #14682 with precision-aimed parentheses
     5e8ea6a testsuite: Add test for #14335
     f855769 Add new mbmi and mbmi2 compiler flags
     765ba65 testsuite: Add testcase for #14670
     0074a08 Fix #14692 by correcting an off-by-one error in TcGenDeriv
     5edb18a tentative improvement to callstack docs
     180ca65 [rts] Adjust whitehole_spin
     4a13c5b Implement underscores in numeric literals (NumericUnderscores extension)
     8829743 Use IntSet in Dataflow
     6c0db98 SysTools: Add detection support for LLD linker
     2671ccc Update Cabal submodule
     24e56eb Bump transformers submodule to 0.5.5.0
     a3cde5f Improve comments about TcLevel invariants
     452dee3 Pass -dsuppress-uniques when running T14507
     f00ddea Allocate less in plus_mod_dep
     d36ae5d Comments about CoercionHoles
     076bdb3 Remove dead code: mkNthCoRole
     2a2e6a8 Comments only
     0636689 Fix the lone-variable case in callSiteInline
     d6e0338 Bump terminfo submodule
     40c753f testsuite: Bump haddock.Cabal allocations due to submodule bump
     0e022e5 Turn EvTerm (almost) into CoreExpr (#14691)
     983e491 testsuite: Add testcase for #12158
     66961dc Haddock needs to pass visible modules for instance filtering
     302aee5 base: Refactor Show ErrorCall instance into proper ShowS style
     52dfb25 Handle the likely:True case in CmmContFlowOpt
     e7dcc70 Add ability to parse likely flags for ifs in Cmm.
     31c260f Add ptr-eq short-cut to `compareByteArrays#` primitive
     cbdea95 Sort valid substitutions for typed holes by "relevance"
     cacba07 Linker: ignore empty paths in addEnvPaths
     bd58e29 Remove Hoopl.Unique
     9a57cfe Option for LINE pragmas to get lexed into tokens
     a55d581 Fix Windows stack allocations.
     59fa7b3 Fix #14719 by using the setting the right SrcSpan
     7ff6023 cmm: Use two equality checks for two alt switch with default
     1cb12ea Bump hadrian submodule
     96d2eb2 Invert likeliness when improving conditionals
     1205629 Add likely annotation to cmm files in a few obvious places.
     5e8d314 Update outputs of T12962, scc003
     47031db A bit more tc-tracing
     e7c3878 Move zonkWC to the right place in simplfyInfer
     0f43d0d More tc-tracing
     efba054 Prioritise equalities when solving, incl deriveds
     e9ae0ca Look inside implications in simplifyRule
     55aea8f testsuite: Mark scc001 and T5363 as broken due to #14705
     370b167 circleci: Add Dockerfile for x86_64-linux
     b37dc23 appveyor: Don't install gcc
     fe6fdf6 testsuite: Fix test output of T14715
     7d9812e testsuite: Fix test output broken by efba054640d3
     5f922fb appveyor: Refactor
     0171e09 Make RTS keep less memory (fixes #14702)
     0bff9e6 Don't add targets that can't be found in GHCi
     be84823 Implement BlockArguments (#10843)
     1a911f2 Sequester deriving-related validity check into cond_stdOK
     382c12d rts: Ensure that forkOS releases Task on termination
     add4e1f Mark xmm6 as caller saved in the register allocator for windows.
     e4ab65b Optimize coercionKind (Trac #11735)
     ced9fbd UnboxedTuples can't be used as constraints
     618a805 Experiment with eliminating the younger tyvar
     db5a4b8 Re-center improved perf for T3064
     efce943 Add -ddump-ds-preopt
     e31b41b Flag `-fdefer-typed-holes` also implies `-fdefer-out-of-scope-variables`.
     2974b2b Hoopl.Collections: change right folds to strict left folds
     c3ccd83 testsuite: Fix scc001 profile output
     7fb3287 Add HasDebugCallStack to nameModule
     4f52bc1 DriverPhases: Fix flipped input extensions for cmm and cmmcpp
     3441b14 integer-gmp: Simplify gmp/configure invocation
     fdf518c Upgrade containers submodule
     217e417 ghc-prim: Emulate C11 atomics when not available
     d8a0e6d Don't apply dataToTag's caseRules for data families
     e5d0101 base: Deprecate STM invariant checking primitives
     50adbd7 cmm: Revert more aggressive CBE due to #14226
     606edbf testsuite: Add testcase for #14754
     d987f71 Improve unboxed sum documentation
     326df5d Bump Cabal submodule
     d2511e3 Compute the union of imp_finsts on the side
     7ad72eb cmm: Remove unnecessary HsVersion.h includes
     1512b63 rts: Fix format of failed memory commit message
     4d1c3b7 rts: Add format attribute to barf
     4c36440 Restore 'It is a member of hidden package' message.
     2987b04 Improve X86CodeGen's pprASCII.
     3cd1305 rts: Use BITS_IN macro in bitmap calculations
     00f1a4a rts: fix some barf format specifiers.
     da46813 testsuite: Add test for #14768
     4aa98f4 Fix utterly bogus TagToEnum rule in caseRules
     41d29d5 Comments only
     6506980 Fix solveOneFromTheOther for RecursiveSuperclasses
     be53d19 Use SPDX syntax in rts/package.conf.in
     059596d rts: fix barf format attribute
     6edafe3 Fix isDroppableCt (Trac #14763)
     f489c12 Simplify Foreign.Marshal.Alloc functions with ScopedTypeVariables
     583f561 Evac.c: remove unused CPP guard
     c9a88db Make ($!) representation-polymorphic
     5957405 Collect CCs in CorePrep, including CCs in unfoldings
     0c9777b Fix tests broken by c9a88db3ac4f1c3e97e3492ebe076f2df6463540
     8936ab6 Raise parse error for `data T where`.
     df449e1 Various documentation improvements
     ec9aacf adds -latomic to. ghc-prim
     d5ff33d Adds `smp` flag to rts.cabal.
     e03ca71 Update .cabal files for Cabal 2.1
     0c2350c rts.cabal.in: advertise profiling flavours of libraries, behind a flag
     8529fbb Get eqTypeRep to inline
     7c173b9 Move `iserv` into `utils` and change package name from `iserv-bin` to `iserv`
     d5ac582 Fix #14811 by wiring in $tcUnit#
     a644dff circleci: Add nightly build using devel2 flavour
     9080466 base: Fix changelog entry for openTempFile
     1ede46d Implement stopgap solution for #14728
     918c0b3 Add valid refinement substitution suggestions for typed holes
     9ff4cce Build Haddocks with --quickjump
     bfb90bc Remove doubled words
     ccda486 Tidy up and consolidate canned CmmReg and CmmGlobals
     c05529c myThreadId# is trivial; make it an inline primop
     4e513bf CBE: re-introduce bgamari's fixes
     d924c17 testsuite: Add newline to test output
     fc33f8b Improve error message for UNPACK/strictness annotations.
     7f389a5 StgLint overhaul
     043466b Rename the types in a GADT constructor in toposorted order
     5b63240 Increase the amount of parallelism in circleci.
     9fc4608 Bump haddock submodule again
     2382bbf Bump process submodule
     fc04a8f Bump filepath submodule
     d20524e Bump pretty submodule
     9ad3fa1 Bump stm submodule to 2.4.5.0
     bd0af2a Bump primitive submodule to 0.6.3.0
     e26d774 Bump parsec submodule to 0.3.13.0
     1ee5abc Bump haskeline submodule to 0.7.4.2
     2cb19b4 Bump text submodule to 1.2.3.0
     71294f3 testsuite: Bump allocations for T1969 and T5837
     eb2daa2 Change how includes for input file directory works
     517c194 Document missing dataToTag# . tagToEnum# rule
     81a5e05 circleci: Skip performance tests
     f511bb5 Add ghc-prim.buildinfo to .gitignore
     f433659 Slight refactor of stock deriving internals
     abfe104 Revert "Move `iserv` into `utils` and change package name
     a032ff7 Add references to #6087
     0a3629a Don't use ld.gold when building libraries for GHCi
     3483423 Comments in Unify, fixing #12442
     bf3f0a6 Update Hadrian submodule
     c969c98 driver/utils/dynwrapper.c: Remove unused variable
     be498a2 RTS: Remember to free some pointers
     cb89ba8 RTS: Remove unused retainer schemes
     3d43fd5 Introduce the flag -dsuppress-timestamps to avoid timestamps in dumps.
     5e5e60d boot: Create GNUmakefiles for libraries
     f57c305 testsuite: Bump allocations for T9630
     ffdb110 Update .gitignore
     da4766c circleci: Simplify Hadrian build
     8c1d6b7 Tiny refactor in Core Lint
     40fa420 Comments only
     e99fdf7 Fix a nasty bug in the pure unifier
     d675a35 Better stats for T5837
     3dec923 Test for Trac #13075 is working now
     51e0a38 Comments only
     b2996f1 Fix test for Trac #13075
     df2c3b3 Build quick flavor and run some tests on Windows
     2756117 Revert "Better stats for T5837"
     b8f03bb Cache the fingerprint of sOpt_P
     e261b85 forkProcess: fix task mutex release order
     8dab89b rts: Note functions which must take all_tasks_mutex.
     f8e3cd3 Only load plugins once
     d8e47a2 Make cost centre symbol names deterministic.
     8c7a155 Move Data.Functor.Contravariant from the contravariant package to base.
     e8e9f6a Improve exhaustive checking for guards in pattern bindings and MultiIf.
     125d151 Add regression test for #12790
     aef2b42 Fix #14817 by not double-printing data family instance kind signatures
     4a0d0d8 Various Windows / Cross Compile to Windows fixes
     1773964 DynFlags: Support British spelling of GeneralisedNewtypeDeriving
     969e747 GHCi info: Use src file for cache invalidation
     6a7e159 Improve missing-home-modules warning formatting
     5c28ee8 Add @since annotations for derived instances in base
     6e4fa81 rts/win32: Assert that the IO manager has been initialised
     bc1bcaa configure: Enable LD_NO_GOLD is set in all codepaths
     7782b47 Add Applicative, Semigroup, and Monoid instances in GHC.Generics
     e4dcebf Adds *-cross-ncg flavour.
     6835702 Permit conversion of partially applied PromotedTupleTs
     ffb2738 Fix #14838 by marking TH-spliced code as FromSource
     5f6fcf7 Compile with `--via-asm` when cross compiling.
     44ba60f doCorePass: Expand catch-all
     821daad Correct default -A value in RTS flag usage info
     a2d03c6 Fix the coverage checker's treatment of existential tyvars
     99c556d Parenthesize (() :: Constraint) in argument position
     4631ceb Bump hsc2hs submodule
     8f0b2f5 Bump Cabal submodule to 2.2
     a9f680f Bump Cabal submodule
     e7653bc Wombling around in Trac #14808
     3d25203 Respect Note [The tcType invariant]
     6ee831f Fix #14888 by adding more special cases for ArrowT
     1c062b7 Simplify rnLHsInstType
     df7ac37 Fixup include of gmp/config.mk to use new location
     f6cf400 `--via-asm` only for windows targets
     cf5bc96 add CCX=$(CXX) to integer-gmp
     ee597e9 Schedule.c: remove a redundant CPP guard
     5bc195a Allow top level ticked string literals
     9bccfcd Correct -g flag description
     64c0af7 cmm/: Avoid using lazy left folds
     08345bd Make accumArray and accum stricter
     1488591 Bump nofib submodule
     488d63d Fix interpreter with profiling
     40c4313 Add perf test for #14052
     b120e64 Add bindist-list.uniq to .gitignore
     d9d4632 Schedule.c: remove unreachable code block
     4a6eb16 Merge branch 'master' into wip/kavon-nosplit-llvm
     54321d5 fix build due to the removal of Hoopl.Unique

From git at git.haskell.org  Thu Mar  8 06:01:01 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Thu,  8 Mar 2018 06:01:01 +0000 (UTC)
Subject: [commit: ghc] wip/angerman/win32-cross-2: Cleanup LD detection.
 (cc438e0)
Message-ID: <20180308060101.32EFC3A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/angerman/win32-cross-2
Link       : http://ghc.haskell.org/trac/ghc/changeset/cc438e0aba6003da5891267e373686eff25a8dbf/ghc

>---------------------------------------------------------------

commit cc438e0aba6003da5891267e373686eff25a8dbf
Author: Moritz Angermann <moritz.angermann at gmail.com>
Date:   Thu Mar 8 11:12:46 2018 +0800

    Cleanup LD detection.


>---------------------------------------------------------------

cc438e0aba6003da5891267e373686eff25a8dbf
 aclocal.m4      | 3 ++-
 mk/config.mk.in | 2 +-
 2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/aclocal.m4 b/aclocal.m4
index a2fdbdc..cc25517 100644
--- a/aclocal.m4
+++ b/aclocal.m4
@@ -2359,7 +2359,8 @@ AC_DEFUN([FIND_LD],[
                    FP_CC_LINKER_FLAG_TRY(bfd, $2) ;;
               "GNU gold"*)
                    FP_CC_LINKER_FLAG_TRY(gold, $2)
-                   LD_NO_GOLD=ld
+                   LD_NO_GOLD=
+                   AC_CHECK_TARGET_TOOL([LD_NO_GOLD],[ld])
                    ;;
               "LLD"*)
                    FP_CC_LINKER_FLAG_TRY(lld, $2) ;;
diff --git a/mk/config.mk.in b/mk/config.mk.in
index 92830fa..846857d 100644
--- a/mk/config.mk.in
+++ b/mk/config.mk.in
@@ -537,7 +537,7 @@ AS_STAGE1       = $(AS)
 AS_STAGE2       = $(AS)
 AS_STAGE3       = $(AS)
 
-# why no LD=@LD@ ?
+LD              = @LD@
 LD_STAGE0       = @LD_STAGE0@
 LD_STAGE1       = $(LD)
 LD_STAGE2       = $(LD)


From git at git.haskell.org  Thu Mar  8 06:01:05 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Thu,  8 Mar 2018 06:01:05 +0000 (UTC)
Subject: [commit: ghc] wip/angerman/win32-cross-2: Rename iserv-slave to
 remote-iserv (5ef6e56)
Message-ID: <20180308060105.2FDA43A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/angerman/win32-cross-2
Link       : http://ghc.haskell.org/trac/ghc/changeset/5ef6e5683e9700e04c7dfab5f61f0d01bdc8538d/ghc

>---------------------------------------------------------------

commit 5ef6e5683e9700e04c7dfab5f61f0d01bdc8538d
Author: Moritz Angermann <moritz.angermann at gmail.com>
Date:   Thu Mar 8 14:00:44 2018 +0800

    Rename iserv-slave to remote-iserv


>---------------------------------------------------------------

5ef6e5683e9700e04c7dfab5f61f0d01bdc8538d
 .../.ghc.environment.arm-linux-8.5.20180307        | 31 ++++++++++++++++++++++
 utils/{iserv-slave => remote-iserv}/cabal.project  |  0
 .../remote-iserv.cabal}                            |  7 +++--
 utils/{iserv-slave => remote-iserv}/src/Cli.hs     |  0
 4 files changed, 34 insertions(+), 4 deletions(-)

diff --git a/utils/remote-iserv/.ghc.environment.arm-linux-8.5.20180307 b/utils/remote-iserv/.ghc.environment.arm-linux-8.5.20180307
new file mode 100644
index 0000000..a0a38d3
--- /dev/null
+++ b/utils/remote-iserv/.ghc.environment.arm-linux-8.5.20180307
@@ -0,0 +1,31 @@
+-- This is a GHC environment file written by cabal. This means you can
+-- run ghc or ghci and get the environment of the project as a whole.
+-- But you still need to use cabal repl $target to get the environment
+-- of specific components (libs, exes, tests etc) because each one can
+-- have its own source dirs, cpp flags etc.
+-- 
+clear-package-db
+global-package-db
+package-db /Users/angerman/.cabal/store/ghc-8.5.20180307/package.db
+package-db dist-newstyle/packagedb/ghc-8.5.20180307
+package-id libiserv-8.5-inplace
+package-id base-4.11.0.0
+package-id rts
+package-id ghc-prim-0.5.2.0
+package-id integer-simple-0.1.1.1
+package-id binary-0.8.5.1
+package-id bytestring-0.10.8.2
+package-id deepseq-1.4.3.0
+package-id array-0.5.2.0
+package-id containers-0.5.11.0
+package-id directory-1.3.1.5
+package-id time-1.8.0.2
+package-id filepath-1.4.2
+package-id unix-2.7.2.2
+package-id ghci-8.5
+package-id ghc-boot-8.5
+package-id ghc-boot-th-8.5
+package-id template-haskell-2.13.0.0
+package-id pretty-1.1.3.6
+package-id transformers-0.5.5.0
+package-id ntwrk-2.6.3.4-c7c07d3b
diff --git a/utils/iserv-slave/cabal.project b/utils/remote-iserv/cabal.project
similarity index 100%
rename from utils/iserv-slave/cabal.project
rename to utils/remote-iserv/cabal.project
diff --git a/utils/iserv-slave/iserv-slave.cabal b/utils/remote-iserv/remote-iserv.cabal
similarity index 77%
rename from utils/iserv-slave/iserv-slave.cabal
rename to utils/remote-iserv/remote-iserv.cabal
index 66a2a32..2dc599e 100644
--- a/utils/iserv-slave/iserv-slave.cabal
+++ b/utils/remote-iserv/remote-iserv.cabal
@@ -1,4 +1,4 @@
-Name: iserv-slave
+Name: remote-iserv
 Version: 8.5
 Copyright: XXX
 License: BSD3
@@ -11,10 +11,9 @@ Category: Development
 build-type: Simple
 cabal-version: >=1.10
 
-Executable iserv-slave
+Executable remote-iserv
    Default-Language: Haskell2010
    Main-Is: Cli.hs
    Hs-Source-Dirs: src
-   Build-Depends:
-                  base       >= 4   && < 5,
+   Build-Depends: base       >= 4   && < 5,
                   libiserv   == 8.5
diff --git a/utils/iserv-slave/src/Cli.hs b/utils/remote-iserv/src/Cli.hs
similarity index 100%
rename from utils/iserv-slave/src/Cli.hs
rename to utils/remote-iserv/src/Cli.hs


From git at git.haskell.org  Thu Mar  8 08:36:34 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Thu,  8 Mar 2018 08:36:34 +0000 (UTC)
Subject: [commit: ghc] master: Add -fexternal-dynamic-refs (d99a65a)
Message-ID: <20180308083634.948233A5F6@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/d99a65a80cb671363fa41c826b95b9a89de60878/ghc

>---------------------------------------------------------------

commit d99a65a80cb671363fa41c826b95b9a89de60878
Author: Simon Marlow <smarlow at fb.com>
Date:   Wed Feb 28 11:03:37 2018 -0800

    Add -fexternal-dynamic-refs
    
    Summary:
    The `-dynamic` flag does two things:
    
    * In the code generator, it generates code designed to link against
      external shared libraries.  References outside of the current module
      go through platform-specific indirection tables (e.g. the GOT on ELF).
    
    * It enables a "way", which changes which hi files we look
      for (`Foo.dyn_hi`) and which libraries we link against.
    
    Some specialised applications want the first of these without the
    second. (I could go into detail here but it's probably not all that
    important).
    
    This diff splits out the code-generation effects of `-dynamic` from the
    "way" parts of its behaviour, via a new flag `-fexternal-dynamic-refs`.
    
    Test Plan: validate
    
    Reviewers: niteria, bgamari, erikd
    
    Subscribers: rwbarton, thomie, carter
    
    Differential Revision: https://phabricator.haskell.org/D4477


>---------------------------------------------------------------

d99a65a80cb671363fa41c826b95b9a89de60878
 compiler/cmm/CLabel.hs                      | 15 +++++++++------
 compiler/main/DynFlags.hs                   |  4 +++-
 compiler/nativeGen/PIC.hs                   | 13 ++++++++-----
 docs/users_guide/8.6.1-notes.rst            |  5 +++++
 docs/users_guide/phases.rst                 | 20 ++++++++++++++------
 testsuite/tests/ghci/scripts/T9293.stdout   |  4 ++++
 testsuite/tests/ghci/scripts/ghci024.stdout |  1 +
 testsuite/tests/ghci/scripts/ghci057.stdout |  4 ++++
 8 files changed, 48 insertions(+), 18 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc d99a65a80cb671363fa41c826b95b9a89de60878

From git at git.haskell.org  Thu Mar  8 19:35:03 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Thu,  8 Mar 2018 19:35:03 +0000 (UTC)
Subject: [commit: ghc] master: Revert "GHCi: Don't remove shadowed bindings
 from typechecker scope." (98c7749)
Message-ID: <20180308193503.C21EE3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/98c7749cd360293bee96034056e260d70224cef6/ghc

>---------------------------------------------------------------

commit 98c7749cd360293bee96034056e260d70224cef6
Author: Ömer Sinan Ağacan <omeragacan at gmail.com>
Date:   Thu Mar 8 21:42:22 2018 +0300

    Revert "GHCi: Don't remove shadowed bindings from typechecker scope."
    
    This reverts commit 59d7ee53906b9cee7f279c1f9567af7b930f8636 and enables
    the test for #14052.
    
    (See #14052 for the discussion)
    
    Reviewers: bgamari
    
    Reviewed By: bgamari
    
    Subscribers: rwbarton, thomie, carter
    
    GHC Trac Issues: #14052
    
    Differential Revision: https://phabricator.haskell.org/D4478


>---------------------------------------------------------------

98c7749cd360293bee96034056e260d70224cef6
 compiler/main/HscTypes.hs                             | 13 +++++++++++--
 testsuite/tests/ghci.debugger/scripts/break011.stdout |  7 -------
 testsuite/tests/ghci.debugger/scripts/hist001.stdout  |  4 ----
 testsuite/tests/ghci.debugger/scripts/hist002.stdout  |  4 ----
 testsuite/tests/ghci/scripts/T11547.script            |  9 ---------
 testsuite/tests/ghci/scripts/T11547.stdout            |  5 -----
 testsuite/tests/ghci/scripts/T2976.stdout             |  2 --
 testsuite/tests/ghci/scripts/all.T                    |  1 -
 testsuite/tests/perf/should_run/all.T                 |  3 +--
 9 files changed, 12 insertions(+), 36 deletions(-)

diff --git a/compiler/main/HscTypes.hs b/compiler/main/HscTypes.hs
index 165f860..cc72752 100644
--- a/compiler/main/HscTypes.hs
+++ b/compiler/main/HscTypes.hs
@@ -1641,7 +1641,7 @@ extendInteractiveContext ictxt new_tythings new_cls_insts new_fam_insts defaults
   = ictxt { ic_mod_index  = ic_mod_index ictxt + 1
                             -- Always bump this; even instances should create
                             -- a new mod_index (Trac #9426)
-          , ic_tythings   = new_tythings ++ ic_tythings ictxt
+          , ic_tythings   = new_tythings ++ old_tythings
           , ic_rn_gbl_env = ic_rn_gbl_env ictxt `icExtendGblRdrEnv` new_tythings
           , ic_instances  = ( new_cls_insts ++ old_cls_insts
                             , new_fam_insts ++ fam_insts )
@@ -1651,6 +1651,8 @@ extendInteractiveContext ictxt new_tythings new_cls_insts new_fam_insts defaults
           , ic_fix_env    = fix_env  -- See Note [Fixity declarations in GHCi]
           }
   where
+    new_ids = [id | AnId id <- new_tythings]
+    old_tythings = filterOut (shadowed_by new_ids) (ic_tythings ictxt)
 
     -- Discard old instances that have been fully overridden
     -- See Note [Override identical instances in GHCi]
@@ -1662,10 +1664,17 @@ extendInteractiveContextWithIds :: InteractiveContext -> [Id] -> InteractiveCont
 extendInteractiveContextWithIds ictxt new_ids
   | null new_ids = ictxt
   | otherwise    = ictxt { ic_mod_index  = ic_mod_index ictxt + 1
-                         , ic_tythings   = new_tythings ++ ic_tythings ictxt
+                         , ic_tythings   = new_tythings ++ old_tythings
                          , ic_rn_gbl_env = ic_rn_gbl_env ictxt `icExtendGblRdrEnv` new_tythings }
   where
     new_tythings = map AnId new_ids
+    old_tythings = filterOut (shadowed_by new_ids) (ic_tythings ictxt)
+
+shadowed_by :: [Id] -> TyThing -> Bool
+shadowed_by ids = shadowed
+  where
+    shadowed id = getOccName id `elemOccSet` new_occs
+    new_occs = mkOccSet (map getOccName ids)
 
 setInteractivePackage :: HscEnv -> HscEnv
 -- Set the 'thisPackage' DynFlag to 'interactive'
diff --git a/testsuite/tests/ghci.debugger/scripts/break011.stdout b/testsuite/tests/ghci.debugger/scripts/break011.stdout
index ac5b7e3..47fb7b1 100644
--- a/testsuite/tests/ghci.debugger/scripts/break011.stdout
+++ b/testsuite/tests/ghci.debugger/scripts/break011.stdout
@@ -23,13 +23,6 @@ _exception = SomeException
                   "foo"
                   "CallStack (from HasCallStack):
   error, called at Test7.hs:2:18 in main:Main")
-Ghci1._exception :: SomeException = SomeException
-                                      (ErrorCallWithLocation
-                                         "foo"
-                                         "CallStack (from HasCallStack):
-  error, called at Test7.hs:<line>:<column> in <package-id>:Main")
-Ghci2._result :: a = _
-Ghci3._result :: IO a = _
 _result :: a = _
 _exception :: SomeException = SomeException
                                 (ErrorCallWithLocation
diff --git a/testsuite/tests/ghci.debugger/scripts/hist001.stdout b/testsuite/tests/ghci.debugger/scripts/hist001.stdout
index 523605b..a19a34f 100644
--- a/testsuite/tests/ghci.debugger/scripts/hist001.stdout
+++ b/testsuite/tests/ghci.debugger/scripts/hist001.stdout
@@ -12,7 +12,6 @@ Logged breakpoint at Test3.hs:2:22-31
 _result :: [a]
 f :: t -> a
 xs :: [t]
-Ghci1._result :: [a] = _
 xs :: [t] = []
 f :: t -> a = _
 _result :: [a] = _
@@ -20,10 +19,7 @@ Logged breakpoint at Test3.hs:2:18-20
 _result :: a
 f :: Integer -> a
 x :: Integer
-Ghci1._result :: [a] = _
 xs :: [t] = []
-Ghci2.f :: t -> a = _
-Ghci2._result :: [a] = _
 x :: Integer = 2
 f :: Integer -> a = _
 _result :: a = _
diff --git a/testsuite/tests/ghci.debugger/scripts/hist002.stdout b/testsuite/tests/ghci.debugger/scripts/hist002.stdout
index 523605b..a19a34f 100644
--- a/testsuite/tests/ghci.debugger/scripts/hist002.stdout
+++ b/testsuite/tests/ghci.debugger/scripts/hist002.stdout
@@ -12,7 +12,6 @@ Logged breakpoint at Test3.hs:2:22-31
 _result :: [a]
 f :: t -> a
 xs :: [t]
-Ghci1._result :: [a] = _
 xs :: [t] = []
 f :: t -> a = _
 _result :: [a] = _
@@ -20,10 +19,7 @@ Logged breakpoint at Test3.hs:2:18-20
 _result :: a
 f :: Integer -> a
 x :: Integer
-Ghci1._result :: [a] = _
 xs :: [t] = []
-Ghci2.f :: t -> a = _
-Ghci2._result :: [a] = _
 x :: Integer = 2
 f :: Integer -> a = _
 _result :: a = _
diff --git a/testsuite/tests/ghci/scripts/T11547.script b/testsuite/tests/ghci/scripts/T11547.script
deleted file mode 100644
index c4c15d6..0000000
--- a/testsuite/tests/ghci/scripts/T11547.script
+++ /dev/null
@@ -1,9 +0,0 @@
-foo = foo
-:t Ghci1.foo
-foo = foo
-:t Ghci2.foo
-:t Ghci1.foo
-data Foo = Foo | Bar
-data Foo = Bar
-:t Foo
-:t Ghci3.Bar
diff --git a/testsuite/tests/ghci/scripts/T11547.stdout b/testsuite/tests/ghci/scripts/T11547.stdout
deleted file mode 100644
index 6f2a833..0000000
--- a/testsuite/tests/ghci/scripts/T11547.stdout
+++ /dev/null
@@ -1,5 +0,0 @@
-Ghci1.foo :: t
-Ghci2.foo :: t
-Ghci1.foo :: t
-Foo :: Ghci3.Foo
-Ghci3.Bar :: Ghci3.Foo
diff --git a/testsuite/tests/ghci/scripts/T2976.stdout b/testsuite/tests/ghci/scripts/T2976.stdout
index de31112..9fdc110 100644
--- a/testsuite/tests/ghci/scripts/T2976.stdout
+++ b/testsuite/tests/ghci/scripts/T2976.stdout
@@ -1,8 +1,6 @@
 test :: Integer = 0
 test = 0
 test :: Integer = 0
-Ghci1.test :: Integer = 0
 test :: [Char] = _
 test = "test"
-Ghci1.test :: Integer = 0
 test :: [Char] = "test"
diff --git a/testsuite/tests/ghci/scripts/all.T b/testsuite/tests/ghci/scripts/all.T
index dcce723..f0d90b6 100755
--- a/testsuite/tests/ghci/scripts/all.T
+++ b/testsuite/tests/ghci/scripts/all.T
@@ -238,7 +238,6 @@ test('T11376', normal, ghci_script, ['T11376.script'])
 test('T12007', normal, ghci_script, ['T12007.script'])
 test('T11975', normal, ghci_script, ['T11975.script'])
 test('T10963', normal, ghci_script, ['T10963.script'])
-test('T11547', normal, ghci_script, ['T11547.script'])
 test('T11721', normal, ghci_script, ['T11721.script'])
 test('T12520', normal, ghci_script, ['T12520.script'])
 test('T12091', [extra_run_opts('-fobject-code')], ghci_script,
diff --git a/testsuite/tests/perf/should_run/all.T b/testsuite/tests/perf/should_run/all.T
index 50ccac0..d5261b8 100644
--- a/testsuite/tests/perf/should_run/all.T
+++ b/testsuite/tests/perf/should_run/all.T
@@ -553,7 +553,6 @@ test('T13623',
 
 test('T14052',
      [stats_num_field('bytes allocated',
-                      [ (wordsize(64), 2785811496, 10) ]),
-      expect_broken(14052)],
+                      [ (wordsize(64), 2346183840, 10) ])],
      ghci_script,
      ['T14052.script'])


From git at git.haskell.org  Thu Mar  8 22:05:27 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Thu,  8 Mar 2018 22:05:27 +0000 (UTC)
Subject: [commit: ghc] master: Error message and doc improvements for #14335
 (bc95fed)
Message-ID: <20180308220527.37C713A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/bc95fedc0b1f45b62ba279f7df834c490c2e53b6/ghc

>---------------------------------------------------------------

commit bc95fedc0b1f45b62ba279f7df834c490c2e53b6
Author: Ömer Sinan Ağacan <omeragacan at gmail.com>
Date:   Thu Mar 8 13:19:33 2018 -0500

    Error message and doc improvements for #14335
    
    - Show a more friendly error message when -fplugin is used with
      -fexternal-interpreter
    
    - Add a few words to users guide about the interaction with -fplugin and
      -fexternal-interpreter
    
    - Update test for #14335
    
    Reviewers: bgamari
    
    Reviewed By: bgamari
    
    Subscribers: rwbarton, thomie, carter
    
    GHC Trac Issues: #14335
    
    Differential Revision: https://phabricator.haskell.org/D4456


>---------------------------------------------------------------

bc95fedc0b1f45b62ba279f7df834c490c2e53b6
 compiler/main/DynamicLoading.hs       | 22 ++++++++++++++++++----
 docs/users_guide/extending_ghc.rst    |  3 +++
 testsuite/tests/plugins/Makefile      |  5 -----
 testsuite/tests/plugins/T14335.hs     |  1 +
 testsuite/tests/plugins/T14335.stderr |  1 +
 testsuite/tests/plugins/all.T         |  7 ++++---
 6 files changed, 27 insertions(+), 12 deletions(-)

diff --git a/compiler/main/DynamicLoading.hs b/compiler/main/DynamicLoading.hs
index 3dc4981..90a099f 100644
--- a/compiler/main/DynamicLoading.hs
+++ b/compiler/main/DynamicLoading.hs
@@ -57,6 +57,7 @@ import Outputable
 import Exception
 import Hooks
 
+import Control.Monad     ( when, unless )
 import Data.Maybe        ( mapMaybe )
 import GHC.Exts          ( unsafeCoerce# )
 
@@ -96,7 +97,9 @@ initializePlugins hsc_env df
 
 loadPlugins :: HscEnv -> IO [LoadedPlugin]
 loadPlugins hsc_env
-  = do { plugins <- mapM (loadPlugin hsc_env) to_load
+  = do { unless (null to_load) $
+           checkExternalInterpreter hsc_env
+       ; plugins <- mapM loadPlugin to_load
        ; return $ zipWith attachOptions to_load plugins }
   where
     dflags  = hsc_dflags hsc_env
@@ -107,11 +110,22 @@ loadPlugins hsc_env
         options = [ option | (opt_mod_nm, option) <- pluginModNameOpts dflags
                             , opt_mod_nm == mod_nm ]
 
-loadPlugin :: HscEnv -> ModuleName -> IO Plugin
-loadPlugin = loadPlugin' (mkVarOcc "plugin") pluginTyConName
+    loadPlugin = loadPlugin' (mkVarOcc "plugin") pluginTyConName hsc_env
 
 loadFrontendPlugin :: HscEnv -> ModuleName -> IO FrontendPlugin
-loadFrontendPlugin = loadPlugin' (mkVarOcc "frontendPlugin") frontendPluginTyConName
+loadFrontendPlugin hsc_env mod_name = do
+    checkExternalInterpreter hsc_env
+    loadPlugin' (mkVarOcc "frontendPlugin") frontendPluginTyConName
+                hsc_env mod_name
+
+-- #14335
+checkExternalInterpreter :: HscEnv -> IO ()
+checkExternalInterpreter hsc_env =
+    when (gopt Opt_ExternalInterpreter dflags) $
+      throwCmdLineError $ showSDoc dflags $
+        text "Plugins require -fno-external-interpreter"
+  where
+    dflags = hsc_dflags hsc_env
 
 loadPlugin' :: OccName -> Name -> HscEnv -> ModuleName -> IO a
 loadPlugin' occ_name plugin_name hsc_env mod_name
diff --git a/docs/users_guide/extending_ghc.rst b/docs/users_guide/extending_ghc.rst
index e49effb..12043a0 100644
--- a/docs/users_guide/extending_ghc.rst
+++ b/docs/users_guide/extending_ghc.rst
@@ -185,6 +185,9 @@ the constraint solver. If you feel strongly that any of these
 restrictions are too onerous,
 :ghc-wiki:`please give the GHC team a shout <MailingListsAndIRC>`.
 
+Plugins do not work with ``-fexternal-interpreter``. If you need to run plugins
+with ``-fexternal-interpreter`` let GHC developers know in :ghc-ticket:`14335`.
+
 .. _using-compiler-plugins:
 
 Using compiler plugins
diff --git a/testsuite/tests/plugins/Makefile b/testsuite/tests/plugins/Makefile
index 96443c9..1ff8d40 100644
--- a/testsuite/tests/plugins/Makefile
+++ b/testsuite/tests/plugins/Makefile
@@ -52,8 +52,3 @@ T12567a:
 	"$(TEST_HC)" $(TEST_HC_OPTS) $(ghcPluginWayFlags) --make T12567a.hs -package-db simple-plugin/pkg.T12567a/local.package.conf -hide-all-plugin-packages -plugin-package simple-plugin 1>&2
 	"$(TEST_HC)" $(TEST_HC_OPTS) $(ghcPluginWayFlags) --make T12567a.hs -package-db simple-plugin/pkg.T12567a/local.package.conf -hide-all-plugin-packages -plugin-package simple-plugin 2>&1 | grep "T12567a.hs, T12567a.o" 1>&2
 	"$(TEST_HC)" $(TEST_HC_OPTS) $(ghcPluginWayFlags) --make T12567b.hs -package-db simple-plugin/pkg.T12567a/local.package.conf -hide-all-plugin-packages -plugin-package simple-plugin 1>&2
-
-.PHONY: T14335
-T14335:
-	"$(TEST_HC)" $(TEST_HC_OPTS) $(ghcPluginWayFlags) -fexternal-interpreter --make -v0 plugins01.hs -package-db simple-plugin/pkg.plugins01/local.package.conf -fplugin Simple.Plugin -fplugin-opt Simple.Plugin:Irrelevant_Option -hide-all-plugin-packages -plugin-package simple-plugin
-	./plugins01
diff --git a/testsuite/tests/plugins/T14335.hs b/testsuite/tests/plugins/T14335.hs
new file mode 100644
index 0000000..49a0085
--- /dev/null
+++ b/testsuite/tests/plugins/T14335.hs
@@ -0,0 +1 @@
+module T14335 where
diff --git a/testsuite/tests/plugins/T14335.stderr b/testsuite/tests/plugins/T14335.stderr
new file mode 100644
index 0000000..1f051a7
--- /dev/null
+++ b/testsuite/tests/plugins/T14335.stderr
@@ -0,0 +1 @@
+<command line>: Plugins require -fno-external-interpreter
diff --git a/testsuite/tests/plugins/all.T b/testsuite/tests/plugins/all.T
index 0e523f0..5786637 100644
--- a/testsuite/tests/plugins/all.T
+++ b/testsuite/tests/plugins/all.T
@@ -70,6 +70,7 @@ test('T12567a',
 
 test('T14335',
      [extra_files(['simple-plugin/', 'plugins01.hs']),
-      pre_cmd('$MAKE -s --no-print-directory -C simple-plugin package.plugins01 TOP={top}'),
-      expect_broken(14335)],
-     run_command, ['$MAKE -s --no-print-directory T14335'])
+      pre_cmd('$MAKE -s --no-print-directory -C simple-plugin package.plugins01 TOP={top}')],
+     compile_fail,
+     ['-package-db simple-plugin/pkg.plugins01/local.package.conf -fplugin Simple.Plugin \
+       -fexternal-interpreter -package simple-plugin ' + config.plugin_way_flags])


From git at git.haskell.org  Thu Mar  8 22:05:40 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Thu,  8 Mar 2018 22:05:40 +0000 (UTC)
Subject: [commit: ghc] master: ghc-prim: Reduce scope of Clang
 sync_fetch_and_nand workaround (ed6f9fb)
Message-ID: <20180308220540.C78F83A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/ed6f9fb9d5a684d2159c29633159c3254cf04deb/ghc

>---------------------------------------------------------------

commit ed6f9fb9d5a684d2159c29633159c3254cf04deb
Author: Ben Gamari <bgamari.foss at gmail.com>
Date:   Thu Mar 8 13:22:22 2018 -0500

    ghc-prim: Reduce scope of Clang sync_fetch_and_nand workaround
    
    As described in https://bugs.llvm.org/show_bug.cgi?id=8842, Clang
    removed the __sync_fetch_and_nand builtins due to inconsistency in GCC's
    behavior in 2010.  However, GCC has since clarified the behavior of
    their builtins and consequently Clang re-added them in 2014.
    Consequently this workaround should no longer be necessary.
    
    Test Plan: Validate building with Clang
    
    Subscribers: rwbarton, thomie, carter
    
    Differential Revision: https://phabricator.haskell.org/D4480


>---------------------------------------------------------------

ed6f9fb9d5a684d2159c29633159c3254cf04deb
 libraries/ghc-prim/cbits/atomic.c | 13 +++++++++----
 1 file changed, 9 insertions(+), 4 deletions(-)

diff --git a/libraries/ghc-prim/cbits/atomic.c b/libraries/ghc-prim/cbits/atomic.c
index 2ded465..722d261 100644
--- a/libraries/ghc-prim/cbits/atomic.c
+++ b/libraries/ghc-prim/cbits/atomic.c
@@ -117,11 +117,16 @@ hs_atomic_and64(StgWord x, StgWord64 val)
     return tmp;                                                     \
   }
 
+// This is only provided by clang
+#if !defined(__has_builtin)
+#define __has_builtin(x) 0
+#endif
+
 extern StgWord hs_atomic_nand8(StgWord x, StgWord val);
 StgWord
 hs_atomic_nand8(StgWord x, StgWord val)
 {
-#ifdef __clang__
+#if defined(__clang__) && __has_builtin(__sync_fetch_and_nand)
   CAS_NAND((volatile StgWord8 *) x, (StgWord8) val)
 #else
   return __sync_fetch_and_nand((volatile StgWord8 *) x, (StgWord8) val);
@@ -132,7 +137,7 @@ extern StgWord hs_atomic_nand16(StgWord x, StgWord val);
 StgWord
 hs_atomic_nand16(StgWord x, StgWord val)
 {
-#ifdef __clang__
+#if defined(__clang__) && __has_builtin(__sync_fetch_and_nand)
   CAS_NAND((volatile StgWord16 *) x, (StgWord16) val);
 #else
   return __sync_fetch_and_nand((volatile StgWord16 *) x, (StgWord16) val);
@@ -143,7 +148,7 @@ extern StgWord hs_atomic_nand32(StgWord x, StgWord val);
 StgWord
 hs_atomic_nand32(StgWord x, StgWord val)
 {
-#ifdef __clang__
+#if defined(__clang__) && __has_builtin(__sync_fetch_and_nand)
   CAS_NAND((volatile StgWord32 *) x, (StgWord32) val);
 #else
   return __sync_fetch_and_nand((volatile StgWord32 *) x, (StgWord32) val);
@@ -155,7 +160,7 @@ extern StgWord64 hs_atomic_nand64(StgWord x, StgWord64 val);
 StgWord64
 hs_atomic_nand64(StgWord x, StgWord64 val)
 {
-#ifdef __clang__
+#if defined(__clang__) && __has_builtin(__sync_fetch_and_nand)
   CAS_NAND((volatile StgWord64 *) x, val);
 #else
   return __sync_fetch_and_nand((volatile StgWord64 *) x, val);


From git at git.haskell.org  Thu Mar  8 22:05:55 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Thu,  8 Mar 2018 22:05:55 +0000 (UTC)
Subject: [commit: ghc] master: ghc-prim: Silence -Wsync-nand warning in
 atomic.c (94f0254)
Message-ID: <20180308220555.2D1B33A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/94f02547083cf6df686ea0b95fed050184c533de/ghc

>---------------------------------------------------------------

commit 94f02547083cf6df686ea0b95fed050184c533de
Author: Ben Gamari <bgamari.foss at gmail.com>
Date:   Thu Mar 8 13:22:37 2018 -0500

    ghc-prim: Silence -Wsync-nand warning in atomic.c
    
    GCC throws this warning to inform us that __sync_fetch_and_nand's
    behavior changed in GCC 4.4. However, this causes the build to fail when
    -Werror is used.
    
    Test Plan: Validate with -Werror
    
    Subscribers: rwbarton, thomie, carter
    
    Differential Revision: https://phabricator.haskell.org/D4481


>---------------------------------------------------------------

94f02547083cf6df686ea0b95fed050184c533de
 libraries/ghc-prim/cbits/atomic.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/libraries/ghc-prim/cbits/atomic.c b/libraries/ghc-prim/cbits/atomic.c
index 722d261..80d4f39 100644
--- a/libraries/ghc-prim/cbits/atomic.c
+++ b/libraries/ghc-prim/cbits/atomic.c
@@ -122,6 +122,10 @@ hs_atomic_and64(StgWord x, StgWord64 val)
 #define __has_builtin(x) 0
 #endif
 
+// Otherwise this fails with -Werror
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wsync-nand"
+
 extern StgWord hs_atomic_nand8(StgWord x, StgWord val);
 StgWord
 hs_atomic_nand8(StgWord x, StgWord val)
@@ -168,6 +172,8 @@ hs_atomic_nand64(StgWord x, StgWord64 val)
 }
 #endif
 
+#pragma GCC diagnostic pop
+
 // FetchOrByteArrayOp_Int
 
 extern StgWord hs_atomic_or8(StgWord x, StgWord val);


From git at git.haskell.org  Thu Mar  8 22:06:13 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Thu,  8 Mar 2018 22:06:13 +0000 (UTC)
Subject: [commit: ghc] master: Remove outdated documentation bits concerning
 -Wmissing-methods (47e2a28)
Message-ID: <20180308220613.4DABB3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/47e2a28d8c8c80aa9309ceb195ee8671b5a76d3e/ghc

>---------------------------------------------------------------

commit 47e2a28d8c8c80aa9309ceb195ee8671b5a76d3e
Author: Ryan Scott <ryan.gl.scott at gmail.com>
Date:   Thu Mar 8 13:23:27 2018 -0500

    Remove outdated documentation bits concerning -Wmissing-methods
    
    In commit 503219e3e1667ac39607021b2d9586260fbab32b, we
    stopped suppressing `-Wmissing-methods` warnings on class methods
    whose names begin with an underscore. However, it seems the users'
    guide documentation concerning this was never updated. Let's do so.
    
    Test Plan: Read it
    
    Reviewers: bgamari
    
    Reviewed By: bgamari
    
    Subscribers: rwbarton, thomie, carter
    
    GHC Trac Issues: #12959
    
    Differential Revision: https://phabricator.haskell.org/D4476


>---------------------------------------------------------------

47e2a28d8c8c80aa9309ceb195ee8671b5a76d3e
 docs/users_guide/glasgow_exts.rst   |  5 ++---
 docs/users_guide/using-warnings.rst | 12 ------------
 2 files changed, 2 insertions(+), 15 deletions(-)

diff --git a/docs/users_guide/glasgow_exts.rst b/docs/users_guide/glasgow_exts.rst
index 5bcd67e..c6cff92 100644
--- a/docs/users_guide/glasgow_exts.rst
+++ b/docs/users_guide/glasgow_exts.rst
@@ -13778,9 +13778,8 @@ Conjunction binds stronger than disjunction.
 
 If no ``MINIMAL`` pragma is given in the class declaration, it is just as if
 a pragma ``{-# MINIMAL op1, op2, ..., opn #-}`` was given, where the
-``opi`` are the methods (a) that lack a default method in the class
-declaration, and (b) whose name that does not start with an underscore
-(c.f. :ghc-flag:`-Wmissing-methods`, :ref:`options-sanity`).
+``opi`` are the methods that lack a default method in the class
+declaration (c.f. :ghc-flag:`-Wmissing-methods`, :ref:`options-sanity`).
 
 This warning can be turned off with the flag
 :ghc-flag:`-Wno-missing-methods <-Wmissing-methods>`.
diff --git a/docs/users_guide/using-warnings.rst b/docs/users_guide/using-warnings.rst
index 8106003..aeb402d 100644
--- a/docs/users_guide/using-warnings.rst
+++ b/docs/users_guide/using-warnings.rst
@@ -925,18 +925,6 @@ of ``-W(no-)*``.
     declaration is missing one or more methods, and the corresponding
     class declaration has no default declaration for them.
 
-    The warning is suppressed if the method name begins with an
-    underscore. Here's an example where this is useful: ::
-
-        class C a where
-            _simpleFn :: a -> String
-            complexFn :: a -> a -> String
-            complexFn x y = ... _simpleFn ...
-
-    The idea is that: (a) users of the class will only call
-    ``complexFn``; never ``_simpleFn``; and (b) instance declarations
-    can define either ``complexFn`` or ``_simpleFn``.
-
     The ``MINIMAL`` pragma can be used to change which combination of
     methods will be required for instances of a particular class. See
     :ref:`minimal-pragma`.


From git at git.haskell.org  Thu Mar  8 22:06:26 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Thu,  8 Mar 2018 22:06:26 +0000 (UTC)
Subject: [commit: ghc] master: configure: Accept suffix in OpenBSD triple's OS
 name (a25b763)
Message-ID: <20180308220626.DD4DD3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/a25b763fa9e09d3bf7c82fef1eaed89a7afc54f7/ghc

>---------------------------------------------------------------

commit a25b763fa9e09d3bf7c82fef1eaed89a7afc54f7
Author: Ben Gamari <bgamari.foss at gmail.com>
Date:   Thu Mar 8 13:29:01 2018 -0500

    configure: Accept suffix in OpenBSD triple's OS name
    
    Reviewers: hvr
    
    Subscribers: rwbarton, thomie, erikd, carter
    
    Differential Revision: https://phabricator.haskell.org/D4483


>---------------------------------------------------------------

a25b763fa9e09d3bf7c82fef1eaed89a7afc54f7
 aclocal.m4 | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/aclocal.m4 b/aclocal.m4
index a2fdbdc..528fd0c 100644
--- a/aclocal.m4
+++ b/aclocal.m4
@@ -1960,8 +1960,11 @@ AC_DEFUN([GHC_CONVERT_OS],[
       linux-*|linux)
         $3="linux"
         ;;
+      openbsd*)
+        $3="openbsd"
+        ;;
       # As far as I'm aware, none of these have relevant variants
-      freebsd|netbsd|openbsd|dragonfly|hpux|linuxaout|kfreebsdgnu|freebsd2|solaris2|mingw32|darwin|gnu|nextstep2|nextstep3|sunos4|ultrix|haiku)
+      freebsd|netbsd|dragonfly|hpux|linuxaout|kfreebsdgnu|freebsd2|solaris2|mingw32|darwin|gnu|nextstep2|nextstep3|sunos4|ultrix|haiku)
         $3="$1"
         ;;
       aix*) # e.g. powerpc-ibm-aix7.1.3.0


From git at git.haskell.org  Fri Mar  9 09:27:52 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Fri,  9 Mar 2018 09:27:52 +0000 (UTC)
Subject: [commit: ghc] master: Compacted arrays are pinned for
 isByteArrayPinned# (df2ea10)
Message-ID: <20180309092752.8C2883A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/df2ea10655984234924ad9f2c237289ab8f4baa6/ghc

>---------------------------------------------------------------

commit df2ea10655984234924ad9f2c237289ab8f4baa6
Author: Simon Marlow <marlowsd at gmail.com>
Date:   Thu Mar 8 08:54:01 2018 +0000

    Compacted arrays are pinned for isByteArrayPinned#
    
    Test Plan: New unit test
    
    Reviewers: andrewthad, niteria, bgamari, erikd
    
    Subscribers: rwbarton, thomie, carter
    
    GHC Trac Issues: #14900
    
    Differential Revision: https://phabricator.haskell.org/D4485


>---------------------------------------------------------------

df2ea10655984234924ad9f2c237289ab8f4baa6
 rts/PrimOps.cmm                   |  3 ++-
 testsuite/tests/rts/T14900.hs     | 22 ++++++++++++++++++++++
 testsuite/tests/rts/T14900.stdout |  3 +++
 testsuite/tests/rts/all.T         |  2 ++
 4 files changed, 29 insertions(+), 1 deletion(-)

diff --git a/rts/PrimOps.cmm b/rts/PrimOps.cmm
index 6d57fd8..67a2384 100644
--- a/rts/PrimOps.cmm
+++ b/rts/PrimOps.cmm
@@ -160,8 +160,9 @@ stg_isByteArrayPinnedzh ( gcptr ba )
     // Pinned byte arrays live in blocks with the BF_PINNED flag set.
     // We also consider BF_LARGE objects to be immovable. See #13894.
     // See the comment in Storage.c:allocatePinned.
+    // We also consider BF_COMPACT objects to be immovable. See #14900.
     flags = TO_W_(bdescr_flags(bd));
-    return (flags & (BF_PINNED | BF_LARGE) != 0);
+    return (flags & (BF_PINNED | BF_LARGE | BF_COMPACT) != 0);
 }
 
 stg_isMutableByteArrayPinnedzh ( gcptr mba )
diff --git a/testsuite/tests/rts/T14900.hs b/testsuite/tests/rts/T14900.hs
new file mode 100644
index 0000000..bd29289
--- /dev/null
+++ b/testsuite/tests/rts/T14900.hs
@@ -0,0 +1,22 @@
+{-# LANGUAGE MagicHash, UnboxedTuples #-}
+
+import GHC.Compact
+import GHC.Int
+import GHC.Prim
+import GHC.IO
+import GHC.Exts
+
+data BA = ByteArray ByteArray#
+
+newByteArray :: Int -> IO BA
+newByteArray (I# sz) = IO $ \s -> case newByteArray# sz s of {
+  (# s', arr# #) -> case unsafeFreezeByteArray# arr# s of {
+  (# s'', barr# #) -> (# s', ByteArray barr# #) }}
+
+main :: IO ()
+main = do
+  ByteArray arr1# <- fmap getCompact $ newByteArray 65000 >>= compact
+  ByteArray arr2# <- newByteArray 65000
+  print (I# (isByteArrayPinned# arr1#))
+  print (I# (isByteArrayPinned# arr2#))
+  putStrLn "Finished"
diff --git a/testsuite/tests/rts/T14900.stdout b/testsuite/tests/rts/T14900.stdout
new file mode 100644
index 0000000..fdc259d
--- /dev/null
+++ b/testsuite/tests/rts/T14900.stdout
@@ -0,0 +1,3 @@
+1
+1
+Finished
diff --git a/testsuite/tests/rts/all.T b/testsuite/tests/rts/all.T
index ef77d57..5000a91 100644
--- a/testsuite/tests/rts/all.T
+++ b/testsuite/tests/rts/all.T
@@ -388,3 +388,5 @@ test('T14702', [ ignore_stdout
                , extra_run_opts('+RTS -A32m -N8 -T -RTS')
                ]
                , compile_and_run, [''])
+
+test('T14900', normal, compile_and_run, ['-package ghc-compact'])


From git at git.haskell.org  Fri Mar  9 17:57:31 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Fri,  9 Mar 2018 17:57:31 +0000 (UTC)
Subject: [commit: ghc] master: UNREG: fix implicit declarations from pdep and
 pext (dd3906b)
Message-ID: <20180309175731.D0F3F3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/dd3906bf5debdb74bb8e356cede7f6ac6d770007/ghc

>---------------------------------------------------------------

commit dd3906bf5debdb74bb8e356cede7f6ac6d770007
Author: Sergei Trofimovich <slyfox at gentoo.org>
Date:   Fri Mar 9 17:43:01 2018 +0000

    UNREG: fix implicit declarations from pdep and pext
    
    Unreg build failed as:
    
      $ ./configure --enable-unregisterised
      $ make
    
      HC [stage 1] libraries/ghc-prim/dist-install/build/GHC/PrimopWrappers.o
        ghc_1.hc: In function 'ghczmprim_GHCziPrimopWrappers_pdep8zh_entry':
    
        ghc_1.hc:1810:9: error:
         error: implicit declaration of function 'hs_pdep8'; did you mean 'hs_ctz8'?
           [-Werror=implicit-function-declaration]
         _c3jz = hs_pdep8(*Sp, Sp[1]);
                 ^~~~~~~~
                 hs_ctz8
           |
      1810 | _c3jz = hs_pdep8(*Sp, Sp[1]);
           |         ^
    
    Signed-off-by: Sergei Trofimovich <slyfox at gentoo.org>


>---------------------------------------------------------------

dd3906bf5debdb74bb8e356cede7f6ac6d770007
 includes/stg/Prim.h             | 12 ++++++++++++
 libraries/ghc-prim/cbits/pdep.c |  5 -----
 libraries/ghc-prim/cbits/pext.c |  5 -----
 3 files changed, 12 insertions(+), 10 deletions(-)

diff --git a/includes/stg/Prim.h b/includes/stg/Prim.h
index fa3a3ec..a18e02c 100644
--- a/includes/stg/Prim.h
+++ b/includes/stg/Prim.h
@@ -58,6 +58,18 @@ StgWord64 hs_bswap64(StgWord64 x);
 
 /* TODO: longlong.c */
 
+/* libraries/ghc-prim/cbits/pdep.c */
+StgWord64 hs_pdep64(StgWord64 src, StgWord64 mask);
+StgWord hs_pdep32(StgWord src, StgWord mask);
+StgWord hs_pdep16(StgWord src, StgWord mask);
+StgWord hs_pdep8(StgWord src, StgWord mask);
+
+/* libraries/ghc-prim/cbits/pext.c */
+StgWord64 hs_pext64(StgWord64 src, StgWord64 mask);
+StgWord hs_pext32(StgWord src, StgWord mask);
+StgWord hs_pext16(StgWord src, StgWord mask);
+StgWord hs_pext8(StgWord src, StgWord mask);
+
 /* libraries/ghc-prim/cbits/popcnt.c */
 StgWord hs_popcnt8(StgWord x);
 StgWord hs_popcnt16(StgWord x);
diff --git a/libraries/ghc-prim/cbits/pdep.c b/libraries/ghc-prim/cbits/pdep.c
index 8435ffe..58e8611 100644
--- a/libraries/ghc-prim/cbits/pdep.c
+++ b/libraries/ghc-prim/cbits/pdep.c
@@ -1,8 +1,6 @@
 #include "Rts.h"
 #include "MachDeps.h"
 
-extern StgWord64 hs_pdep64(StgWord64 src, StgWord64 mask);
-
 StgWord64
 hs_pdep64(StgWord64 src, StgWord64 mask)
 {
@@ -26,21 +24,18 @@ hs_pdep64(StgWord64 src, StgWord64 mask)
   return result;
 }
 
-extern StgWord hs_pdep32(StgWord src, StgWord mask);
 StgWord
 hs_pdep32(StgWord src, StgWord mask)
 {
   return hs_pdep64(src, mask);
 }
 
-extern StgWord hs_pdep16(StgWord src, StgWord mask);
 StgWord
 hs_pdep16(StgWord src, StgWord mask)
 {
   return hs_pdep64(src, mask);
 }
 
-extern StgWord hs_pdep8(StgWord src, StgWord mask);
 StgWord
 hs_pdep8(StgWord src, StgWord mask)
 {
diff --git a/libraries/ghc-prim/cbits/pext.c b/libraries/ghc-prim/cbits/pext.c
index fe960b1..9cddede 100644
--- a/libraries/ghc-prim/cbits/pext.c
+++ b/libraries/ghc-prim/cbits/pext.c
@@ -1,8 +1,6 @@
 #include "Rts.h"
 #include "MachDeps.h"
 
-extern StgWord64 hs_pext64(StgWord64 src, StgWord64 mask);
-
 StgWord64
 hs_pext64(StgWord64 src, StgWord64 mask)
 {
@@ -22,21 +20,18 @@ hs_pext64(StgWord64 src, StgWord64 mask)
   return result;
 }
 
-extern StgWord hs_pext32(StgWord src, StgWord mask);
 StgWord
 hs_pext32(StgWord src, StgWord mask)
 {
   return hs_pext64(src, mask);
 }
 
-extern StgWord hs_pext16(StgWord src, StgWord mask);
 StgWord
 hs_pext16(StgWord src, StgWord mask)
 {
   return hs_pext64(src, mask);
 }
 
-extern StgWord hs_pext8(StgWord src, StgWord mask);
 StgWord
 hs_pext8(StgWord src, StgWord mask)
 {


From git at git.haskell.org  Sat Mar 10 07:00:07 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Sat, 10 Mar 2018 07:00:07 +0000 (UTC)
Subject: [commit: ghc] master: Fix a debug print in disassembler (#14905)
 (8e34101)
Message-ID: <20180310070007.072603A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/8e3410134bd7419db638988d74fcc600b03e2a1a/ghc

>---------------------------------------------------------------

commit 8e3410134bd7419db638988d74fcc600b03e2a1a
Author: Ömer Sinan Ağacan <omeragacan at gmail.com>
Date:   Fri Mar 9 15:38:58 2018 +0300

    Fix a debug print in disassembler (#14905)
    
    When interpreter is not profiled (see `interpreterProfiled` in
    `DynFlags`) bytecode generator generates a NULL pointer as the cost
    centre of a `BRK_FUN` instruction:
    
        let cc | interpreterProfiled dflags = cc_arr ! tick_no
               | otherwise = toRemotePtr nullPtr
        let breakInstr = BRK_FUN (fromIntegral tick_no) (getUnique this_mod) cc
        return $ breakInstr `consOL` code
    
    We now take this into account when disassembling `BRK_FUN`.
    
    Reviewers: bgamari, simonmar, erikd
    
    Subscribers: rwbarton, thomie, carter
    
    Differential Revision: https://phabricator.haskell.org/D4490


>---------------------------------------------------------------

8e3410134bd7419db638988d74fcc600b03e2a1a
 rts/Disassembler.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/rts/Disassembler.c b/rts/Disassembler.c
index 8c84e13..01d6c3b 100644
--- a/rts/Disassembler.c
+++ b/rts/Disassembler.c
@@ -68,7 +68,11 @@ disInstr ( StgBCO *bco, int pc )
       case bci_BRK_FUN:
          debugBelch ("BRK_FUN  " );  printPtr( ptrs[instrs[pc]] );
          debugBelch (" %d ", instrs[pc+1]); printPtr( ptrs[instrs[pc+2]] );
-         debugBelch(" %s\n", ((CostCentre*)(literals[instrs[pc+3]]))->label);
+         CostCentre* cc = (CostCentre*)literals[instrs[pc+3]];
+         if (cc) {
+           debugBelch(" %s", cc->label);
+         }
+         debugBelch("\n");
          pc += 4;
          break;
       case bci_SWIZZLE:


From git at git.haskell.org  Sat Mar 10 12:46:52 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Sat, 10 Mar 2018 12:46:52 +0000 (UTC)
Subject: [commit: ghc] master: testsuite: disable T13615 on non-smp targets
 (e3ae0eb)
Message-ID: <20180310124652.1CCD83A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/e3ae0eb8e13adbbbec163d65c3b6e613666c56c9/ghc

>---------------------------------------------------------------

commit e3ae0eb8e13adbbbec163d65c3b6e613666c56c9
Author: Sergei Trofimovich <slyfox at gentoo.org>
Date:   Sat Mar 10 12:33:59 2018 +0000

    testsuite: disable T13615 on non-smp targets
    
    T13615 needs multicore support from RTS:
        T13615: unknown RTS option: -N15
    
    Signed-off-by: Sergei Trofimovich <slyfox at gentoo.org>


>---------------------------------------------------------------

e3ae0eb8e13adbbbec163d65c3b6e613666c56c9
 testsuite/tests/concurrent/T13615/all.T | 1 +
 1 file changed, 1 insertion(+)

diff --git a/testsuite/tests/concurrent/T13615/all.T b/testsuite/tests/concurrent/T13615/all.T
index bac4d01..681f7b0 100644
--- a/testsuite/tests/concurrent/T13615/all.T
+++ b/testsuite/tests/concurrent/T13615/all.T
@@ -1,5 +1,6 @@
 test('T13615',
      [when(fast(), skip),
+      req_smp, # needs -N support
       only_ways(threaded_ways),
       extra_files(['Parallel.hs', 'Memo.hs']),
       # Decrease stack chunk size and lots of capabilities to increase failure


From git at git.haskell.org  Mon Mar 12 07:56:35 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 12 Mar 2018 07:56:35 +0000 (UTC)
Subject: [commit: ghc] master: Remove splitEithers,
 use partitionEithers from base (5c804e5)
Message-ID: <20180312075635.53D3C3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/5c804e5de11c71e84e81c40a10c11baba04b15e1/ghc

>---------------------------------------------------------------

commit 5c804e5de11c71e84e81c40a10c11baba04b15e1
Author: Ömer Sinan Ağacan <omeragacan at gmail.com>
Date:   Mon Mar 12 10:54:17 2018 +0300

    Remove splitEithers, use partitionEithers from base


>---------------------------------------------------------------

5c804e5de11c71e84e81c40a10c11baba04b15e1
 compiler/cmm/Debug.hs           |  5 +++--
 compiler/ghci/ByteCodeGen.hs    |  3 ++-
 compiler/main/DriverPipeline.hs |  5 +++--
 compiler/rename/RnEnv.hs        |  3 ++-
 compiler/utils/Util.hs          | 10 +---------
 5 files changed, 11 insertions(+), 15 deletions(-)

diff --git a/compiler/cmm/Debug.hs b/compiler/cmm/Debug.hs
index c6aae69..044a000 100644
--- a/compiler/cmm/Debug.hs
+++ b/compiler/cmm/Debug.hs
@@ -35,7 +35,7 @@ import Outputable
 import PprCore         ()
 import PprCmmExpr      ( pprExpr )
 import SrcLoc
-import Util
+import Util            ( seqList )
 
 import Hoopl.Block
 import Hoopl.Collections
@@ -46,6 +46,7 @@ import Data.Maybe
 import Data.List     ( minimumBy, nubBy )
 import Data.Ord      ( comparing )
 import qualified Data.Map as Map
+import Data.Either   ( partitionEithers )
 
 -- | Debug information about a block of code. Ticks scope over nested
 -- blocks.
@@ -100,7 +101,7 @@ cmmDebugGen modLoc decls = map (blocksForScope Nothing) topScopes
       -- Analyse tick scope structure: Each one is either a top-level
       -- tick scope, or the child of another.
       (topScopes, childScopes)
-        = splitEithers $ map (\a -> findP a a) $ Map.keys blockCtxs
+        = partitionEithers $ map (\a -> findP a a) $ Map.keys blockCtxs
       findP tsc GlobalScope = Left tsc -- top scope
       findP tsc scp | scp' `Map.member` blockCtxs = Right (scp', tsc)
                     | otherwise                   = findP tsc scp'
diff --git a/compiler/ghci/ByteCodeGen.hs b/compiler/ghci/ByteCodeGen.hs
index 90fcb6d..74168ac 100644
--- a/compiler/ghci/ByteCodeGen.hs
+++ b/compiler/ghci/ByteCodeGen.hs
@@ -73,6 +73,7 @@ import qualified Data.IntMap as IntMap
 import qualified FiniteMap as Map
 import Data.Ord
 import GHC.Stack.CCS
+import Data.Either ( partitionEithers )
 
 -- -----------------------------------------------------------------------------
 -- Generating byte code for a complete module
@@ -89,7 +90,7 @@ byteCodeGen hsc_env this_mod binds tycs mb_modBreaks
                 (const ()) $ do
         -- Split top-level binds into strings and others.
         -- See Note [generating code for top-level string literal bindings].
-        let (strings, flatBinds) = splitEithers $ do
+        let (strings, flatBinds) = partitionEithers $ do
                 (bndr, rhs) <- flattenBinds binds
                 return $ case exprIsTickedString_maybe rhs of
                     Just str -> Left (bndr, str)
diff --git a/compiler/main/DriverPipeline.hs b/compiler/main/DriverPipeline.hs
index 839f6d0..e631cbb 100644
--- a/compiler/main/DriverPipeline.hs
+++ b/compiler/main/DriverPipeline.hs
@@ -73,6 +73,7 @@ import Control.Monad
 import Data.List        ( isSuffixOf, intercalate )
 import Data.Maybe
 import Data.Version
+import Data.Either      ( partitionEithers )
 
 -- ---------------------------------------------------------------------------
 -- Pre-process
@@ -453,7 +454,7 @@ linkingNeeded dflags staticLink linkables pkg_deps = do
         -- first check object files and extra_ld_inputs
         let extra_ld_inputs = [ f | FileOption _ f <- ldInputs dflags ]
         e_extra_times <- mapM (tryIO . getModificationUTCTime) extra_ld_inputs
-        let (errs,extra_times) = splitEithers e_extra_times
+        let (errs,extra_times) = partitionEithers e_extra_times
         let obj_times =  map linkableTime linkables ++ extra_times
         if not (null errs) || any (t <) obj_times
             then return True
@@ -469,7 +470,7 @@ linkingNeeded dflags staticLink linkables pkg_deps = do
         if any isNothing pkg_libfiles then return True else do
         e_lib_times <- mapM (tryIO . getModificationUTCTime)
                           (catMaybes pkg_libfiles)
-        let (lib_errs,lib_times) = splitEithers e_lib_times
+        let (lib_errs,lib_times) = partitionEithers e_lib_times
         if not (null lib_errs) || any (t <) lib_times
            then return True
            else checkLinkInfo dflags pkg_deps exe_file
diff --git a/compiler/rename/RnEnv.hs b/compiler/rename/RnEnv.hs
index 1d9dcfa..600b564 100644
--- a/compiler/rename/RnEnv.hs
+++ b/compiler/rename/RnEnv.hs
@@ -79,6 +79,7 @@ import RnUnbound
 import RnUtils
 import Data.Maybe (isJust)
 import qualified Data.Semigroup as Semi
+import Data.Either      ( partitionEithers )
 
 {-
 *********************************************************
@@ -1436,7 +1437,7 @@ lookupLocalTcNames :: HsSigCtxt -> SDoc -> RdrName -> RnM [(RdrName, Name)]
 -- See Note [Fixity signature lookup]
 lookupLocalTcNames ctxt what rdr_name
   = do { mb_gres <- mapM lookup (dataTcOccs rdr_name)
-       ; let (errs, names) = splitEithers mb_gres
+       ; let (errs, names) = partitionEithers mb_gres
        ; when (null names) $ addErr (head errs) -- Bleat about one only
        ; return names }
   where
diff --git a/compiler/utils/Util.hs b/compiler/utils/Util.hs
index a4520ed..d0a38ec 100644
--- a/compiler/utils/Util.hs
+++ b/compiler/utils/Util.hs
@@ -25,7 +25,7 @@ module Util (
 
         mapFst, mapSnd, chkAppend,
         mapAndUnzip, mapAndUnzip3, mapAccumL2,
-        nOfThem, filterOut, partitionWith, splitEithers,
+        nOfThem, filterOut, partitionWith,
 
         dropWhileEndLE, spanEnd,
 
@@ -296,14 +296,6 @@ partitionWith f (x:xs) = case f x of
                          Right c -> (bs, c:cs)
     where (bs,cs) = partitionWith f xs
 
-splitEithers :: [Either a b] -> ([a], [b])
--- ^ Teases a list of 'Either's apart into two lists
-splitEithers [] = ([],[])
-splitEithers (e : es) = case e of
-                        Left x -> (x:xs, ys)
-                        Right y -> (xs, y:ys)
-    where (xs,ys) = splitEithers es
-
 chkAppend :: [a] -> [a] -> [a]
 -- Checks for the second argument being empty
 -- Used in situations where that situation is common


From git at git.haskell.org  Mon Mar 12 17:02:19 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 12 Mar 2018 17:02:19 +0000 (UTC)
Subject: [commit: ghc] master: Bump Cabal submodule (02b3dad)
Message-ID: <20180312170219.80ED33A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/02b3dad195488c9b0f7457e46319cb3f485570ca/ghc

>---------------------------------------------------------------

commit 02b3dad195488c9b0f7457e46319cb3f485570ca
Author: Ben Gamari <ben at smart-cactus.org>
Date:   Sat Mar 10 13:47:51 2018 -0500

    Bump Cabal submodule


>---------------------------------------------------------------

02b3dad195488c9b0f7457e46319cb3f485570ca
 libraries/Cabal                                         | 2 +-
 testsuite/tests/driver/T4437.hs                         | 2 --
 utils/check-api-annotations/check-api-annotations.cabal | 2 +-
 utils/check-ppr/check-ppr.cabal                         | 2 +-
 utils/ghc-cabal/ghc-cabal.cabal                         | 2 +-
 utils/ghctags/ghctags.cabal                             | 2 +-
 6 files changed, 5 insertions(+), 7 deletions(-)

diff --git a/libraries/Cabal b/libraries/Cabal
index 7ce486e..c219cd3 160000
--- a/libraries/Cabal
+++ b/libraries/Cabal
@@ -1 +1 @@
-Subproject commit 7ce486e6553d24877ae3b23868b95d20bf83760a
+Subproject commit c219cd3f31c8e4e4bc71f93bbcd4de87830a986d
diff --git a/testsuite/tests/driver/T4437.hs b/testsuite/tests/driver/T4437.hs
index 9f892c9..5ae4230 100644
--- a/testsuite/tests/driver/T4437.hs
+++ b/testsuite/tests/driver/T4437.hs
@@ -40,8 +40,6 @@ expectedGhcOnlyExtensions = ["RelaxedLayout",
                              "AlternativeLayoutRule",
                              "AlternativeLayoutRuleTransitional",
                              "EmptyDataDeriving",
-                             "NumericUnderscores",
-                             "BlockArguments",
                              "GeneralisedNewtypeDeriving"]
 
 expectedCabalOnlyExtensions :: [String]
diff --git a/utils/check-api-annotations/check-api-annotations.cabal b/utils/check-api-annotations/check-api-annotations.cabal
index 3cdb378..3a014a6 100644
--- a/utils/check-api-annotations/check-api-annotations.cabal
+++ b/utils/check-api-annotations/check-api-annotations.cabal
@@ -24,6 +24,6 @@ Executable check-api-annotations
 
     Build-Depends: base       >= 4   && < 5,
                    containers,
-                   Cabal      >= 2.2 && < 2.3,
+                   Cabal      >= 2.3 && < 2.4,
                    directory,
                    ghc
diff --git a/utils/check-ppr/check-ppr.cabal b/utils/check-ppr/check-ppr.cabal
index d7429c8..e0d8b9d 100644
--- a/utils/check-ppr/check-ppr.cabal
+++ b/utils/check-ppr/check-ppr.cabal
@@ -25,7 +25,7 @@ Executable check-ppr
     Build-Depends: base       >= 4   && < 5,
                    bytestring,
                    containers,
-                   Cabal      >= 2.2 && < 2.3,
+                   Cabal      >= 2.3 && < 2.4,
                    directory,
                    filepath,
                    ghc
diff --git a/utils/ghc-cabal/ghc-cabal.cabal b/utils/ghc-cabal/ghc-cabal.cabal
index 4b19116..cc0d98d 100644
--- a/utils/ghc-cabal/ghc-cabal.cabal
+++ b/utils/ghc-cabal/ghc-cabal.cabal
@@ -21,7 +21,7 @@ Executable ghc-cabal
 
     Build-Depends: base       >= 3   && < 5,
                    bytestring >= 0.10 && < 0.11,
-                   Cabal      >= 2.2 && < 2.3,
+                   Cabal      >= 2.3 && < 2.4,
                    directory  >= 1.1 && < 1.4,
                    filepath   >= 1.2 && < 1.5
 
diff --git a/utils/ghctags/ghctags.cabal b/utils/ghctags/ghctags.cabal
index c798a93..391eb7a 100644
--- a/utils/ghctags/ghctags.cabal
+++ b/utils/ghctags/ghctags.cabal
@@ -18,6 +18,6 @@ Executable ghctags
 
     Build-Depends: base       >= 4   && < 5,
                    containers,
-                   Cabal      >= 2.2 && <2.3,
+                   Cabal      >= 2.3 && <2.4,
                    ghc
 


From git at git.haskell.org  Tue Mar 13 03:44:53 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 13 Mar 2018 03:44:53 +0000 (UTC)
Subject: [commit: ghc] wip/kavon-nosplit-llvm: addressing a TODO related to
 FFI calls (be00cf3)
Message-ID: <20180313034453.323743A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/kavon-nosplit-llvm
Link       : http://ghc.haskell.org/trac/ghc/changeset/be00cf3a98f256c8cfa56715c187138d586d0118/ghc

>---------------------------------------------------------------

commit be00cf3a98f256c8cfa56715c187138d586d0118
Author: Kavon Farvardin <kavon at farvard.in>
Date:   Sun Mar 11 17:23:34 2018 -0500

    addressing a TODO related to FFI calls


>---------------------------------------------------------------

be00cf3a98f256c8cfa56715c187138d586d0118
 compiler/codeGen/StgCmmForeign.hs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/compiler/codeGen/StgCmmForeign.hs b/compiler/codeGen/StgCmmForeign.hs
index 9666643..8fd2903 100644
--- a/compiler/codeGen/StgCmmForeign.hs
+++ b/compiler/codeGen/StgCmmForeign.hs
@@ -225,7 +225,7 @@ emitForeignCall safety results target args
     target' <- load_target_into_temp target
     args' <- mapM maybe_assign_temp args
     k <- newBlockId
-    let (off, _, copyout) = copyInOflow dflags NativeReturn (Young k) results []
+    let (off, retRegs, copyout) = copyInOflow dflags NativeReturn (Young k) results []
        -- see Note [safe foreign call convention]
     tscope <- getTickScope
     emit $
@@ -241,7 +241,7 @@ emitForeignCall safety results target args
             <*> mkLabel k tscope
             <*> copyout
            )
-    return (ReturnedTo k off []) -- TODO(kavon) this will need to change once you get to foreign calls
+    return (ReturnedTo k off retRegs)
 
 load_target_into_temp :: ForeignTarget -> FCode ForeignTarget
 load_target_into_temp (ForeignTarget expr conv) = do


From git at git.haskell.org  Tue Mar 13 03:44:56 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 13 Mar 2018 03:44:56 +0000 (UTC)
Subject: [commit: ghc] wip/kavon-nosplit-llvm: when compiling a .cmm file,
 carry any ManglerInfo through to the next phase (4790509)
Message-ID: <20180313034456.04CB93A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/kavon-nosplit-llvm
Link       : http://ghc.haskell.org/trac/ghc/changeset/4790509e7b52f5904d50ac937998b47b347fedac/ghc

>---------------------------------------------------------------

commit 4790509e7b52f5904d50ac937998b47b347fedac
Author: Kavon Farvardin <kavon at farvard.in>
Date:   Mon Mar 12 22:43:41 2018 -0500

    when compiling a .cmm file, carry any ManglerInfo through to the next phase


>---------------------------------------------------------------

4790509e7b52f5904d50ac937998b47b347fedac
 compiler/main/DriverPipeline.hs | 8 ++++++--
 compiler/main/HscMain.hs        | 6 +++---
 2 files changed, 9 insertions(+), 5 deletions(-)

diff --git a/compiler/main/DriverPipeline.hs b/compiler/main/DriverPipeline.hs
index acf1d04..902086d 100644
--- a/compiler/main/DriverPipeline.hs
+++ b/compiler/main/DriverPipeline.hs
@@ -1140,9 +1140,13 @@ runPhase (RealPhase Cmm) input_fn dflags
 
         PipeState{hsc_env} <- getPipeState
 
-        liftIO $ hscCompileCmmFile hsc_env input_fn output_fn
+        mangInfo <- liftIO $ hscCompileCmmFile hsc_env input_fn output_fn
         
-        return (RealPhase next_phase, output_fn)
+        let kind = case next_phase of
+                     LlvmOpt -> RealPhaseWithInfo
+                     _       -> \ _ p -> RealPhase p
+
+        return (kind mangInfo next_phase, output_fn)
 
 -----------------------------------------------------------------------------
 -- Cc phase
diff --git a/compiler/main/HscMain.hs b/compiler/main/HscMain.hs
index 6ad0b7c..3dd16f9 100644
--- a/compiler/main/HscMain.hs
+++ b/compiler/main/HscMain.hs
@@ -1392,7 +1392,7 @@ hscInteractive hsc_env cgguts mod_summary = do
 
 ------------------------------
 
-hscCompileCmmFile :: HscEnv -> FilePath -> FilePath -> IO ()
+hscCompileCmmFile :: HscEnv -> FilePath -> FilePath -> IO ManglerInfo
 hscCompileCmmFile hsc_env filename output_filename = runHsc hsc_env $ do
     let dflags = hsc_dflags hsc_env
     cmm <- ioMsgMaybe $ parseCmmFile dflags filename
@@ -1406,9 +1406,9 @@ hscCompileCmmFile hsc_env filename output_filename = runHsc hsc_env $ do
             -- lest we reproduce #11784.
             mod_name = mkModuleName $ "Cmm$" ++ FilePath.takeFileName filename
             cmm_mod = mkModule (thisPackage dflags) mod_name
-        _ <- codeOutput dflags cmm_mod output_filename no_loc NoStubs [] []
+        (_,_,_,info) <- codeOutput dflags cmm_mod output_filename no_loc NoStubs [] []
              rawCmms
-        return ()
+        return info
   where
     no_loc = ModLocation{ ml_hs_file  = Just filename,
                           ml_hi_file  = panic "hscCompileCmmFile: no hi file",


From git at git.haskell.org  Tue Mar 13 04:14:43 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 13 Mar 2018 04:14:43 +0000 (UTC)
Subject: [commit: ghc] wip/angerman/win32-cross: temp fix Makefile (a66332f)
Message-ID: <20180313041443.8A0F63A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/angerman/win32-cross
Link       : http://ghc.haskell.org/trac/ghc/changeset/a66332fdebcf1266f9c0410ef7b3619daf3ef8e7/ghc

>---------------------------------------------------------------

commit a66332fdebcf1266f9c0410ef7b3619daf3ef8e7
Author: Moritz Angermann <moritz.angermann at gmail.com>
Date:   Thu Feb 15 12:29:14 2018 +0800

    temp fix Makefile


>---------------------------------------------------------------

a66332fdebcf1266f9c0410ef7b3619daf3ef8e7
 utils/iserv/Makefile | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/utils/iserv/Makefile b/utils/iserv/Makefile
index f160978..3619858 100644
--- a/utils/iserv/Makefile
+++ b/utils/iserv/Makefile
@@ -10,6 +10,6 @@
 #
 # -----------------------------------------------------------------------------
 
-dir = iserv
-TOP = ..
+dir = utils/iserv
+TOP = ../..
 include $(TOP)/mk/sub-makefile.mk


From git at git.haskell.org  Tue Mar 13 04:14:49 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 13 Mar 2018 04:14:49 +0000 (UTC)
Subject: [commit: ghc] wip/angerman/win32-cross: Adds
 iserv-proxy/cabal.project (a334af8)
Message-ID: <20180313041449.8075D3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/angerman/win32-cross
Link       : http://ghc.haskell.org/trac/ghc/changeset/a334af8e31319b0572c0d8d7f89088bc893ae9c4/ghc

>---------------------------------------------------------------

commit a334af8e31319b0572c0d8d7f89088bc893ae9c4
Author: Moritz Angermann <moritz.angermann at gmail.com>
Date:   Wed Mar 7 11:01:23 2018 +0800

    Adds iserv-proxy/cabal.project


>---------------------------------------------------------------

a334af8e31319b0572c0d8d7f89088bc893ae9c4
 utils/iserv-proxy/cabal.project | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/utils/iserv-proxy/cabal.project b/utils/iserv-proxy/cabal.project
new file mode 100644
index 0000000..2e6cd12
--- /dev/null
+++ b/utils/iserv-proxy/cabal.project
@@ -0,0 +1,4 @@
+packages: . ../../libraries/libiserv
+
+package libiserv
+  flags: +network


From git at git.haskell.org  Tue Mar 13 04:14:46 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 13 Mar 2018 04:14:46 +0000 (UTC)
Subject: [commit: ghc] wip/angerman/win32-cross: adds .gitignore (44ce888)
Message-ID: <20180313041446.5BB313A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/angerman/win32-cross
Link       : http://ghc.haskell.org/trac/ghc/changeset/44ce888e334067d79e14ba3468568950fcc08072/ghc

>---------------------------------------------------------------

commit 44ce888e334067d79e14ba3468568950fcc08072
Author: Moritz Angermann <moritz.angermann at gmail.com>
Date:   Thu Feb 15 13:54:55 2018 +0800

    adds .gitignore


>---------------------------------------------------------------

44ce888e334067d79e14ba3468568950fcc08072
 .gitignore | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/.gitignore b/.gitignore
index efc7a89..a5a36ea 100644
--- a/.gitignore
+++ b/.gitignore
@@ -81,8 +81,7 @@ _darcs/
 /ghc/stage1/
 /ghc/stage2/
 /ghc/stage3/
-/iserv/stage2*/
-/iserv/dist/
+/utils/iserv/stage2*/
 
 # -----------------------------------------------------------------------------
 # specific generated files


From git at git.haskell.org  Tue Mar 13 04:14:53 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 13 Mar 2018 04:14:53 +0000 (UTC)
Subject: [commit: ghc] wip/angerman/win32-cross: Move `iserv` into `utils` and
 change package name from `iserv-bin` to `iserv` (f9bebf5)
Message-ID: <20180313041453.9C5FC3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/angerman/win32-cross
Link       : http://ghc.haskell.org/trac/ghc/changeset/f9bebf53f549216a53fd96f6f803a4501140a24f/ghc

>---------------------------------------------------------------

commit f9bebf53f549216a53fd96f6f803a4501140a24f
Author: Moritz Angermann <moritz.angermann at gmail.com>
Date:   Sat Nov 25 15:10:52 2017 +0800

    Move `iserv` into `utils` and change package name from `iserv-bin` to `iserv`
    
    This is done for consistency. We usually call the package file the same name the
    folder has.  The move into `utils` is done so that we can move the library into
    `libraries/iserv` and the proxy into `utils/iserv-proxy` and then break the
    `iserv.cabal` apart.  This will make building the cross compiler with TH
    simpler, because we can build the library and proxy as separate packages.
    
    # Conflicts:
    #	utils/iserv-proxy/iserv-proxy.cabal


>---------------------------------------------------------------

f9bebf53f549216a53fd96f6f803a4501140a24f
 ghc.mk                                             |  13 +--
 {iserv => libraries/libiserv}/Makefile             |   0
 {iserv => libraries/libiserv}/cbits/iservmain.c    |   0
 libraries/libiserv/ghc.mk                          |   5 +
 libraries/libiserv/libiserv.cabal                  |  39 +++++++
 {iserv => libraries/libiserv}/proxy-src/Remote.hs  |   0
 {iserv => libraries/libiserv}/src/GHCi/Utils.hsc   |   0
 {iserv => libraries/libiserv}/src/Lib.hs           |   0
 {iserv => libraries/libiserv}/src/Main.hs          |   0
 .../libiserv}/src/Remote/Message.hs                |   0
 {iserv => libraries/libiserv}/src/Remote/Slave.hs  |   0
 {iserv => utils/iserv-proxy}/Makefile              |   0
 utils/iserv-proxy/ghc.mk                           | 113 +++++++++++++++++++++
 .../iserv-proxy/iserv-proxy.cabal                  |  72 +------------
 .../Remote.hs => utils/iserv-proxy/src/Main.hs     |   0
 {iserv => utils/iserv}/Makefile                    |   0
 {iserv => utils/iserv}/cbits/iservmain.c           |   0
 {iserv => utils/iserv}/ghc.mk                      |  66 ++++++------
 utils/iserv/iserv.cabal                            |  44 ++++++++
 {iserv => utils/iserv}/src/Main.hs                 |   0
 20 files changed, 246 insertions(+), 106 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc f9bebf53f549216a53fd96f6f803a4501140a24f

From git at git.haskell.org  Tue Mar 13 04:14:56 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 13 Mar 2018 04:14:56 +0000 (UTC)
Subject: [commit: ghc] wip/angerman/win32-cross: Move `iserv` into `utils` and
 change package name from `iserv-bin` to `iserv` (d94a941)
Message-ID: <20180313041456.6F1F43A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/angerman/win32-cross
Link       : http://ghc.haskell.org/trac/ghc/changeset/d94a9418ae6141fb6e4e766d9fbf89fb3a744dc1/ghc

>---------------------------------------------------------------

commit d94a9418ae6141fb6e4e766d9fbf89fb3a744dc1
Author: Moritz Angermann <moritz.angermann at gmail.com>
Date:   Thu Feb 22 16:53:35 2018 +0800

    Move `iserv` into `utils` and change package name from `iserv-bin` to `iserv`
    
    Summary:
    This is done for consistency. We usually call the package file the same name the
    folder has.  The move into `utils` is done so that we can move the library into
    `libraries/iserv` and the proxy into `utils/iserv-proxy` and then break the
    `iserv.cabal` apart.  This will make building the cross compiler with TH
    simpler, because we can build the library and proxy as separate packages.
    
    Test Plan: ./validate
    
    Reviewers: bgamari, goldfire, erikd
    
    Subscribers: rwbarton, thomie, carter
    
    Differential Revision: https://phabricator.haskell.org/D4436


>---------------------------------------------------------------

d94a9418ae6141fb6e4e766d9fbf89fb3a744dc1
 libraries/libiserv/src/Main.hs | 63 ------------------------------------------
 1 file changed, 63 deletions(-)

diff --git a/libraries/libiserv/src/Main.hs b/libraries/libiserv/src/Main.hs
deleted file mode 100644
index 858cee8..0000000
--- a/libraries/libiserv/src/Main.hs
+++ /dev/null
@@ -1,63 +0,0 @@
-{-# LANGUAGE CPP, GADTs #-}
-
--- |
--- The Remote GHCi server.
---
--- For details on Remote GHCi, see Note [Remote GHCi] in
--- compiler/ghci/GHCi.hs.
---
-module Main (main) where
-
-import Lib (serv)
-
-import GHCi.Message
-import GHCi.Signals
-import GHCi.Utils
-
-import Control.Exception
-import Control.Monad
-import Data.IORef
-import System.Environment
-import System.Exit
-import Text.Printf
-
-dieWithUsage :: IO a
-dieWithUsage = do
-    prog <- getProgName
-    die $ prog ++ ": " ++ msg
-  where
-#ifdef WINDOWS
-    msg = "usage: iserv <write-handle> <read-handle> [-v]"
-#else
-    msg = "usage: iserv <write-fd> <read-fd> [-v]"
-#endif
-
-main :: IO ()
-main = do
-  args <- getArgs
-  (wfd1, rfd2, rest) <-
-      case args of
-        arg0:arg1:rest -> do
-            let wfd1 = read arg0
-                rfd2 = read arg1
-            return (wfd1, rfd2, rest)
-        _ -> dieWithUsage
-
-  verbose <- case rest of
-    ["-v"] -> return True
-    []     -> return False
-    _      -> dieWithUsage
-  when verbose $
-    printf "GHC iserv starting (in: %d; out: %d)\n"
-      (fromIntegral rfd2 :: Int) (fromIntegral wfd1 :: Int)
-  inh  <- getGhcHandle rfd2
-  outh <- getGhcHandle wfd1
-  installSignalHandlers
-  lo_ref <- newIORef Nothing
-  let pipe = Pipe{pipeRead = inh, pipeWrite = outh, pipeLeftovers = lo_ref}
-  uninterruptibleMask $ serv verbose hook pipe
-
-  where hook = return -- empty hook
-    -- we cannot allow any async exceptions while communicating, because
-    -- we will lose sync in the protocol, hence uninterruptibleMask.
-


From git at git.haskell.org  Tue Mar 13 04:15:05 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 13 Mar 2018 04:15:05 +0000 (UTC)
Subject: [commit: ghc] wip/angerman/win32-cross: Better logging in
 iserv-remote (7c8ad02)
Message-ID: <20180313041505.AC2483A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/angerman/win32-cross
Link       : http://ghc.haskell.org/trac/ghc/changeset/7c8ad02f4ac5c2ed5508081a1024bcd8a060ef33/ghc

>---------------------------------------------------------------

commit 7c8ad02f4ac5c2ed5508081a1024bcd8a060ef33
Author: Moritz Angermann <moritz.angermann at gmail.com>
Date:   Wed Mar 7 13:38:28 2018 +0800

    Better logging in iserv-remote


>---------------------------------------------------------------

7c8ad02f4ac5c2ed5508081a1024bcd8a060ef33
 libraries/libiserv/src/Remote/Slave.hs | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/libraries/libiserv/src/Remote/Slave.hs b/libraries/libiserv/src/Remote/Slave.hs
index b80d095..9387db1 100644
--- a/libraries/libiserv/src/Remote/Slave.hs
+++ b/libraries/libiserv/src/Remote/Slave.hs
@@ -112,6 +112,7 @@ hook verbose base_path pipe m = case m of
     handleLoad pipe path (base_path <//> path)
     return $ Msg (LoadObj (base_path <//> path))
   Msg (LoadArchive path) -> do
+    when verbose $ putStrLn ("Need Archieve: " ++ path ++ " at " ++ (base_path <//> path))
     handleLoad pipe path (base_path <//> path)
     return $ Msg (LoadArchive (base_path <//> path))
   -- when loading DLLs (.so, .dylib, .dll, ...) and these are provided
@@ -119,7 +120,7 @@ hook verbose base_path pipe m = case m of
   -- therefore we hook the LoadDLL call only for absolute paths to ship the
   -- dll from the host to the target.
   Msg (LoadDLL path) | isAbsolute path -> do
-    when verbose $ putStrLn ("Need DLL: " ++ (base_path <//> path))
+    when verbose $ putStrLn ("Need DLL: " ++ path ++ " at " ++ (base_path <//> path))
     handleLoad pipe path (base_path <//> path)
     return $ Msg (LoadDLL (base_path <//> path))
   _other -> return m


From git at git.haskell.org  Tue Mar 13 04:15:02 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 13 Mar 2018 04:15:02 +0000 (UTC)
Subject: [commit: ghc] wip/angerman/win32-cross: Cleanup LD detection.
 (8aca758)
Message-ID: <20180313041502.C38093A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/angerman/win32-cross
Link       : http://ghc.haskell.org/trac/ghc/changeset/8aca7585d4da0e808fe1947b86f2c301ba050ee6/ghc

>---------------------------------------------------------------

commit 8aca7585d4da0e808fe1947b86f2c301ba050ee6
Author: Moritz Angermann <moritz.angermann at gmail.com>
Date:   Thu Mar 8 11:12:46 2018 +0800

    Cleanup LD detection.


>---------------------------------------------------------------

8aca7585d4da0e808fe1947b86f2c301ba050ee6
 aclocal.m4      | 3 ++-
 mk/config.mk.in | 2 +-
 2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/aclocal.m4 b/aclocal.m4
index 528fd0c..92f542d 100644
--- a/aclocal.m4
+++ b/aclocal.m4
@@ -2362,7 +2362,8 @@ AC_DEFUN([FIND_LD],[
                    FP_CC_LINKER_FLAG_TRY(bfd, $2) ;;
               "GNU gold"*)
                    FP_CC_LINKER_FLAG_TRY(gold, $2)
-                   LD_NO_GOLD=ld
+                   LD_NO_GOLD=
+                   AC_CHECK_TARGET_TOOL([LD_NO_GOLD],[ld])
                    ;;
               "LLD"*)
                    FP_CC_LINKER_FLAG_TRY(lld, $2) ;;
diff --git a/mk/config.mk.in b/mk/config.mk.in
index 92830fa..846857d 100644
--- a/mk/config.mk.in
+++ b/mk/config.mk.in
@@ -537,7 +537,7 @@ AS_STAGE1       = $(AS)
 AS_STAGE2       = $(AS)
 AS_STAGE3       = $(AS)
 
-# why no LD=@LD@ ?
+LD              = @LD@
 LD_STAGE0       = @LD_STAGE0@
 LD_STAGE1       = $(LD)
 LD_STAGE2       = $(LD)


From git at git.haskell.org  Tue Mar 13 04:15:09 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 13 Mar 2018 04:15:09 +0000 (UTC)
Subject: [commit: ghc] wip/angerman/win32-cross: Adds iserv-slave (via CLI)
 (6faf0e6)
Message-ID: <20180313041509.187963A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/angerman/win32-cross
Link       : http://ghc.haskell.org/trac/ghc/changeset/6faf0e6650bc9b8217d541be32f01dc2b092ab8e/ghc

>---------------------------------------------------------------

commit 6faf0e6650bc9b8217d541be32f01dc2b092ab8e
Author: Moritz Angermann <moritz.angermann at gmail.com>
Date:   Wed Mar 7 13:38:09 2018 +0800

    Adds iserv-slave (via CLI)


>---------------------------------------------------------------

6faf0e6650bc9b8217d541be32f01dc2b092ab8e
 utils/{iserv-proxy => iserv-slave}/cabal.project |  0
 utils/iserv-slave/iserv-slave.cabal              | 20 ++++++++++++++++
 utils/iserv-slave/src/Cli.hs                     | 30 ++++++++++++++++++++++++
 3 files changed, 50 insertions(+)

diff --git a/utils/iserv-proxy/cabal.project b/utils/iserv-slave/cabal.project
similarity index 100%
copy from utils/iserv-proxy/cabal.project
copy to utils/iserv-slave/cabal.project
diff --git a/utils/iserv-slave/iserv-slave.cabal b/utils/iserv-slave/iserv-slave.cabal
new file mode 100644
index 0000000..66a2a32
--- /dev/null
+++ b/utils/iserv-slave/iserv-slave.cabal
@@ -0,0 +1,20 @@
+Name: iserv-slave
+Version: 8.5
+Copyright: XXX
+License: BSD3
+-- XXX License-File: LICENSE
+Author: XXX
+Maintainer: XXX
+Synopsis: iserv allows GHC to delegate Tempalte Haskell computations
+Description:
+Category: Development
+build-type: Simple
+cabal-version: >=1.10
+
+Executable iserv-slave
+   Default-Language: Haskell2010
+   Main-Is: Cli.hs
+   Hs-Source-Dirs: src
+   Build-Depends:
+                  base       >= 4   && < 5,
+                  libiserv   == 8.5
diff --git a/utils/iserv-slave/src/Cli.hs b/utils/iserv-slave/src/Cli.hs
new file mode 100644
index 0000000..8a3a34f
--- /dev/null
+++ b/utils/iserv-slave/src/Cli.hs
@@ -0,0 +1,30 @@
+module Main where
+
+import System.Environment (getProgName, getArgs)
+import System.Exit        (die)
+import Remote.Slave       (startSlave')
+
+main :: IO ()
+main = getArgs >>= startSlave
+
+dieWithUsage :: IO a
+dieWithUsage = do
+	prog <- getProgName
+	die $ prog  ++ ": " ++ msg
+  where
+  	msg = "usage: iserv-slave /path/to/storage PORT [-v]"
+
+startSlave :: [String] -> IO ()
+startSlave args0
+	| "--help" `elem` args0 = dieWithUsage
+	| otherwise = do
+		(path, port, rest) <- case args0 of
+			arg0:arg1:rest -> return (arg0, read arg1, rest)
+			_              -> dieWithUsage
+		verbose <- case rest of
+			["-v"] -> return True
+			[]     -> return False
+			_      -> dieWithUsage
+
+		startSlave' verbose path port
+


From git at git.haskell.org  Tue Mar 13 04:14:59 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 13 Mar 2018 04:14:59 +0000 (UTC)
Subject: [commit: ghc] wip/angerman/win32-cross: Rename iserv-slave to
 remote-iserv (d0d02e2)
Message-ID: <20180313041459.E98CF3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/angerman/win32-cross
Link       : http://ghc.haskell.org/trac/ghc/changeset/d0d02e2887ccdc3563661410c5fdc897fa6ba074/ghc

>---------------------------------------------------------------

commit d0d02e2887ccdc3563661410c5fdc897fa6ba074
Author: Moritz Angermann <moritz.angermann at gmail.com>
Date:   Thu Mar 8 14:00:44 2018 +0800

    Rename iserv-slave to remote-iserv


>---------------------------------------------------------------

d0d02e2887ccdc3563661410c5fdc897fa6ba074
 .../.ghc.environment.arm-linux-8.5.20180307        | 31 ++++++++++++++++++++++
 utils/{iserv-slave => remote-iserv}/cabal.project  |  0
 .../remote-iserv.cabal}                            |  7 +++--
 utils/{iserv-slave => remote-iserv}/src/Cli.hs     |  0
 4 files changed, 34 insertions(+), 4 deletions(-)

diff --git a/utils/remote-iserv/.ghc.environment.arm-linux-8.5.20180307 b/utils/remote-iserv/.ghc.environment.arm-linux-8.5.20180307
new file mode 100644
index 0000000..a0a38d3
--- /dev/null
+++ b/utils/remote-iserv/.ghc.environment.arm-linux-8.5.20180307
@@ -0,0 +1,31 @@
+-- This is a GHC environment file written by cabal. This means you can
+-- run ghc or ghci and get the environment of the project as a whole.
+-- But you still need to use cabal repl $target to get the environment
+-- of specific components (libs, exes, tests etc) because each one can
+-- have its own source dirs, cpp flags etc.
+-- 
+clear-package-db
+global-package-db
+package-db /Users/angerman/.cabal/store/ghc-8.5.20180307/package.db
+package-db dist-newstyle/packagedb/ghc-8.5.20180307
+package-id libiserv-8.5-inplace
+package-id base-4.11.0.0
+package-id rts
+package-id ghc-prim-0.5.2.0
+package-id integer-simple-0.1.1.1
+package-id binary-0.8.5.1
+package-id bytestring-0.10.8.2
+package-id deepseq-1.4.3.0
+package-id array-0.5.2.0
+package-id containers-0.5.11.0
+package-id directory-1.3.1.5
+package-id time-1.8.0.2
+package-id filepath-1.4.2
+package-id unix-2.7.2.2
+package-id ghci-8.5
+package-id ghc-boot-8.5
+package-id ghc-boot-th-8.5
+package-id template-haskell-2.13.0.0
+package-id pretty-1.1.3.6
+package-id transformers-0.5.5.0
+package-id ntwrk-2.6.3.4-c7c07d3b
diff --git a/utils/iserv-slave/cabal.project b/utils/remote-iserv/cabal.project
similarity index 100%
rename from utils/iserv-slave/cabal.project
rename to utils/remote-iserv/cabal.project
diff --git a/utils/iserv-slave/iserv-slave.cabal b/utils/remote-iserv/remote-iserv.cabal
similarity index 77%
rename from utils/iserv-slave/iserv-slave.cabal
rename to utils/remote-iserv/remote-iserv.cabal
index 66a2a32..2dc599e 100644
--- a/utils/iserv-slave/iserv-slave.cabal
+++ b/utils/remote-iserv/remote-iserv.cabal
@@ -1,4 +1,4 @@
-Name: iserv-slave
+Name: remote-iserv
 Version: 8.5
 Copyright: XXX
 License: BSD3
@@ -11,10 +11,9 @@ Category: Development
 build-type: Simple
 cabal-version: >=1.10
 
-Executable iserv-slave
+Executable remote-iserv
    Default-Language: Haskell2010
    Main-Is: Cli.hs
    Hs-Source-Dirs: src
-   Build-Depends:
-                  base       >= 4   && < 5,
+   Build-Depends: base       >= 4   && < 5,
                   libiserv   == 8.5
diff --git a/utils/iserv-slave/src/Cli.hs b/utils/remote-iserv/src/Cli.hs
similarity index 100%
rename from utils/iserv-slave/src/Cli.hs
rename to utils/remote-iserv/src/Cli.hs


From git at git.haskell.org  Tue Mar 13 04:15:11 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 13 Mar 2018 04:15:11 +0000 (UTC)
Subject: [commit: ghc] wip/angerman/win32-cross: Assume `C:` to be system
 libraries on windows. (8638eb5)
Message-ID: <20180313041511.D698F3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/angerman/win32-cross
Link       : http://ghc.haskell.org/trac/ghc/changeset/8638eb548c082a11ba3f0967ec223346e19b4031/ghc

>---------------------------------------------------------------

commit 8638eb548c082a11ba3f0967ec223346e19b4031
Author: Moritz Angermann <moritz.angermann at gmail.com>
Date:   Wed Mar 7 13:38:44 2018 +0800

    Assume `C:` to be system libraries on windows.


>---------------------------------------------------------------

8638eb548c082a11ba3f0967ec223346e19b4031
 libraries/libiserv/src/Remote/Slave.hs | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/libraries/libiserv/src/Remote/Slave.hs b/libraries/libiserv/src/Remote/Slave.hs
index 9387db1..701e7d2 100644
--- a/libraries/libiserv/src/Remote/Slave.hs
+++ b/libraries/libiserv/src/Remote/Slave.hs
@@ -119,6 +119,9 @@ hook verbose base_path pipe m = case m of
   -- as relative paths, the intention is to load a pre-existing system library,
   -- therefore we hook the LoadDLL call only for absolute paths to ship the
   -- dll from the host to the target.
+  Msg (LoadDLL path@('C':':':_)) -> do
+    when verbose $ putStrLn ("Need DLL: " ++ path)
+    return $ Msg (LoadDLL path)
   Msg (LoadDLL path) | isAbsolute path -> do
     when verbose $ putStrLn ("Need DLL: " ++ path ++ " at " ++ (base_path <//> path))
     handleLoad pipe path (base_path <//> path)


From git at git.haskell.org  Tue Mar 13 04:15:14 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 13 Mar 2018 04:15:14 +0000 (UTC)
Subject: [commit: ghc] wip/angerman/win32-cross's head updated: Rename
 iserv-slave to remote-iserv (d0d02e2)
Message-ID: <20180313041514.E33D93A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

Branch 'wip/angerman/win32-cross' now includes:

     bf3f0a6 Update Hadrian submodule
     c969c98 driver/utils/dynwrapper.c: Remove unused variable
     be498a2 RTS: Remember to free some pointers
     cb89ba8 RTS: Remove unused retainer schemes
     3d43fd5 Introduce the flag -dsuppress-timestamps to avoid timestamps in dumps.
     5e5e60d boot: Create GNUmakefiles for libraries
     f57c305 testsuite: Bump allocations for T9630
     ffdb110 Update .gitignore
     da4766c circleci: Simplify Hadrian build
     8c1d6b7 Tiny refactor in Core Lint
     40fa420 Comments only
     e99fdf7 Fix a nasty bug in the pure unifier
     d675a35 Better stats for T5837
     3dec923 Test for Trac #13075 is working now
     51e0a38 Comments only
     b2996f1 Fix test for Trac #13075
     df2c3b3 Build quick flavor and run some tests on Windows
     2756117 Revert "Better stats for T5837"
     b8f03bb Cache the fingerprint of sOpt_P
     e261b85 forkProcess: fix task mutex release order
     8dab89b rts: Note functions which must take all_tasks_mutex.
     f8e3cd3 Only load plugins once
     d8e47a2 Make cost centre symbol names deterministic.
     8c7a155 Move Data.Functor.Contravariant from the contravariant package to base.
     e8e9f6a Improve exhaustive checking for guards in pattern bindings and MultiIf.
     125d151 Add regression test for #12790
     aef2b42 Fix #14817 by not double-printing data family instance kind signatures
     4a0d0d8 Various Windows / Cross Compile to Windows fixes
     1773964 DynFlags: Support British spelling of GeneralisedNewtypeDeriving
     969e747 GHCi info: Use src file for cache invalidation
     6a7e159 Improve missing-home-modules warning formatting
     5c28ee8 Add @since annotations for derived instances in base
     6e4fa81 rts/win32: Assert that the IO manager has been initialised
     bc1bcaa configure: Enable LD_NO_GOLD is set in all codepaths
     7782b47 Add Applicative, Semigroup, and Monoid instances in GHC.Generics
     e4dcebf Adds *-cross-ncg flavour.
     6835702 Permit conversion of partially applied PromotedTupleTs
     ffb2738 Fix #14838 by marking TH-spliced code as FromSource
     5f6fcf7 Compile with `--via-asm` when cross compiling.
     44ba60f doCorePass: Expand catch-all
     821daad Correct default -A value in RTS flag usage info
     a2d03c6 Fix the coverage checker's treatment of existential tyvars
     99c556d Parenthesize (() :: Constraint) in argument position
     4631ceb Bump hsc2hs submodule
     8f0b2f5 Bump Cabal submodule to 2.2
     a9f680f Bump Cabal submodule
     e7653bc Wombling around in Trac #14808
     3d25203 Respect Note [The tcType invariant]
     6ee831f Fix #14888 by adding more special cases for ArrowT
     1c062b7 Simplify rnLHsInstType
     df7ac37 Fixup include of gmp/config.mk to use new location
     f6cf400 `--via-asm` only for windows targets
     cf5bc96 add CCX=$(CXX) to integer-gmp
     ee597e9 Schedule.c: remove a redundant CPP guard
     5bc195a Allow top level ticked string literals
     9bccfcd Correct -g flag description
     64c0af7 cmm/: Avoid using lazy left folds
     08345bd Make accumArray and accum stricter
     1488591 Bump nofib submodule
     488d63d Fix interpreter with profiling
     40c4313 Add perf test for #14052
     b120e64 Add bindist-list.uniq to .gitignore
     d9d4632 Schedule.c: remove unreachable code block
     648cb28 Use docker images with non-root user
     b320ba8 Fix a typo about pattern synonyms in documentation.
     b3bfbed Users Guide: Add that --numa is available on Windows too
     43fbb90 Fix typo in description of -V RTS flag
     d99a65a Add -fexternal-dynamic-refs
     98c7749 Revert "GHCi: Don't remove shadowed bindings from typechecker scope."
     bc95fed Error message and doc improvements for #14335
     ed6f9fb ghc-prim: Reduce scope of Clang sync_fetch_and_nand workaround
     94f0254 ghc-prim: Silence -Wsync-nand warning in atomic.c
     47e2a28 Remove outdated documentation bits concerning -Wmissing-methods
     a25b763 configure: Accept suffix in OpenBSD triple's OS name
     df2ea10 Compacted arrays are pinned for isByteArrayPinned#
     dd3906b UNREG: fix implicit declarations from pdep and pext
     8e34101 Fix a debug print in disassembler (#14905)
     e3ae0eb testsuite: disable T13615 on non-smp targets
     5c804e5 Remove splitEithers, use partitionEithers from base
     02b3dad Bump Cabal submodule
     f9bebf5 Move `iserv` into `utils` and change package name from `iserv-bin` to `iserv`
     a66332f temp fix Makefile
     44ce888 adds .gitignore
     d94a941 Move `iserv` into `utils` and change package name from `iserv-bin` to `iserv`
     a334af8 Adds iserv-proxy/cabal.project
     6faf0e6 Adds iserv-slave (via CLI)
     7c8ad02 Better logging in iserv-remote
     8638eb5 Assume `C:` to be system libraries on windows.
     8aca758 Cleanup LD detection.
     d0d02e2 Rename iserv-slave to remote-iserv

From git at git.haskell.org  Tue Mar 13 12:26:52 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 13 Mar 2018 12:26:52 +0000 (UTC)
Subject: [commit: ghc] master: Comment improvements on interpreter breakpoint
 IO action (50972d6)
Message-ID: <20180313122652.E18B83A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/50972d6f7c53d32d324eb5ca96d0a3f8794bdb38/ghc

>---------------------------------------------------------------

commit 50972d6f7c53d32d324eb5ca96d0a3f8794bdb38
Author: Ömer Sinan Ağacan <omeragacan at gmail.com>
Date:   Tue Mar 13 15:25:53 2018 +0300

    Comment improvements on interpreter breakpoint IO action
    
    [skip ci]


>---------------------------------------------------------------

50972d6f7c53d32d324eb5ca96d0a3f8794bdb38
 libraries/ghci/GHCi/Run.hs |  7 ++++++-
 rts/Interpreter.c          | 10 +++++-----
 2 files changed, 11 insertions(+), 6 deletions(-)

diff --git a/libraries/ghci/GHCi/Run.hs b/libraries/ghci/GHCi/Run.hs
index d058775..2988ec2 100644
--- a/libraries/ghci/GHCi/Run.hs
+++ b/libraries/ghci/GHCi/Run.hs
@@ -298,7 +298,12 @@ setStepFlag = poke stepFlag 1
 resetStepFlag :: IO ()
 resetStepFlag = poke stepFlag 0
 
-type BreakpointCallback = Int# -> Int# -> Bool -> HValue -> IO ()
+type BreakpointCallback
+     = Int#    -- the breakpoint index
+    -> Int#    -- the module uniq
+    -> Bool    -- exception?
+    -> HValue  -- the AP_STACK, or exception
+    -> IO ()
 
 foreign import ccall "&rts_breakpoint_io_action"
    breakPointIOAction :: Ptr (StablePtr BreakpointCallback)
diff --git a/rts/Interpreter.c b/rts/Interpreter.c
index 0e80593..9eb6560 100644
--- a/rts/Interpreter.c
+++ b/rts/Interpreter.c
@@ -289,7 +289,7 @@ static StgWord app_ptrs_itbl[] = {
 };
 
 HsStablePtr rts_breakpoint_io_action; // points to the IO action which is executed on a breakpoint
-                                // it is set in main/GHC.hs:runStmt
+                                      // it is set in main/GHC.hs:runStmt
 
 Capability *
 interpretBCO (Capability* cap)
@@ -1098,10 +1098,10 @@ run_BCO:
                   // Arrange the stack to call the breakpoint IO action, and
                   // continue execution of this BCO when the IO action returns.
                   //
-                  // ioAction :: Bool        -- exception?
+                  // ioAction :: Int#        -- the breakpoint index
+                  //          -> Int#        -- the module uniq
+                  //          -> Bool        -- exception?
                   //          -> HValue      -- the AP_STACK, or exception
-                  //          -> Int         -- the breakpoint index (arg2)
-                  //          -> Int         -- the module uniq (arg3)
                   //          -> IO ()
                   //
                   ioAction = (StgClosure *) deRefStablePtr (
@@ -1111,7 +1111,7 @@ run_BCO:
                   SpW(10) = (W_)obj;
                   SpW(9)  = (W_)&stg_apply_interp_info;
                   SpW(8)  = (W_)new_aps;
-                  SpW(7)  = (W_)False_closure;         // True <=> a breakpoint
+                  SpW(7)  = (W_)False_closure;         // True <=> an exception
                   SpW(6)  = (W_)&stg_ap_ppv_info;
                   SpW(5)  = (W_)BCO_LIT(arg3_module_uniq);
                   SpW(4)  = (W_)&stg_ap_n_info;


From git at git.haskell.org  Tue Mar 13 12:58:59 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 13 Mar 2018 12:58:59 +0000 (UTC)
Subject: [commit: ghc] master: Update a comment in Exception.cmm (ba57979)
Message-ID: <20180313125859.C34633A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/ba5797937e575ce6119de6c07703e90dda2557e8/ghc

>---------------------------------------------------------------

commit ba5797937e575ce6119de6c07703e90dda2557e8
Author: Ömer Sinan Ağacan <omeragacan at gmail.com>
Date:   Tue Mar 13 15:34:21 2018 +0300

    Update a comment in Exception.cmm
    
    [skip ci]


>---------------------------------------------------------------

ba5797937e575ce6119de6c07703e90dda2557e8
 rts/Exception.cmm | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/rts/Exception.cmm b/rts/Exception.cmm
index 9661c23..96d95e6 100644
--- a/rts/Exception.cmm
+++ b/rts/Exception.cmm
@@ -532,7 +532,7 @@ retry_pop_stack:
             Sp(8) = exception;
             Sp(7) = stg_raise_ret_info;
             Sp(6) = exception;
-            Sp(5) = ghczmprim_GHCziTypes_True_closure; // True <=> a breakpoint
+            Sp(5) = ghczmprim_GHCziTypes_True_closure; // True <=> an exception
             Sp(4) = stg_ap_ppv_info;
             Sp(3) = 0;
             Sp(2) = stg_ap_n_info;


From git at git.haskell.org  Tue Mar 13 17:38:27 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 13 Mar 2018 17:38:27 +0000 (UTC)
Subject: [commit: ghc] master: Drop GHC 8.0 compatibility (152055a)
Message-ID: <20180313173827.6FD473A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/152055a19cf368439c8450040b68142f8e7d0346/ghc

>---------------------------------------------------------------

commit 152055a19cf368439c8450040b68142f8e7d0346
Author: Ryan Scott <ryan.gl.scott at gmail.com>
Date:   Tue Mar 13 13:36:38 2018 -0400

    Drop GHC 8.0 compatibility
    
    GHC 8.4.1 is out, so now GHC's support window only extends
    back to GHC 8.2. This means we can delete gobs of code that were
    only used for GHC 8.0 support. Hooray!
    
    Test Plan: ./validate
    
    Reviewers: bgamari, erikd, dfeuer
    
    Reviewed By: bgamari, dfeuer
    
    Subscribers: alexbiehl, dfeuer, rwbarton, thomie, carter
    
    Differential Revision: https://phabricator.haskell.org/D4492


>---------------------------------------------------------------

152055a19cf368439c8450040b68142f8e7d0346
 compiler/basicTypes/BasicTypes.hs    |  2 +-
 compiler/basicTypes/Module.hs        |  8 +++-----
 compiler/basicTypes/RdrName.hs       |  2 +-
 compiler/hsSyn/HsExpr.hs             |  2 --
 compiler/main/SysTools/BaseDir.hs    |  4 ----
 compiler/utils/Binary.hs             | 26 --------------------------
 compiler/utils/UniqFM.hs             | 10 +---------
 compiler/utils/UniqMap.hs            |  3 +--
 libraries/ghc-boot/GHC/PackageDb.hs  | 22 ++--------------------
 libraries/ghc-boot/GHC/Serialized.hs |  7 -------
 libraries/ghci/GHCi/Message.hs       |  6 +-----
 libraries/ghci/GHCi/TH/Binary.hs     | 17 -----------------
 testsuite/timeout/WinCBindings.hsc   |  3 ---
 13 files changed, 10 insertions(+), 102 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc 152055a19cf368439c8450040b68142f8e7d0346

From git at git.haskell.org  Tue Mar 13 17:57:31 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 13 Mar 2018 17:57:31 +0000 (UTC)
Subject: [commit: ghc] branch 'wip/D4327' created
Message-ID: <20180313175731.DDD473A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

New branch : wip/D4327
Referencing: adc3415f14aa090c54c68149dcb1d99f19132a83

From git at git.haskell.org  Tue Mar 13 17:57:34 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 13 Mar 2018 17:57:34 +0000 (UTC)
Subject: [commit: ghc] wip/D4327: WIP: Add likelyhood to alternatives from stg
 onwards (adc3415)
Message-ID: <20180313175734.C70BF3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/D4327
Link       : http://ghc.haskell.org/trac/ghc/changeset/adc3415f14aa090c54c68149dcb1d99f19132a83/ghc

>---------------------------------------------------------------

commit adc3415f14aa090c54c68149dcb1d99f19132a83
Author: Andreas Klebinger <klebinger.andreas at gmx.at>
Date:   Tue Mar 13 13:54:53 2018 -0400

    WIP: Add likelyhood to alternatives from stg onwards
    
    Summary:
    Adds a Freq value to Stg/Cmm cases/switches/conditionals.
    
    Currently only generates these values by checking alternatives for
    bottom expressions.
    
    They are passed along to the backend where they affect conditional generation
    slightly.
    
    As it stands runtime improvements seem to be less than expected. This might only be worth merging once we have more branch weights available.
    
    Reviewers: hvr, goldfire, bgamari, simonmar, simonpj, erikd
    
    Reviewed By: simonpj
    
    Subscribers: simonpj, rwbarton, thomie, carter
    
    GHC Trac Issues: #14672
    
    Differential Revision: https://phabricator.haskell.org/D4327


>---------------------------------------------------------------

adc3415f14aa090c54c68149dcb1d99f19132a83
 compiler/basicTypes/BasicTypes.hs       | 107 ++++++++++++++++-
 compiler/basicTypes/MkId.hs             |  18 +--
 compiler/cmm/CmmImplementSwitchPlans.hs |  19 +--
 compiler/cmm/CmmParse.y                 |   9 +-
 compiler/cmm/CmmSwitch.hs               | 201 +++++++++++++++++++++++---------
 compiler/cmm/PprC.hs                    |  10 +-
 compiler/cmm/PprCmm.hs                  |  29 +++--
 compiler/codeGen/StgCmmBind.hs          |   2 +-
 compiler/codeGen/StgCmmExpr.hs          |  49 ++++----
 compiler/codeGen/StgCmmMonad.hs         |   6 +-
 compiler/codeGen/StgCmmPrim.hs          |  28 +++--
 compiler/codeGen/StgCmmProf.hs          |   1 +
 compiler/codeGen/StgCmmUtils.hs         | 118 ++++++++++++-------
 compiler/llvmGen/LlvmCodeGen/CodeGen.hs |  27 ++++-
 compiler/main/DynFlags.hs               |  16 ++-
 compiler/main/ErrUtils.hs               |   9 +-
 compiler/nativeGen/PPC/CodeGen.hs       |   6 +-
 compiler/nativeGen/SPARC/CodeGen.hs     |   6 +-
 compiler/nativeGen/X86/CodeGen.hs       |   6 +-
 compiler/simplStg/StgCse.hs             |  12 +-
 compiler/simplStg/StgStats.hs           |   2 +-
 compiler/simplStg/UnariseStg.hs         |  38 +++---
 compiler/stgSyn/CoreToStg.hs            | 111 ++++++++++--------
 compiler/stgSyn/StgLint.hs              |  12 +-
 compiler/stgSyn/StgSyn.hs               |  14 ++-
 docs/users_guide/debugging.rst          |   9 +-
 docs/users_guide/using-optimisation.rst |  16 +++
 27 files changed, 615 insertions(+), 266 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc adc3415f14aa090c54c68149dcb1d99f19132a83

From git at git.haskell.org  Wed Mar 14 06:17:43 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Wed, 14 Mar 2018 06:17:43 +0000 (UTC)
Subject: [commit: ghc] master: Slighly improve infix con app pattern errors
 (cb6d858)
Message-ID: <20180314061743.C82433A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/cb6d8589c83247ec96d5faa82df3e93f419bbfe0/ghc

>---------------------------------------------------------------

commit cb6d8589c83247ec96d5faa82df3e93f419bbfe0
Author: Ömer Sinan Ağacan <omeragacan at gmail.com>
Date:   Wed Mar 14 09:16:51 2018 +0300

    Slighly improve infix con app pattern errors
    
    Given this program:
    
        main = do
          f $ do
            a <- return 3
              c <- do
              return 5
    
    GHC previously gave this error message:
    
        Main.hs:2:7: error:
            Parse error in pattern: do a <- return 3 c
            Possibly caused by a missing 'do'?
          |
        2 |   f $ do
          |       ^^...
    
    What happened is GHC considered the whole `f $ do a <- return 3 c` as a
    pattern. When parsed as an expression it becomes an infix application of
    `($)`, and GHC checks left and right hand sides before checking if `($)`
    is a valid infix constructor name, and shows the first error it got.
    
    If instead we first check if the infix op is valid in pattern context,
    the error message becomes much clearer:
    
        Main.hs:2:3: error:
            Parse error in pattern: f $ do a <- return 3 c
            Possibly caused by a missing 'do'?
          |
        2 |   f $ do
          |   ^^^^^^...
    
    This may not entirely fix #11188 but I think it's an improvement.
    
    Reviewers: bgamari
    
    Reviewed By: bgamari
    
    Subscribers: rwbarton, thomie, carter
    
    GHC Trac Issues: #11188
    
    Differential Revision: https://phabricator.haskell.org/D4497


>---------------------------------------------------------------

cb6d8589c83247ec96d5faa82df3e93f419bbfe0
 compiler/parser/RdrHsSyn.hs                              | 13 +++++++------
 testsuite/tests/parser/should_fail/InfixAppPatErr.hs     |  5 +++++
 testsuite/tests/parser/should_fail/InfixAppPatErr.stderr |  4 ++++
 testsuite/tests/parser/should_fail/all.T                 |  2 ++
 4 files changed, 18 insertions(+), 6 deletions(-)

diff --git a/compiler/parser/RdrHsSyn.hs b/compiler/parser/RdrHsSyn.hs
index e2943c8..dc35c12 100644
--- a/compiler/parser/RdrHsSyn.hs
+++ b/compiler/parser/RdrHsSyn.hs
@@ -984,12 +984,13 @@ checkAPat msg loc e0 = do
                       | extopt LangExt.NPlusKPatterns opts && (plus == plus_RDR)
                       -> return (mkNPlusKPat (L nloc n) (L lloc lit))
 
-   OpApp l op _fix r  -> do l <- checkLPat msg l
-                            r <- checkLPat msg r
-                            case op of
-                               L cl (HsVar (L _ c)) | isDataOcc (rdrNameOcc c)
-                                      -> return (ConPatIn (L cl c) (InfixCon l r))
-                               _ -> patFail msg loc e0
+   OpApp l (L cl (HsVar (L _ c))) _fix r
+     | isDataOcc (rdrNameOcc c) -> do
+         l <- checkLPat msg l
+         r <- checkLPat msg r
+         return (ConPatIn (L cl c) (InfixCon l r))
+
+   OpApp _l _op _fix _r -> patFail msg loc e0
 
    HsPar e            -> checkLPat msg e >>= (return . ParPat)
    ExplicitList _ _ es  -> do ps <- mapM (checkLPat msg) es
diff --git a/testsuite/tests/parser/should_fail/InfixAppPatErr.hs b/testsuite/tests/parser/should_fail/InfixAppPatErr.hs
new file mode 100644
index 0000000..5a56f71
--- /dev/null
+++ b/testsuite/tests/parser/should_fail/InfixAppPatErr.hs
@@ -0,0 +1,5 @@
+main = do
+  f $ do
+    a <- return 3
+      c <- do
+      return 5
diff --git a/testsuite/tests/parser/should_fail/InfixAppPatErr.stderr b/testsuite/tests/parser/should_fail/InfixAppPatErr.stderr
new file mode 100644
index 0000000..69839e3
--- /dev/null
+++ b/testsuite/tests/parser/should_fail/InfixAppPatErr.stderr
@@ -0,0 +1,4 @@
+
+InfixAppPatErr.hs:2:3: error:
+    Parse error in pattern: f $ do a <- return 3 c
+    Possibly caused by a missing 'do'?
diff --git a/testsuite/tests/parser/should_fail/all.T b/testsuite/tests/parser/should_fail/all.T
index 2cb9c49..d47e0f5 100644
--- a/testsuite/tests/parser/should_fail/all.T
+++ b/testsuite/tests/parser/should_fail/all.T
@@ -115,3 +115,5 @@ test('NumericUnderscoresFail0',
      grep_errmsg(r'^NumericUnderscoresFail0.hs:'), compile_fail, [''])
 test('NumericUnderscoresFail1',
      grep_errmsg(r'^NumericUnderscoresFail1.hs:'), compile_fail, [''])
+
+test('InfixAppPatErr', normal, compile_fail, [''])


From git at git.haskell.org  Sat Mar 17 12:22:47 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Sat, 17 Mar 2018 12:22:47 +0000 (UTC)
Subject: [commit: ghc] master: aclocal.m4: allow more GNU/Hurd tuples (1522cf0)
Message-ID: <20180317122247.80CD73A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/1522cf05c9c3e9afd3ef9c7f3f419460c41488d9/ghc

>---------------------------------------------------------------

commit 1522cf05c9c3e9afd3ef9c7f3f419460c41488d9
Author: Sergei Trofimovich <slyfox at gentoo.org>
Date:   Sat Mar 17 12:12:43 2018 +0000

    aclocal.m4: allow more GNU/Hurd tuples
    
    Running plain ./configure fails on hurd because
    ./config.guess reports unrecognised tuple:
        $ ./config.guess
        i686-unknown-gnu0.9
    
    The change makes the following target configure:
    $ ./configure --target=i686-unknown-gnu0.9
    
    Signed-off-by: Sergei Trofimovich <slyfox at gentoo.org>


>---------------------------------------------------------------

1522cf05c9c3e9afd3ef9c7f3f419460c41488d9
 aclocal.m4 | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/aclocal.m4 b/aclocal.m4
index 528fd0c..04a6bf5 100644
--- a/aclocal.m4
+++ b/aclocal.m4
@@ -1950,6 +1950,9 @@ AC_DEFUN([GHC_CONVERT_VENDOR],[
 # converts os from gnu to ghc naming, and assigns the result to $target_var
 AC_DEFUN([GHC_CONVERT_OS],[
     case "$1" in
+      gnu*) # e.g. i686-unknown-gnu0.9
+        $3="gnu"
+        ;;
       # watchos and tvos are ios variants as of May 2017.
       ios|watchos|tvos)
         $3="ios"
@@ -1964,7 +1967,7 @@ AC_DEFUN([GHC_CONVERT_OS],[
         $3="openbsd"
         ;;
       # As far as I'm aware, none of these have relevant variants
-      freebsd|netbsd|dragonfly|hpux|linuxaout|kfreebsdgnu|freebsd2|solaris2|mingw32|darwin|gnu|nextstep2|nextstep3|sunos4|ultrix|haiku)
+      freebsd|netbsd|dragonfly|hpux|linuxaout|kfreebsdgnu|freebsd2|solaris2|mingw32|darwin|nextstep2|nextstep3|sunos4|ultrix|haiku)
         $3="$1"
         ;;
       aix*) # e.g. powerpc-ibm-aix7.1.3.0


From git at git.haskell.org  Sat Mar 17 17:20:18 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Sat, 17 Mar 2018 17:20:18 +0000 (UTC)
Subject: [commit: ghc] master: aclocal.m4: add OSHurd (debian patch) (0693b0b)
Message-ID: <20180317172018.142D83A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/0693b0b0500236a3dec933350a13f1b0e8c1cb54/ghc

>---------------------------------------------------------------

commit 0693b0b0500236a3dec933350a13f1b0e8c1cb54
Author: Sergei Trofimovich <slyfox at gentoo.org>
Date:   Sat Mar 17 17:12:04 2018 +0000

    aclocal.m4: add OSHurd (debian patch)
    
    ghc treats OSUnknown (and GNU/Hurd) as non-ELF target.
    This causes panic in native codegenerator when trying
    to build PIC code:
    
    ```
      ...
      -- all other platforms
      howToAccessLabel dflags _ _ _ _ _
            | not (positionIndependent dflags)
            = AccessDirectly
            | otherwise
            = panic "howToAccessLabel: PIC not defined for this platform"
    ```
    
    This change declares new 'OSHurd' and marks it as an
    ELF target. Fixes building ghc-stage2 on i686-unknown-gnu0.9.
    
    Patch provided by "Pino" via Samuel Thibault and taken from
    debian.
    
    Signed-off-by: Sergei Trofimovich <slyfox at gentoo.org>


>---------------------------------------------------------------

0693b0b0500236a3dec933350a13f1b0e8c1cb54
 aclocal.m4                 | 5 ++++-
 compiler/utils/Platform.hs | 2 ++
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/aclocal.m4 b/aclocal.m4
index 04a6bf5..58d43e1 100644
--- a/aclocal.m4
+++ b/aclocal.m4
@@ -272,12 +272,15 @@ AC_DEFUN([FPTOOLS_SET_HASKELL_PLATFORM_VARS],
         nto-qnx)
             test -z "[$]2" || eval "[$]2=OSQNXNTO"
             ;;
-        dragonfly|hpux|linuxaout|freebsd2|gnu|nextstep2|nextstep3|sunos4|ultrix)
+        dragonfly|hpux|linuxaout|freebsd2|nextstep2|nextstep3|sunos4|ultrix)
             test -z "[$]2" || eval "[$]2=OSUnknown"
             ;;
         aix)
             test -z "[$]2" || eval "[$]2=OSAIX"
             ;;
+        gnu)
+            test -z "[$]2" || eval "[$]2=OSHurd"
+            ;;
         *)
             echo "Unknown OS '[$]1'"
             exit 1
diff --git a/compiler/utils/Platform.hs b/compiler/utils/Platform.hs
index c313870..449a62a 100644
--- a/compiler/utils/Platform.hs
+++ b/compiler/utils/Platform.hs
@@ -87,6 +87,7 @@ data OS
         | OSHaiku
         | OSQNXNTO
         | OSAIX
+        | OSHurd
         deriving (Read, Show, Eq)
 
 -- | ARM Instruction Set Architecture, Extensions and ABI
@@ -136,6 +137,7 @@ osElfTarget OSKFreeBSD  = True
 osElfTarget OSHaiku     = True
 osElfTarget OSQNXNTO    = False
 osElfTarget OSAIX       = False
+osElfTarget OSHurd      = True
 osElfTarget OSUnknown   = False
  -- Defaulting to False is safe; it means don't rely on any
  -- ELF-specific functionality.  It is important to have a default for


From git at git.haskell.org  Mon Mar 19 00:21:25 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 19 Mar 2018 00:21:25 +0000 (UTC)
Subject: [commit: ghc] branch 'wip/T14068-inline' deleted
Message-ID: <20180319002125.36F143A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

Deleted branch: wip/T14068-inline

From git at git.haskell.org  Mon Mar 19 00:21:27 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 19 Mar 2018 00:21:27 +0000 (UTC)
Subject: [commit: ghc] wip/T14068's head updated: Revert "Prevent inlining of
 loopified programs" (20b00bd)
Message-ID: <20180319002127.6486F3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

Branch 'wip/T14068' now includes:

     20b00bd Revert "Prevent inlining of loopified programs"

From git at git.haskell.org  Mon Mar 19 11:32:45 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 19 Mar 2018 11:32:45 +0000 (UTC)
Subject: [commit: ghc] master: Comments and tiny refactor (2a3702d)
Message-ID: <20180319113245.493413A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/2a3702d8950ebdec27357e08caae3b1cd4f8b00d/ghc

>---------------------------------------------------------------

commit 2a3702d8950ebdec27357e08caae3b1cd4f8b00d
Author: Simon Peyton Jones <simonpj at microsoft.com>
Date:   Mon Mar 19 09:39:58 2018 +0000

    Comments and tiny refactor
    
    Related to Ryan's upcoming patch for Trac #14933


>---------------------------------------------------------------

2a3702d8950ebdec27357e08caae3b1cd4f8b00d
 compiler/iface/IfaceType.hs      |  5 ++++-
 compiler/iface/TcIface.hs        | 18 +++++++++++-------
 compiler/typecheck/TcTypeNats.hs |  9 +++++++++
 compiler/types/TyCoRep.hs        |  9 +++++----
 4 files changed, 29 insertions(+), 12 deletions(-)

diff --git a/compiler/iface/IfaceType.hs b/compiler/iface/IfaceType.hs
index 0c5922e..d0adce9 100644
--- a/compiler/iface/IfaceType.hs
+++ b/compiler/iface/IfaceType.hs
@@ -257,6 +257,10 @@ data IfaceCoercion
   | IfaceForAllCo     IfaceTvBndr IfaceCoercion IfaceCoercion
   | IfaceCoVarCo      IfLclName
   | IfaceAxiomInstCo  IfExtName BranchIndex [IfaceCoercion]
+  | IfaceAxiomRuleCo  IfLclName [IfaceCoercion]
+       -- There are only a fixed number of CoAxiomRules, so it suffices
+       -- to use an IfaceLclName to distinguish them.
+       -- See Note [Adding built-in type families] in TcTypeNats
   | IfaceUnivCo       IfaceUnivCoProv Role IfaceType IfaceType
   | IfaceSymCo        IfaceCoercion
   | IfaceTransCo      IfaceCoercion IfaceCoercion
@@ -266,7 +270,6 @@ data IfaceCoercion
   | IfaceCoherenceCo  IfaceCoercion IfaceCoercion
   | IfaceKindCo       IfaceCoercion
   | IfaceSubCo        IfaceCoercion
-  | IfaceAxiomRuleCo  IfLclName [IfaceCoercion]
   | IfaceFreeCoVar    CoVar    -- See Note [Free tyvars in IfaceType]
   | IfaceHoleCo       CoVar    -- ^ See Note [Holes in IfaceCoercion]
 
diff --git a/compiler/iface/TcIface.hs b/compiler/iface/TcIface.hs
index 70438f6..7d69436 100644
--- a/compiler/iface/TcIface.hs
+++ b/compiler/iface/TcIface.hs
@@ -1359,7 +1359,7 @@ tcIfaceCo = go
                                                <*> go c2
     go (IfaceKindCo c)           = KindCo   <$> go c
     go (IfaceSubCo c)            = SubCo    <$> go c
-    go (IfaceAxiomRuleCo ax cos) = AxiomRuleCo <$> go_axiom_rule ax
+    go (IfaceAxiomRuleCo ax cos) = AxiomRuleCo <$> tcIfaceCoAxiomRule ax
                                                <*> mapM go cos
     go (IfaceFreeCoVar c)        = pprPanic "tcIfaceCo:IfaceFreeCoVar" (ppr c)
     go (IfaceHoleCo c)           = pprPanic "tcIfaceCo:IfaceHoleCo"    (ppr c)
@@ -1367,12 +1367,6 @@ tcIfaceCo = go
     go_var :: FastString -> IfL CoVar
     go_var = tcIfaceLclId
 
-    go_axiom_rule :: FastString -> IfL CoAxiomRule
-    go_axiom_rule n =
-      case Map.lookup n typeNatCoAxiomRules of
-        Just ax -> return ax
-        _  -> pprPanic "go_axiom_rule" (ppr n)
-
 tcIfaceUnivCoProv :: IfaceUnivCoProv -> IfL UnivCoProvenance
 tcIfaceUnivCoProv IfaceUnsafeCoerceProv     = return UnsafeCoerceProv
 tcIfaceUnivCoProv (IfacePhantomProv kco)    = PhantomProv <$> tcIfaceCo kco
@@ -1808,6 +1802,16 @@ tcIfaceCoAxiom :: Name -> IfL (CoAxiom Branched)
 tcIfaceCoAxiom name = do { thing <- tcIfaceImplicit name
                          ; return (tyThingCoAxiom thing) }
 
+
+tcIfaceCoAxiomRule :: IfLclName -> IfL CoAxiomRule
+-- Unlike CoAxioms, which arise form user 'type instance' declarations,
+-- there are a fixed set of CoAxiomRules,
+-- currently enumerated in typeNatCoAxiomRules
+tcIfaceCoAxiomRule n
+  = case Map.lookup n typeNatCoAxiomRules of
+        Just ax -> return ax
+        _  -> pprPanic "go_axiom_rule" (ppr n)
+
 tcIfaceDataCon :: Name -> IfL DataCon
 tcIfaceDataCon name = do { thing <- tcIfaceGlobal name
                          ; case thing of
diff --git a/compiler/typecheck/TcTypeNats.hs b/compiler/typecheck/TcTypeNats.hs
index 78e0b96..139f624 100644
--- a/compiler/typecheck/TcTypeNats.hs
+++ b/compiler/typecheck/TcTypeNats.hs
@@ -1,5 +1,14 @@
 {-# LANGUAGE LambdaCase #-}
 
+{- Note [Type-level natural numbers]
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+See the Wiki page:
+
+    https://ghc.haskell.org/trac/ghc/wiki/TypeNats
+
+and Note [Adding built-in type families]
+-}
+
 module TcTypeNats
   ( typeNatTyCons
   , typeNatCoAxiomRules
diff --git a/compiler/types/TyCoRep.hs b/compiler/types/TyCoRep.hs
index 588963d..cc42599 100644
--- a/compiler/types/TyCoRep.hs
+++ b/compiler/types/TyCoRep.hs
@@ -814,16 +814,17 @@ data Coercion
      -- any left over, we use AppCo.
      -- See [Coercion axioms applied to coercions]
 
+  | AxiomRuleCo CoAxiomRule [Coercion]
+    -- AxiomRuleCo is very like AxiomInstCo, but for a CoAxiomRule
+    -- The number coercions should match exactly the expectations
+    -- of the CoAxiomRule (i.e., the rule is fully saturated).
+
   | UnivCo UnivCoProvenance Role Type Type
       -- :: _ -> "e" -> _ -> _ -> e
 
   | SymCo Coercion             -- :: e -> e
   | TransCo Coercion Coercion  -- :: e -> e -> e
 
-    -- The number coercions should match exactly the expectations
-    -- of the CoAxiomRule (i.e., the rule is fully saturated).
-  | AxiomRuleCo CoAxiomRule [Coercion]
-
   | NthCo  Int         Coercion     -- Zero-indexed; decomposes (T t0 ... tn)
     -- :: _ -> e -> ?? (inverse of TyConAppCo, see Note [TyConAppCo roles])
     -- Using NthCo on a ForAllCo gives an N coercion always


From git at git.haskell.org  Mon Mar 19 12:38:42 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 19 Mar 2018 12:38:42 +0000 (UTC)
Subject: [commit: ghc] ghc-8.4: rel-notes: Fix typo (5a1cfa6)
Message-ID: <20180319123842.CE2743A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : ghc-8.4
Link       : http://ghc.haskell.org/trac/ghc/changeset/5a1cfa650e0af4d87aecd6aa6d9685a5fc021ee6/ghc

>---------------------------------------------------------------

commit 5a1cfa650e0af4d87aecd6aa6d9685a5fc021ee6
Author: Ben Gamari <ben at smart-cactus.org>
Date:   Wed Mar 7 22:17:18 2018 -0500

    rel-notes: Fix typo
    
    Thanks to Gabor for pointing this out.


>---------------------------------------------------------------

5a1cfa650e0af4d87aecd6aa6d9685a5fc021ee6
 docs/users_guide/8.4.1-notes.rst | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/docs/users_guide/8.4.1-notes.rst b/docs/users_guide/8.4.1-notes.rst
index b25d184..182ba07 100644
--- a/docs/users_guide/8.4.1-notes.rst
+++ b/docs/users_guide/8.4.1-notes.rst
@@ -24,7 +24,8 @@ The highlights, since the 8.2.1 release, are:
 
 - Further improvements in code generation
 
-- Incoporation of library changes including the Phase 2 of the Semigroup-Monoid Proposal
+- Incorporation of library changes including the Phase 2 of the Semigroup-Monoid
+  Proposal
 
 - A variety of Windows compatibility improvements
 


From git at git.haskell.org  Mon Mar 19 12:38:45 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 19 Mar 2018 12:38:45 +0000 (UTC)
Subject: [commit: ghc] ghc-8.4: configure: Set RELEASE=NO (e1b2bd0)
Message-ID: <20180319123845.98A463A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : ghc-8.4
Link       : http://ghc.haskell.org/trac/ghc/changeset/e1b2bd01433c07e5ee87185b73b74932127d9248/ghc

>---------------------------------------------------------------

commit e1b2bd01433c07e5ee87185b73b74932127d9248
Author: Ben Gamari <ben at smart-cactus.org>
Date:   Thu Mar 8 14:09:36 2018 -0500

    configure: Set RELEASE=NO


>---------------------------------------------------------------

e1b2bd01433c07e5ee87185b73b74932127d9248
 configure.ac | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/configure.ac b/configure.ac
index 30241a5..77a22b7 100644
--- a/configure.ac
+++ b/configure.ac
@@ -16,7 +16,7 @@ dnl
 AC_INIT([The Glorious Glasgow Haskell Compilation System], [8.4.1], [glasgow-haskell-bugs at haskell.org], [ghc-AC_PACKAGE_VERSION])
 
 # Set this to YES for a released version, otherwise NO
-: ${RELEASE=YES}
+: ${RELEASE=NO}
 
 # The primary version (e.g. 7.5, 7.4.1) is set in the AC_INIT line
 # above.  If this is not a released version, then we will append the


From git at git.haskell.org  Mon Mar 19 12:38:48 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 19 Mar 2018 12:38:48 +0000 (UTC)
Subject: [commit: ghc] ghc-8.4: configure: Accept version suffix in solaris
 name (d7c5ec0)
Message-ID: <20180319123848.6052C3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : ghc-8.4
Link       : http://ghc.haskell.org/trac/ghc/changeset/d7c5ec0c28a45ea22c5901a152cbc9123a07564c/ghc

>---------------------------------------------------------------

commit d7c5ec0c28a45ea22c5901a152cbc9123a07564c
Author: Ben Gamari <ben at smart-cactus.org>
Date:   Thu Mar 8 15:26:09 2018 -0500

    configure: Accept version suffix in solaris name
    
    OpenIndiana apparently reports a triple of i386-pc-solaris2.11.


>---------------------------------------------------------------

d7c5ec0c28a45ea22c5901a152cbc9123a07564c
 aclocal.m4 | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/aclocal.m4 b/aclocal.m4
index c02c1d1..91cdd40 100644
--- a/aclocal.m4
+++ b/aclocal.m4
@@ -1976,7 +1976,7 @@ AC_DEFUN([GHC_CONVERT_OS],[
         $3="linux"
         ;;
       # As far as I'm aware, none of these have relevant variants
-      freebsd|netbsd|openbsd|dragonfly|hpux|linuxaout|kfreebsdgnu|freebsd2|solaris2|mingw32|darwin|gnu|nextstep2|nextstep3|sunos4|ultrix|haiku)
+      freebsd|netbsd|openbsd|dragonfly|hpux|linuxaout|kfreebsdgnu|freebsd2|mingw32|darwin|gnu|nextstep2|nextstep3|sunos4|ultrix|haiku)
         $3="$1"
         ;;
       aix*) # e.g. powerpc-ibm-aix7.1.3.0
@@ -1985,6 +1985,9 @@ AC_DEFUN([GHC_CONVERT_OS],[
       darwin*) # e.g. aarch64-apple-darwin14
         $3="darwin"
         ;;
+      solaris2*)
+        $3="solaris2"
+        ;;
       freebsd*) # like i686-gentoo-freebsd7
                 #      i686-gentoo-freebsd8
                 #      i686-gentoo-freebsd8.2


From git at git.haskell.org  Mon Mar 19 12:49:11 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 19 Mar 2018 12:49:11 +0000 (UTC)
Subject: [commit: ghc] master: Update test for #5129: (5a1ad23)
Message-ID: <20180319124911.B4A603A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/5a1ad231fc871f27f2811ae46285a79573d8dfae/ghc

>---------------------------------------------------------------

commit 5a1ad231fc871f27f2811ae46285a79573d8dfae
Author: Ömer Sinan Ağacan <omeragacan at gmail.com>
Date:   Mon Mar 19 15:46:44 2018 +0300

    Update test for #5129:
    
    Make sure it runs with --fast validate with correct optimisation
    settings (-O1 or above) so that it actually tests the bug.
    
    Because the bug is in the simplifier running it with -O0 doesn't
    test it.


>---------------------------------------------------------------

5a1ad231fc871f27f2811ae46285a79573d8dfae
 testsuite/tests/codeGen/should_run/all.T | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/testsuite/tests/codeGen/should_run/all.T b/testsuite/tests/codeGen/should_run/all.T
index 9403c4b..cf4904e 100644
--- a/testsuite/tests/codeGen/should_run/all.T
+++ b/testsuite/tests/codeGen/should_run/all.T
@@ -90,7 +90,13 @@ test('T3677', extra_run_opts('+RTS -K8k -RTS'), compile_and_run, [''])
 test('T4441', normal, compile_and_run, [''])
 test('T5149', omit_ways(['ghci']), multi_compile_and_run,
                  ['T5149', [('T5149_cmm.cmm', '')], ''])
-test('T5129', normal, compile_and_run, [''])
+
+test('T5129',
+     # The bug is in simplifier when run with -O1 and above, so only run it
+     # optimised, using any backend.
+     [ only_ways(['optasm']), expect_broken(5129) ],
+     compile_and_run, [''])
+
 test('T5626', exit_code(1), compile_and_run, [''])
 test('T5747', when(arch('i386'), extra_hc_opts('-msse2')), compile_and_run, ['-O2'])
 test('T5785', normal, compile_and_run, [''])


From git at git.haskell.org  Mon Mar 19 12:51:57 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 19 Mar 2018 12:51:57 +0000 (UTC)
Subject: [commit: ghc] : Set RELEASE=YES, version 8.4.1 (f31c40e)
Message-ID: <20180319125157.B14633A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : 
Link       : http://ghc.haskell.org/trac/ghc/changeset/f31c40efdc918bc9da8a325327ba5a472bd6ea9e/ghc

>---------------------------------------------------------------

commit f31c40efdc918bc9da8a325327ba5a472bd6ea9e
Author: Ben Gamari <ben at smart-cactus.org>
Date:   Sun Mar 4 13:53:54 2018 -0500

    Set RELEASE=YES, version 8.4.1


>---------------------------------------------------------------

f31c40efdc918bc9da8a325327ba5a472bd6ea9e
 configure.ac | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/configure.ac b/configure.ac
index 57d76b4..30241a5 100644
--- a/configure.ac
+++ b/configure.ac
@@ -13,10 +13,10 @@ dnl
 # see what flags are available. (Better yet, read the documentation!)
 #
 
-AC_INIT([The Glorious Glasgow Haskell Compilation System], [8.4.0], [glasgow-haskell-bugs at haskell.org], [ghc-AC_PACKAGE_VERSION])
+AC_INIT([The Glorious Glasgow Haskell Compilation System], [8.4.1], [glasgow-haskell-bugs at haskell.org], [ghc-AC_PACKAGE_VERSION])
 
 # Set this to YES for a released version, otherwise NO
-: ${RELEASE=NO}
+: ${RELEASE=YES}
 
 # The primary version (e.g. 7.5, 7.4.1) is set in the AC_INIT line
 # above.  If this is not a released version, then we will append the


From git at git.haskell.org  Mon Mar 19 16:37:20 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 19 Mar 2018 16:37:20 +0000 (UTC)
Subject: [commit: ghc] master: Add a build with 32bit Ubuntu container
 (f9a6d42)
Message-ID: <20180319163720.669CA3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/f9a6d4207fb0e551821fee847ac064ac31d96bba/ghc

>---------------------------------------------------------------

commit f9a6d4207fb0e551821fee847ac064ac31d96bba
Author: mrkkrp <markkarpov92 at gmail.com>
Date:   Wed Feb 28 18:18:58 2018 +0700

    Add a build with 32bit Ubuntu container


>---------------------------------------------------------------

f9a6d4207fb0e551821fee847ac064ac31d96bba
 .circleci/config.yml                   | 24 ++++++++++++++++++++++++
 .circleci/images/i386-linux/Dockerfile | 30 ++++++++++++++++++++++++++++++
 2 files changed, 54 insertions(+)

diff --git a/.circleci/config.yml b/.circleci/config.yml
index b4a9947..2868f8d 100644
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -31,6 +31,11 @@ aliases:
     run:
       name: Configure
       command: ./configure
+  - &configure_unix_32
+    run:
+      name: Configure
+      command: |
+        setarch i386 ./configure --with-ghc=/opt/ghc-i386/8.2.2/bin/ghc
   - &configure_bsd
     run:
       name: Configure
@@ -207,6 +212,24 @@ jobs:
       - *make
       - *test
 
+  "validate-i386-linux":
+    resource_class: xlarge
+    docker:
+      - image: mrkkrp/ghcci-i386-linux:0.0.1
+    environment:
+      <<: *buildenv
+    steps:
+      - checkout
+      - *prepare
+      - *submodules
+      - *boot
+      - *configure_unix_32
+      - *make
+      - *test
+      - *bindist
+      - *collectartifacts
+      - *storeartifacts
+
 workflows:
   version: 2
   validate:
@@ -216,6 +239,7 @@ workflows:
     # - validate-x86_64-freebsd
     - validate-x86_64-darwin
     - validate-x86_64-linux-llvm
+    - validate-i386-linux
     - validate-hadrian-x86_64-linux
 
   nightly:
diff --git a/.circleci/images/i386-linux/Dockerfile b/.circleci/images/i386-linux/Dockerfile
new file mode 100644
index 0000000..7d3e968
--- /dev/null
+++ b/.circleci/images/i386-linux/Dockerfile
@@ -0,0 +1,30 @@
+# This Dockerfile tries to replicate haskell:8.2 a bit, but it does so on
+# top of i368/debian:jessie instead of debian:jessie because I had troubles
+# making i386 GHC bindist working there.
+
+FROM i386/debian:jessie
+
+ENV LANG C.UTF-8
+
+# Install the necessary packages, including HVR stuff.
+RUN echo 'deb http://ppa.launchpad.net/hvr/ghc/ubuntu trusty main' > /etc/apt/sources.list.d/ghc.list
+RUN apt-key adv --keyserver keyserver.ubuntu.com --recv-keys F6F88286
+RUN apt-get update -qq
+RUN apt-get install -qy git make automake autoconf gcc perl python3 texinfo xz-utils lbzip2 bzip2 patch openssh-client sudo curl zlib1g-dev libtinfo-dev libsqlite3-0 libsqlite3-dev ca-certificates g++ cabal-install-2.0 ghc-8.2.2 happy-1.19.5 alex-3.1.7
+ENV PATH /opt/cabal/2.0/bin:/opt/ghc/8.2.2/bin:/opt/happy/1.19.5/bin:/opt/alex/3.1.7/bin:$PATH
+
+# Get i386 GHC bindist for 32 bit CI builds.
+RUN cd /tmp && curl https://downloads.haskell.org/~ghc/8.2.2/ghc-8.2.2-i386-deb8-linux.tar.xz | tar -Jx
+RUN cd /tmp/ghc-8.2.2 && setarch i386 ./configure --prefix=/opt/ghc-i386/8.2.2 CFLAGS=-m32 --target=i386-unknown-linux --build=i386-unknown-linux --host=i386-unknown-linux
+RUN cd /tmp/ghc-8.2.2 && make install
+RUN rm -rf /tmp/ghc-8.2.2
+ENV PATH /opt/ghc-i386/8.2.2/bin:$PATH
+
+# Create a normal user.
+RUN adduser ghc --gecos "GHC builds" --disabled-password
+RUN echo "ghc ALL = NOPASSWD : ALL" > /etc/sudoers.d/ghc
+USER ghc
+
+WORKDIR /home/ghc/
+
+CMD ["bash"]


From git at git.haskell.org  Mon Mar 19 16:37:34 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 19 Mar 2018 16:37:34 +0000 (UTC)
Subject: [commit: ghc] master: rts: Add --internal-counters RTS flag and
 several counters (2918abf)
Message-ID: <20180319163734.A07613A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/2918abf75594001deed51ee252a05b146f844489/ghc

>---------------------------------------------------------------

commit 2918abf75594001deed51ee252a05b146f844489
Author: Douglas Wilson <douglas.wilson at gmail.com>
Date:   Mon Mar 19 11:55:37 2018 -0400

    rts: Add --internal-counters RTS flag and several counters
    
    The existing internal counters:
    * gc_alloc_block_sync
    * whitehole_spin
    * gen[g].sync
    * gen[1].sync
    
    are now not shown in the -s report unless --internal-counters is also passed.
    
    If --internal-counters is passed we now show the counters above, reformatted, as
    well as several other counters. In particular, we now count the yieldThread()
    calls that SpinLocks do as well as their spins.
    
    The added counters are:
    * gc_spin (spin and yield)
    * mut_spin (spin and yield)
    * whitehole_threadPaused (spin only)
    * whitehole_executeMessage (spin only)
    * whitehole_lockClosure (spin only)
    * waitForGcThreadsd (spin and yield)
    
    As well as the following, which are not SpinLock-like things:
    * any_work
    * do_work
    * scav_find_work
    
    See the Note for descriptions of what these counters are.
    
    We add busy_wait_nops in these loops along with the counter increment where it
    was absent.
    
    Old internal counters output:
    ```
    gc_alloc_block_sync: 0
    whitehole_gc_spin: 0
    gen[0].sync: 0
    gen[1].sync: 0
    ```
    
    New internal counters output:
    ```
    Internal Counters:
                                               Spins        Yields
        gc_alloc_block_sync                      323             0
        gc_spin                              9016713           752
        mut_spin                            57360944         47716
        whitehole_gc                               0           n/a
        whitehole_threadPaused                     0           n/a
        whitehole_executeMessage                   0           n/a
        whitehole_lockClosure                      0             0
        waitForGcThreads                           2           415
        gen[0].sync                                6             0
        gen[1].sync                                1             0
    
        any_work                                2017
        no_work                                 2014
        scav_find_work                          1004
    ```
    
    Test Plan:
    ./validate
    
    Check it builds with #define PROF_SPIN removed from includes/rts/Config.h
    
    Reviewers: bgamari, erikd, simonmar, hvr
    
    Reviewed By: simonmar
    
    Subscribers: rwbarton, thomie, carter
    
    GHC Trac Issues: #3553, #9221
    
    Differential Revision: https://phabricator.haskell.org/D4302


>---------------------------------------------------------------

2918abf75594001deed51ee252a05b146f844489
 docs/users_guide/runtime_control.rst        |   6 +-
 includes/RtsAPI.h                           |  24 ++++
 includes/rts/Flags.h                        |   1 +
 includes/rts/SpinLock.h                     |   5 +-
 includes/rts/storage/GC.h                   |   2 +-
 libraries/base/GHC/RTS/Flags.hsc            |   3 +
 rts/Messages.c                              |   3 +
 rts/Messages.h                              |   4 +
 rts/RtsFlags.c                              |   6 +
 rts/SMPClosureOps.h                         |  12 ++
 rts/Stats.c                                 | 189 ++++++++++++++++++++++++++--
 rts/Stats.h                                 |   5 +-
 rts/StgMiscClosures.cmm                     |  10 ++
 rts/ThreadPaused.c                          |   4 +
 rts/ThreadPaused.h                          |   8 ++
 rts/sm/Evac.c                               |   9 +-
 rts/sm/GC.c                                 |  71 ++++++++---
 rts/sm/GC.h                                 |   2 +
 testsuite/tests/rts/InternalCounters.stdout |   1 +
 testsuite/tests/rts/Makefile                |  19 +--
 testsuite/tests/rts/all.T                   |   2 +
 21 files changed, 346 insertions(+), 40 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc 2918abf75594001deed51ee252a05b146f844489

From git at git.haskell.org  Mon Mar 19 16:37:47 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 19 Mar 2018 16:37:47 +0000 (UTC)
Subject: [commit: ghc] master: Also check local rules with -frules-check
 (3d378d9)
Message-ID: <20180319163747.EE11B3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/3d378d983a28d3650220180e1524c63fb2f4c747/ghc

>---------------------------------------------------------------

commit 3d378d983a28d3650220180e1524c63fb2f4c747
Author: Matthew Pickering <matthewtpickering at gmail.com>
Date:   Mon Mar 19 11:57:06 2018 -0400

    Also check local rules with -frules-check
    
    Reviewers: bgamari
    
    Reviewed By: bgamari
    
    Subscribers: rwbarton, thomie, carter
    
    Differential Revision: https://phabricator.haskell.org/D4255


>---------------------------------------------------------------

3d378d983a28d3650220180e1524c63fb2f4c747
 compiler/simplCore/SimplCore.hs |  7 +++++--
 compiler/specialise/Rules.hs    | 10 +++++-----
 2 files changed, 10 insertions(+), 7 deletions(-)

diff --git a/compiler/simplCore/SimplCore.hs b/compiler/simplCore/SimplCore.hs
index 0a20eb0..bf69964 100644
--- a/compiler/simplCore/SimplCore.hs
+++ b/compiler/simplCore/SimplCore.hs
@@ -17,7 +17,8 @@ import CoreSyn
 import HscTypes
 import CSE              ( cseProgram )
 import Rules            ( mkRuleBase, unionRuleBase,
-                          extendRuleBaseList, ruleCheckProgram, addRuleInfo, )
+                          extendRuleBaseList, ruleCheckProgram, addRuleInfo,
+                          getRules )
 import PprCore          ( pprCoreBindings, pprCoreExpr )
 import OccurAnal        ( occurAnalysePgm, occurAnalyseExpr )
 import IdInfo
@@ -516,10 +517,12 @@ ruleCheckPass current_phase pat guts =
     { rb <- getRuleBase
     ; dflags <- getDynFlags
     ; vis_orphs <- getVisibleOrphanMods
+    ; let rule_fn fn = getRules (RuleEnv rb vis_orphs) fn
+                        ++ (mg_rules guts)
     ; liftIO $ putLogMsg dflags NoReason Err.SevDump noSrcSpan
                    (defaultDumpStyle dflags)
                    (ruleCheckProgram current_phase pat
-                      (RuleEnv rb vis_orphs) (mg_binds guts))
+                      rule_fn (mg_binds guts))
     ; return guts }
 
 doPassDUM :: (DynFlags -> UniqSupply -> CoreProgram -> IO CoreProgram) -> ModGuts -> CoreM ModGuts
diff --git a/compiler/specialise/Rules.hs b/compiler/specialise/Rules.hs
index 319404e..b602595 100644
--- a/compiler/specialise/Rules.hs
+++ b/compiler/specialise/Rules.hs
@@ -1148,10 +1148,10 @@ is so important.
 -- string for the purposes of error reporting
 ruleCheckProgram :: CompilerPhase               -- ^ Rule activation test
                  -> String                      -- ^ Rule pattern
-                 -> RuleEnv                     -- ^ Database of rules
+                 -> (Id -> [CoreRule])          -- ^ Rules for an Id
                  -> CoreProgram                 -- ^ Bindings to check in
                  -> SDoc                        -- ^ Resulting check message
-ruleCheckProgram phase rule_pat rule_base binds
+ruleCheckProgram phase rule_pat rules binds
   | isEmptyBag results
   = text "Rule check results: no rule application sites"
   | otherwise
@@ -1164,7 +1164,7 @@ ruleCheckProgram phase rule_pat rule_base binds
                        , rc_id_unf    = idUnfolding     -- Not quite right
                                                         -- Should use activeUnfolding
                        , rc_pattern   = rule_pat
-                       , rc_rule_base = rule_base }
+                       , rc_rules = rules }
     results = unionManyBags (map (ruleCheckBind env) binds)
     line = text (replicate 20 '-')
 
@@ -1172,7 +1172,7 @@ data RuleCheckEnv = RuleCheckEnv {
     rc_is_active :: Activation -> Bool,
     rc_id_unf  :: IdUnfoldingFun,
     rc_pattern :: String,
-    rc_rule_base :: RuleEnv
+    rc_rules :: Id -> [CoreRule]
 }
 
 ruleCheckBind :: RuleCheckEnv -> CoreBind -> Bag SDoc
@@ -1206,7 +1206,7 @@ ruleCheckFun env fn args
   | null name_match_rules = emptyBag
   | otherwise             = unitBag (ruleAppCheck_help env fn args name_match_rules)
   where
-    name_match_rules = filter match (getRules (rc_rule_base env) fn)
+    name_match_rules = filter match (rc_rules env fn)
     match rule = (rc_pattern env) `isPrefixOf` unpackFS (ruleName rule)
 
 ruleAppCheck_help :: RuleCheckEnv -> Id -> [CoreExpr] -> [CoreRule] -> SDoc


From git at git.haskell.org  Mon Mar 19 16:38:01 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 19 Mar 2018 16:38:01 +0000 (UTC)
Subject: [commit: ghc] master: Be more selective in which conditionals we
 invert (39c7406)
Message-ID: <20180319163801.48CDF3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/39c740636dfc7ce4b5590fa60adc6d5ecf5a79b6/ghc

>---------------------------------------------------------------

commit 39c740636dfc7ce4b5590fa60adc6d5ecf5a79b6
Author: Simon Marlow <marlowsd at gmail.com>
Date:   Mon Mar 19 11:57:27 2018 -0400

    Be more selective in which conditionals we invert
    
    Test Plan: validate
    
    Reviewers: bgamari, AndreasK, erikd
    
    Reviewed By: AndreasK
    
    Subscribers: rwbarton, thomie, carter
    
    Differential Revision: https://phabricator.haskell.org/D4398


>---------------------------------------------------------------

39c740636dfc7ce4b5590fa60adc6d5ecf5a79b6
 compiler/cmm/CmmOpt.hs   |  8 -------
 compiler/cmm/CmmSink.hs  | 55 +++++++++++++++++++++++++++++-------------------
 compiler/cmm/CmmUtils.hs | 10 ++++++++-
 3 files changed, 42 insertions(+), 31 deletions(-)

diff --git a/compiler/cmm/CmmOpt.hs b/compiler/cmm/CmmOpt.hs
index 6b4d792..e837d29 100644
--- a/compiler/cmm/CmmOpt.hs
+++ b/compiler/cmm/CmmOpt.hs
@@ -422,14 +422,6 @@ That's what the constant-folding operations on comparison operators do above.
 -- -----------------------------------------------------------------------------
 -- Utils
 
-isLit :: CmmExpr -> Bool
-isLit (CmmLit _) = True
-isLit _          = False
-
-isComparisonExpr :: CmmExpr -> Bool
-isComparisonExpr (CmmMachOp op _) = isComparisonMachOp op
-isComparisonExpr _                  = False
-
 isPicReg :: CmmExpr -> Bool
 isPicReg (CmmReg (CmmGlobal PicBaseReg)) = True
 isPicReg _ = False
diff --git a/compiler/cmm/CmmSink.hs b/compiler/cmm/CmmSink.hs
index 487f0bc..c939736 100644
--- a/compiler/cmm/CmmSink.hs
+++ b/compiler/cmm/CmmSink.hs
@@ -458,17 +458,7 @@ tryToInline dflags live node assigs = go usages node emptyLRegSet assigs
         occurs_once = not l_live && l_usages == Just 1
         occurs_none = not l_live && l_usages == Nothing
 
-        inl_node = case mapExpDeep inl_exp node of
-                     -- See Note [Improving conditionals]
-                     CmmCondBranch (CmmMachOp (MO_Ne w) args)
-                                   ti fi l
-                           -> CmmCondBranch (cmmMachOpFold dflags (MO_Eq w) args)
-                                            fi ti (inv_likeliness l)
-                     node' -> node'
-
-        inv_likeliness :: Maybe Bool -> Maybe Bool
-        inv_likeliness Nothing  = Nothing
-        inv_likeliness (Just l) = Just (not l)
+        inl_node = improveConditional (mapExpDeep inl_exp node)
 
         inl_exp :: CmmExpr -> CmmExpr
         -- inl_exp is where the inlining actually takes place!
@@ -479,22 +469,43 @@ tryToInline dflags live node assigs = go usages node emptyLRegSet assigs
         inl_exp (CmmMachOp op args) = cmmMachOpFold dflags op args
         inl_exp other = other
 
-{- Note [Improving conditionals]
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-Given
-  CmmCondBranch ((a >## b) != 1) t f
-where a,b, are Floats, the constant folder /cannot/ turn it into
-  CmmCondBranch (a <=## b) t f
-because comparison on floats are not invertible
-(see CmmMachOp.maybeInvertComparison).
 
-What we want instead is simply to reverse the true/false branches thus
+{- Note [improveConditional]
+
+cmmMachOpFold tries to simplify conditionals to turn things like
+  (a == b) != 1
+into
+  (a != b)
+but there's one case it can't handle: when the comparison is over
+floating-point values, we can't invert it, because floating-point
+comparisions aren't invertible (because NaN).
+
+But we *can* optimise this conditional by swapping the true and false
+branches. Given
   CmmCondBranch ((a >## b) != 1) t f
--->
+we can turn it into
   CmmCondBranch (a >## b) f t
 
-And we do that right here in tryToInline, just as we do cmmMachOpFold.
+So here we catch conditionals that weren't optimised by cmmMachOpFold,
+and apply above transformation to eliminate the comparison against 1.
+
+It's tempting to just turn every != into == and then let cmmMachOpFold
+do its thing, but that risks changing a nice fall-through conditional
+into one that requires two jumps. (see swapcond_last in
+CmmContFlowOpt), so instead we carefully look for just the cases where
+we can eliminate a comparison.
 -}
+improveConditional :: CmmNode O x -> CmmNode O x
+improveConditional
+  (CmmCondBranch (CmmMachOp mop [x, CmmLit (CmmInt 1 _)]) t f l)
+  | neLike mop, isComparisonExpr x
+  = CmmCondBranch x f t (fmap not l)
+  where
+    neLike (MO_Ne _) = True
+    neLike (MO_U_Lt _) = True   -- (x<y) < 1 behaves like (x<y) != 1
+    neLike (MO_S_Lt _) = True   -- (x<y) < 1 behaves like (x<y) != 1
+    neLike _ = False
+improveConditional other = other
 
 -- Note [dependent assignments]
 -- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
diff --git a/compiler/cmm/CmmUtils.hs b/compiler/cmm/CmmUtils.hs
index 4a1d874..fcd0ec5 100644
--- a/compiler/cmm/CmmUtils.hs
+++ b/compiler/cmm/CmmUtils.hs
@@ -35,7 +35,7 @@ module CmmUtils(
         cmmSubWord, cmmAddWord, cmmMulWord, cmmQuotWord,
         cmmToWord,
 
-        isTrivialCmmExpr, hasNoGlobalRegs,
+        isTrivialCmmExpr, hasNoGlobalRegs, isLit, isComparisonExpr,
 
         baseExpr, spExpr, hpExpr, spLimExpr, hpLimExpr,
         currentTSOExpr, currentNurseryExpr, cccsExpr,
@@ -389,6 +389,14 @@ hasNoGlobalRegs (CmmReg (CmmLocal _))      = True
 hasNoGlobalRegs (CmmRegOff (CmmLocal _) _) = True
 hasNoGlobalRegs _ = False
 
+isLit :: CmmExpr -> Bool
+isLit (CmmLit _) = True
+isLit _          = False
+
+isComparisonExpr :: CmmExpr -> Bool
+isComparisonExpr (CmmMachOp op _) = isComparisonMachOp op
+isComparisonExpr _                  = False
+
 ---------------------------------------------------
 --
 --      Tagging


From git at git.haskell.org  Mon Mar 19 16:38:15 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 19 Mar 2018 16:38:15 +0000 (UTC)
Subject: [commit: ghc] master: Improve the warning message of qualified unused
 imports. (fad822e)
Message-ID: <20180319163815.B7C7D3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/fad822e2a5aa4373c3aa64e913e51fd5509c3f67/ghc

>---------------------------------------------------------------

commit fad822e2a5aa4373c3aa64e913e51fd5509c3f67
Author: HE, Tao <sighingnow at gmail.com>
Date:   Mon Mar 19 11:58:26 2018 -0400

    Improve the warning message of qualified unused imports.
    
    Pretty-print unused imported names unqualified unconditionally to
    make the warning message consistent for ambiguous/unambiguous
    identifiers.
    
    Signed-off-by: HE, Tao <sighingnow at gmail.com>
    
    Test Plan: make test TEST="T14881"
    
    Reviewers: bgamari, simonpj
    
    Reviewed By: simonpj
    
    Subscribers: simonpj, rwbarton, thomie, carter
    
    GHC Trac Issues: #14881
    
    Differential Revision: https://phabricator.haskell.org/D4461


>---------------------------------------------------------------

fad822e2a5aa4373c3aa64e913e51fd5509c3f67
 compiler/basicTypes/Name.hs                         |  6 +++++-
 compiler/rename/RnNames.hs                          |  7 +++++--
 testsuite/tests/rename/should_compile/T14881.hs     |  5 +++++
 testsuite/tests/rename/should_compile/T14881.stderr |  6 ++++++
 testsuite/tests/rename/should_compile/T14881Aux.hs  | 13 +++++++++++++
 testsuite/tests/rename/should_compile/all.T         |  1 +
 6 files changed, 35 insertions(+), 3 deletions(-)

diff --git a/compiler/basicTypes/Name.hs b/compiler/basicTypes/Name.hs
index 02eb067..6941dd9 100644
--- a/compiler/basicTypes/Name.hs
+++ b/compiler/basicTypes/Name.hs
@@ -70,7 +70,7 @@ module Name (
         NamedThing(..),
         getSrcLoc, getSrcSpan, getOccString, getOccFS,
 
-        pprInfixName, pprPrefixName, pprModulePrefix,
+        pprInfixName, pprPrefixName, pprModulePrefix, pprNameUnqualified,
         nameStableString,
 
         -- Re-export the OccName stuff
@@ -535,6 +535,10 @@ pprName (Name {n_sort = sort, n_uniq = uniq, n_occ = occ})
       System                  -> pprSystem sty uniq occ
       Internal                -> pprInternal sty uniq occ
 
+-- | Print the string of Name unqualifiedly directly.
+pprNameUnqualified :: Name -> SDoc
+pprNameUnqualified Name { n_occ = occ } = ppr_occ_name occ
+
 pprExternal :: PprStyle -> Unique -> Module -> OccName -> Bool -> BuiltInSyntax -> SDoc
 pprExternal sty uniq mod occ is_wired is_builtin
   | codeStyle sty = ppr mod <> char '_' <> ppr_z_occ_name occ
diff --git a/compiler/rename/RnNames.hs b/compiler/rename/RnNames.hs
index 769b34e..af00056 100644
--- a/compiler/rename/RnNames.hs
+++ b/compiler/rename/RnNames.hs
@@ -1401,9 +1401,12 @@ warnUnusedImport flag fld_env (L loc decl, used, unused)
     pp_mod      = ppr (unLoc (ideclName decl))
     pp_not_used = text "is redundant"
 
+    -- In warning message, pretty-print identifiers unqualified unconditionally
+    -- to improve the consistent for ambiguous/unambiguous identifiers.
+    -- See trac#14881.
     ppr_possible_field n = case lookupNameEnv fld_env n of
-                               Just (fld, p) -> ppr p <> parens (ppr fld)
-                               Nothing  -> ppr n
+                               Just (fld, p) -> pprNameUnqualified p <> parens (ppr fld)
+                               Nothing  -> pprNameUnqualified n
 
     -- Print unused names in a deterministic (lexicographic) order
     sort_unused = pprWithCommas ppr_possible_field $
diff --git a/testsuite/tests/rename/should_compile/T14881.hs b/testsuite/tests/rename/should_compile/T14881.hs
new file mode 100644
index 0000000..c1b955c
--- /dev/null
+++ b/testsuite/tests/rename/should_compile/T14881.hs
@@ -0,0 +1,5 @@
+module T14881 where
+
+import qualified T14881Aux as Aux (L(Cons), x, tail, adjust, length)
+
+x = Aux.Cons
diff --git a/testsuite/tests/rename/should_compile/T14881.stderr b/testsuite/tests/rename/should_compile/T14881.stderr
new file mode 100644
index 0000000..bfb6ca9
--- /dev/null
+++ b/testsuite/tests/rename/should_compile/T14881.stderr
@@ -0,0 +1,6 @@
+[1 of 2] Compiling T14881Aux        ( T14881Aux.hs, T14881Aux.o )
+[2 of 2] Compiling T14881           ( T14881.hs, T14881.o )
+
+T14881.hs:3:1: warning: [-Wunused-imports (in -Wextra)]
+    The qualified import of ‘adjust, length, L(tail), L(x)’
+    from module ‘T14881Aux’ is redundant
diff --git a/testsuite/tests/rename/should_compile/T14881Aux.hs b/testsuite/tests/rename/should_compile/T14881Aux.hs
new file mode 100644
index 0000000..13b8f31
--- /dev/null
+++ b/testsuite/tests/rename/should_compile/T14881Aux.hs
@@ -0,0 +1,13 @@
+module T14881Aux where
+
+-- unambiguous function name.
+adjust :: ()
+adjust = undefined
+
+-- ambiguous function name.
+length :: ()
+length = undefined
+
+data L = Cons { x :: Int      -- unambiguous field selector
+              , tail :: [Int] -- ambiguous field selector
+              }
diff --git a/testsuite/tests/rename/should_compile/all.T b/testsuite/tests/rename/should_compile/all.T
index 4eb584f..80bcb09 100644
--- a/testsuite/tests/rename/should_compile/all.T
+++ b/testsuite/tests/rename/should_compile/all.T
@@ -153,3 +153,4 @@ test('T12548', normal, compile, [''])
 test('T13132', normal, compile, [''])
 test('T13646', normal, compile, [''])
 test('LookupSub', [], multimod_compile, ['LookupSub', '-v0'])
+test('T14881', [], multimod_compile, ['T14881', '-W'])


From git at git.haskell.org  Mon Mar 19 16:38:29 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 19 Mar 2018 16:38:29 +0000 (UTC)
Subject: [commit: ghc] master: Get rid of more CPP in cmm/ and codeGen/
 (0db0e46)
Message-ID: <20180319163829.332EC3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/0db0e46c40a3a2af71f23033aa09a142d43b8538/ghc

>---------------------------------------------------------------

commit 0db0e46c40a3a2af71f23033aa09a142d43b8538
Author: Michal Terepeta <michal.terepeta at gmail.com>
Date:   Mon Mar 19 11:58:39 2018 -0400

    Get rid of more CPP in cmm/ and codeGen/
    
    This removes a bunch of unnecessary includes of `HsVersions.h` along
    with unnecessary CPP (e.g., due to checking for DEBUG which can be
    achieved by looking at `debugIsOn`)
    
    Signed-off-by: Michal Terepeta <michal.terepeta at gmail.com>
    
    Test Plan: ./validate
    
    Reviewers: bgamari, simonmar
    
    Reviewed By: bgamari
    
    Subscribers: rwbarton, thomie, carter
    
    Differential Revision: https://phabricator.haskell.org/D4462


>---------------------------------------------------------------

0db0e46c40a3a2af71f23033aa09a142d43b8538
 compiler/cmm/Cmm.hs               |  2 +-
 compiler/cmm/CmmExpr.hs           |  1 -
 compiler/cmm/MkGraph.hs           | 19 +++++++------------
 compiler/cmm/PprCmmDecl.hs        |  3 ---
 compiler/codeGen/CgUtils.hs       |  4 +---
 compiler/codeGen/StgCmmBind.hs    |  4 ----
 compiler/codeGen/StgCmmExpr.hs    |  7 ++++---
 compiler/codeGen/StgCmmForeign.hs |  4 ----
 compiler/codeGen/StgCmmHeap.hs    |  4 ----
 compiler/codeGen/StgCmmMonad.hs   | 13 +++++--------
 compiler/codeGen/StgCmmProf.hs    |  4 ----
 compiler/codeGen/StgCmmTicky.hs   |  4 +---
 12 files changed, 19 insertions(+), 50 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc 0db0e46c40a3a2af71f23033aa09a142d43b8538

From git at git.haskell.org  Mon Mar 19 16:38:43 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 19 Mar 2018 16:38:43 +0000 (UTC)
Subject: [commit: ghc] master: Hoopl: improve postorder calculation (bbcea13)
Message-ID: <20180319163843.D224D3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/bbcea13af845d41a9d51a932476eb841ba182ea5/ghc

>---------------------------------------------------------------

commit bbcea13af845d41a9d51a932476eb841ba182ea5
Author: Michal Terepeta <michal.terepeta at gmail.com>
Date:   Mon Mar 19 11:58:54 2018 -0400

    Hoopl: improve postorder calculation
    
    - Fix the naming and comments to indicate that we are calculating
      *reverse* postorder (and not the standard postorder).
    
    - Rewrite the calculation to avoid CPS code. I found it fairly
      difficult to understand and the new one seems faster (according to
      nofib, decreases compiler allocations by 0.2%)
    
    - Remove `LabelsPtr`, which seems unnecessary and could be *really*
      confusing. For instance, previously:
      `postorder_dfs_from <block with label X>`
      and
      `postorder_dfs_from <label X>`
      would actually mean quite different things (and give different
      results).
    
    - Change the `Dataflow` module to always use entry of the graph for
      reverse postorder calculation. This should be the only change in
      behavior of this commit.
    
      Previously, if the caller provided initial facts for some of the
      labels, we would use those labels for our postorder calculation.
      However, I don't think that's correct in general - if the initial
      facts did not contain the entry of the graph, we would never analyze
      the blocks reachable from the entry but unreachable from the labels
      provided with the initial facts. It seems that the only analysis that
      used this was proc-point analysis, which I think would always include
      the entry block (so I don't think there's any bug due to this).
    
    Signed-off-by: Michal Terepeta <michal.terepeta at gmail.com>
    
    Test Plan: ./validate
    
    Reviewers: bgamari, simonmar
    
    Reviewed By: simonmar
    
    Subscribers: rwbarton, thomie, carter
    
    Differential Revision: https://phabricator.haskell.org/D4464


>---------------------------------------------------------------

bbcea13af845d41a9d51a932476eb841ba182ea5
 compiler/cmm/CmmCommonBlockElim.hs                 |   4 +-
 compiler/cmm/CmmContFlowOpt.hs                     |   9 +-
 compiler/cmm/CmmLayoutStack.hs                     |   2 +-
 compiler/cmm/CmmProcPoint.hs                       |   6 +-
 compiler/cmm/CmmSink.hs                            |   2 +-
 compiler/cmm/CmmUtils.hs                           |   7 +-
 compiler/cmm/Hoopl/Dataflow.hs                     |  29 ++---
 compiler/cmm/Hoopl/Graph.hs                        | 118 +++++++++------------
 compiler/cmm/PprCmm.hs                             |   4 +-
 testsuite/tests/{ado => cmm}/Makefile              |   0
 testsuite/tests/cmm/should_run/HooplPostorder.hs   |  69 ++++++++++++
 .../tests/cmm/should_run/HooplPostorder.stdout     |   4 +
 .../should_compile => cmm/should_run}/Makefile     |   0
 testsuite/tests/cmm/should_run/all.T               |   4 +
 14 files changed, 156 insertions(+), 102 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc bbcea13af845d41a9d51a932476eb841ba182ea5

From git at git.haskell.org  Mon Mar 19 16:38:57 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 19 Mar 2018 16:38:57 +0000 (UTC)
Subject: [commit: ghc] master: Implement -dword-hex-literals (a00b88b)
Message-ID: <20180319163857.E5EF53A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/a00b88b9a27736c9c41f1921fcb6b7759ad8425e/ghc

>---------------------------------------------------------------

commit a00b88b9a27736c9c41f1921fcb6b7759ad8425e
Author: Andrew Martin <andrew.thaddeus at gmail.com>
Date:   Mon Mar 19 12:01:17 2018 -0400

    Implement -dword-hex-literals
    
    Provide flag for showing showing Word# and Word64# as hexadecimal when
    dumping GHC core.  The only affects Word, not Int, and it prefixes the
    hexadecimal with enough zeroes to make the total character count a power
    of two. For example:
    
    - 0x0C0C instead of 0xC0C
    - 0x00BA00BA instead of 0xBA00BA
    
    This also affects the presentation of Word# and Word64# in GHC's error
    messages. It is not expected that the flag will be used for this, but
    it is a side-effect worth noting.
    
    Test Plan: none
    
    Reviewers: bgamari, simonpj
    
    Reviewed By: simonpj
    
    Subscribers: simonpj, mpickering, rwbarton, thomie, carter, andrewthad
    
    GHC Trac Issues: #14872
    
    Differential Revision: https://phabricator.haskell.org/D4465


>---------------------------------------------------------------

a00b88b9a27736c9c41f1921fcb6b7759ad8425e
 compiler/main/DynFlags.hs      |  8 ++++++
 compiler/main/DynFlags.hs-boot | 20 +++++++-------
 compiler/utils/Outputable.hs   | 15 ++++++++---
 compiler/utils/Pretty.hs       | 61 +++++++++++++++++++++++++++++++++++++++++-
 docs/users_guide/debugging.rst | 14 ++++++++++
 5 files changed, 104 insertions(+), 14 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc a00b88b9a27736c9c41f1921fcb6b7759ad8425e

From git at git.haskell.org  Mon Mar 19 16:39:13 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 19 Mar 2018 16:39:13 +0000 (UTC)
Subject: [commit: ghc] master: PPC nativeGen: Add support for
 MO_SS_Conv_W32_W64 (b37a87b)
Message-ID: <20180319163913.A8BD43A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/b37a87b7ccc7c9b0a9da9aa987733c85050548b0/ghc

>---------------------------------------------------------------

commit b37a87b7ccc7c9b0a9da9aa987733c85050548b0
Author: Peter Trommler <ptrommler at acm.org>
Date:   Mon Mar 19 12:01:37 2018 -0400

    PPC nativeGen: Add support for MO_SS_Conv_W32_W64
    
    This is required by D4363. D4362 has the implementation for i386
    this commit adds PowerPC.
    
    Test Plan: validate
    
    Reviewers: erikd, hvr, simonmar, bgamari
    
    Reviewed By: bgamari
    
    Subscribers: rwbarton, thomie, carter
    
    Differential Revision: https://phabricator.haskell.org/D4468


>---------------------------------------------------------------

b37a87b7ccc7c9b0a9da9aa987733c85050548b0
 compiler/nativeGen/PPC/CodeGen.hs | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/compiler/nativeGen/PPC/CodeGen.hs b/compiler/nativeGen/PPC/CodeGen.hs
index e2c568c..7c345f2 100644
--- a/compiler/nativeGen/PPC/CodeGen.hs
+++ b/compiler/nativeGen/PPC/CodeGen.hs
@@ -382,6 +382,14 @@ iselExpr64 (CmmMachOp (MO_UU_Conv W32 W64) [expr]) = do
         mov_lo = MR rlo expr_reg
     return $ ChildCode64 (expr_code `snocOL` mov_lo `snocOL` mov_hi)
                          rlo
+
+iselExpr64 (CmmMachOp (MO_SS_Conv W32 W64) [expr]) = do
+    (expr_reg,expr_code) <- getSomeReg expr
+    (rlo, rhi) <- getNewRegPairNat II32
+    let mov_hi = SRA II32 rhi expr_reg (RIImm (ImmInt 31))
+        mov_lo = MR rlo expr_reg
+    return $ ChildCode64 (expr_code `snocOL` mov_lo `snocOL` mov_hi)
+                         rlo
 iselExpr64 expr
    = pprPanic "iselExpr64(powerpc)" (pprExpr expr)
 


From git at git.haskell.org  Mon Mar 19 16:39:27 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 19 Mar 2018 16:39:27 +0000 (UTC)
Subject: [commit: ghc] master: SPARC nativeGen: Support for MO_SS_Conv_W32_W64
 (5241f29)
Message-ID: <20180319163927.9B9993A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/5241f2987b3b0e791bfbe7b31529f5fbc600bdc7/ghc

>---------------------------------------------------------------

commit 5241f2987b3b0e791bfbe7b31529f5fbc600bdc7
Author: Peter Trommler <ptrommler at acm.org>
Date:   Mon Mar 19 12:02:03 2018 -0400

    SPARC nativeGen: Support for MO_SS_Conv_W32_W64
    
    Support for signed conversion from 32 bit to 64 bit
    integers is required by D4363.
    
    Test Plan: validate (perhaps also on SPARC)
    
    Reviewers: simonmar, bgamari, kgardas, jrtc27
    
    Reviewed By: bgamari
    
    Subscribers: rwbarton, thomie, carter
    
    Differential Revision: https://phabricator.haskell.org/D4489


>---------------------------------------------------------------

5241f2987b3b0e791bfbe7b31529f5fbc600bdc7
 compiler/nativeGen/SPARC/CodeGen/Gen64.hs | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/compiler/nativeGen/SPARC/CodeGen/Gen64.hs b/compiler/nativeGen/SPARC/CodeGen/Gen64.hs
index 8549fa0..6fa7482 100644
--- a/compiler/nativeGen/SPARC/CodeGen/Gen64.hs
+++ b/compiler/nativeGen/SPARC/CodeGen/Gen64.hs
@@ -193,6 +193,24 @@ iselExpr64 (CmmMachOp (MO_UU_Conv _ W64) [expr])
 
         return  $ ChildCode64 code r_dst_lo
 
+-- only W32 supported for now
+iselExpr64 (CmmMachOp (MO_SS_Conv W32 W64) [expr])
+ = do
+        r_dst_lo        <- getNewRegNat II32
+        let r_dst_hi    = getHiVRegFromLo r_dst_lo
+
+        -- compute expr and load it into r_dst_lo
+        (a_reg, a_code) <- getSomeReg expr
+
+        dflags          <- getDynFlags
+        let platform    = targetPlatform dflags
+            code        = a_code
+                `appOL` toOL
+                        [ SRA a_reg (RIImm (ImmInt 31)) r_dst_hi
+                        , mkRegRegMoveInstr platform a_reg r_dst_lo ]
+
+        return  $ ChildCode64 code r_dst_lo
+
 
 iselExpr64 expr
    = pprPanic "iselExpr64(sparc)" (ppr expr)


From git at git.haskell.org  Mon Mar 19 16:39:41 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 19 Mar 2018 16:39:41 +0000 (UTC)
Subject: [commit: ghc] master: [RFC] nativeGen: Add support for
 MO_SS_Conv_W32_W64 on i386 (d27336e)
Message-ID: <20180319163941.3A7643A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/d27336edcf2667c3c3908694247861beec3fc29b/ghc

>---------------------------------------------------------------

commit d27336edcf2667c3c3908694247861beec3fc29b
Author: Ben Gamari <bgamari.foss at gmail.com>
Date:   Mon Mar 19 12:02:29 2018 -0400

    [RFC] nativeGen: Add support for MO_SS_Conv_W32_W64 on i386
    
    This is required by D4288. However, this only handles i386; we will
    likely also need to do the same for PPC and SPARC, lest they break when
    D4288 is re-merged.
    
    Test Plan: Validate
    
    Reviewers: simonmar
    
    Reviewed By: simonmar
    
    Subscribers: rwbarton, thomie, carter
    
    Differential Revision: https://phabricator.haskell.org/D4362


>---------------------------------------------------------------

d27336edcf2667c3c3908694247861beec3fc29b
 compiler/nativeGen/X86/CodeGen.hs | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/compiler/nativeGen/X86/CodeGen.hs b/compiler/nativeGen/X86/CodeGen.hs
index 09757e7..a0b0673 100644
--- a/compiler/nativeGen/X86/CodeGen.hs
+++ b/compiler/nativeGen/X86/CodeGen.hs
@@ -468,6 +468,20 @@ iselExpr64 (CmmMachOp (MO_UU_Conv _ W64) [expr]) = do
                           r_dst_lo
             )
 
+iselExpr64 (CmmMachOp (MO_SS_Conv W32 W64) [expr]) = do
+     fn <- getAnyReg expr
+     r_dst_lo <-  getNewRegNat II32
+     let r_dst_hi = getHiVRegFromLo r_dst_lo
+         code = fn r_dst_lo
+     return (
+             ChildCode64 (code `snocOL`
+                          MOV II32 (OpReg r_dst_lo) (OpReg eax) `snocOL`
+                          CLTD II32 `snocOL`
+                          MOV II32 (OpReg eax) (OpReg r_dst_lo) `snocOL`
+                          MOV II32 (OpReg edx) (OpReg r_dst_hi))
+                          r_dst_lo
+            )
+
 iselExpr64 expr
    = pprPanic "iselExpr64(i386)" (ppr expr)
 


From git at git.haskell.org  Mon Mar 19 16:39:55 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 19 Mar 2018 16:39:55 +0000 (UTC)
Subject: [commit: ghc] master: Improve accuracy of get/setAllocationCounter
 (20cbb01)
Message-ID: <20180319163955.760923A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/20cbb0165e4d18df510e707791e761942d3c10f0/ghc

>---------------------------------------------------------------

commit 20cbb0165e4d18df510e707791e761942d3c10f0
Author: Ben Gamari <bgamari.foss at gmail.com>
Date:   Mon Mar 19 12:02:43 2018 -0400

    Improve accuracy of get/setAllocationCounter
    
    Summary:
    get/setAllocationCounter didn't take into account allocations in the
    current block. This was known at the time, but it turns out to be
    important to have more accuracy when using these in a fine-grained
    way.
    
    Test Plan:
    New unit test to test incrementally larger allocaitons.  Before I got
    results like this:
    
    ```
    +0
    +0
    +0
    +0
    +0
    +4096
    +0
    +0
    +0
    +0
    +0
    +4064
    +0
    +0
    +4088
    +4056
    +0
    +0
    +0
    +4088
    +4096
    +4056
    +4096
    ```
    
    Notice how the results aren't always monotonically increasing.  After
    this patch:
    
    ```
    +344
    +416
    +488
    +560
    +632
    +704
    +776
    +848
    +920
    +992
    +1064
    +1136
    +1208
    +1280
    +1352
    +1424
    +1496
    +1568
    +1640
    +1712
    +1784
    +1856
    +1928
    +2000
    +2072
    +2144
    ```
    
    Reviewers: hvr, erikd, simonmar, jrtc27, trommler
    
    Reviewed By: simonmar
    
    Subscribers: trommler, jrtc27, rwbarton, thomie, carter
    
    Differential Revision: https://phabricator.haskell.org/D4363


>---------------------------------------------------------------

20cbb0165e4d18df510e707791e761942d3c10f0
 compiler/codeGen/StgCmmForeign.hs                   |  4 ++--
 compiler/prelude/primops.txt.pp                     | 14 ++++++++++++++
 includes/Cmm.h                                      |  2 ++
 includes/rts/Threads.h                              |  2 --
 includes/stg/MiscClosures.h                         |  3 +++
 libraries/base/GHC/Conc/Sync.hs                     | 21 +++++----------------
 rts/PrimOps.cmm                                     | 20 ++++++++++++++++++++
 rts/RtsSymbols.c                                    |  4 ++--
 rts/Threads.c                                       | 13 +------------
 testsuite/tests/rts/all.T                           |  6 ++++++
 testsuite/tests/rts/alloccounter1.hs                | 19 +++++++++++++++++++
 .../tests/rts/alloccounter1.stdout                  |  0
 12 files changed, 74 insertions(+), 34 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc 20cbb0165e4d18df510e707791e761942d3c10f0

From git at git.haskell.org  Mon Mar 19 16:40:13 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 19 Mar 2018 16:40:13 +0000 (UTC)
Subject: [commit: ghc] master: CmmUtils: get rid of insertBlock (256577f)
Message-ID: <20180319164013.2CF313A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/256577fbde836f13c744418d38d18c17a369f7e9/ghc

>---------------------------------------------------------------

commit 256577fbde836f13c744418d38d18c17a369f7e9
Author: Michal Terepeta <michal.terepeta at gmail.com>
Date:   Mon Mar 19 12:03:20 2018 -0400

    CmmUtils: get rid of insertBlock
    
    `Hoopl.Graph` has almost exactly the same function, so let's use that.
    Also, use `IntMap.alter` to make it more efficient.
    
    Also switch `Hoopl` to use strict maps.
    
    Signed-off-by: Michal Terepeta <michal.terepeta at gmail.com>
    
    Test Plan: ./validate
    
    Reviewers: bgamari, simonmar
    
    Reviewed By: bgamari
    
    Subscribers: dfeuer, rwbarton, thomie, carter
    
    Differential Revision: https://phabricator.haskell.org/D4493


>---------------------------------------------------------------

256577fbde836f13c744418d38d18c17a369f7e9
 compiler/cmm/CmmProcPoint.hs      |  8 ++++----
 compiler/cmm/CmmUtils.hs          | 14 ++------------
 compiler/cmm/Hoopl/Collections.hs |  4 +++-
 compiler/cmm/Hoopl/Graph.hs       | 16 +++++++++-------
 compiler/cmm/Hoopl/Label.hs       |  1 +
 5 files changed, 19 insertions(+), 24 deletions(-)

diff --git a/compiler/cmm/CmmProcPoint.hs b/compiler/cmm/CmmProcPoint.hs
index e3eb1dc..bef8f38 100644
--- a/compiler/cmm/CmmProcPoint.hs
+++ b/compiler/cmm/CmmProcPoint.hs
@@ -242,11 +242,11 @@ splitAtProcPoints dflags entry_label callPPs procPoints procMap
                   (CmmProc (TopInfo {info_tbls = info_tbls})
                            top_l _ g@(CmmGraph {g_entry=entry})) =
   do -- Build a map from procpoints to the blocks they reach
-     let addBlock
+     let add_block
              :: LabelMap (LabelMap CmmBlock)
              -> CmmBlock
              -> LabelMap (LabelMap CmmBlock)
-         addBlock graphEnv b =
+         add_block graphEnv b =
            case mapLookup bid procMap of
              Just ProcPoint -> add graphEnv bid bid b
              Just (ReachedBy set) ->
@@ -265,7 +265,7 @@ splitAtProcPoints dflags entry_label callPPs procPoints procMap
                          regSetToList $
                          expectJust "ppLiveness" $ mapLookup pp liveness
 
-     graphEnv <- return $ foldlGraphBlocks addBlock mapEmpty g
+     graphEnv <- return $ foldlGraphBlocks add_block mapEmpty g
 
      -- Build a map from proc point BlockId to pairs of:
      --  * Labels for their new procedures
@@ -330,7 +330,7 @@ splitAtProcPoints dflags entry_label callPPs procPoints procMap
                   -- replace branches to procpoints with branches to jumps
                   blockEnv'' = toBlockMap $ replaceBranches jumpEnv $ ofBlockMap ppId blockEnv'
                   -- add the jump blocks to the graph
-                  blockEnv''' = foldl' (flip insertBlock) blockEnv'' jumpBlocks
+                  blockEnv''' = foldl' (flip addBlock) blockEnv'' jumpBlocks
               let g' = ofBlockMap ppId blockEnv'''
               -- pprTrace "g' pre jumps" (ppr g') $ do
               return (mapInsert ppId g' newGraphEnv)
diff --git a/compiler/cmm/CmmUtils.hs b/compiler/cmm/CmmUtils.hs
index aff16b3..53dbcdd 100644
--- a/compiler/cmm/CmmUtils.hs
+++ b/compiler/cmm/CmmUtils.hs
@@ -1,4 +1,4 @@
-{-# LANGUAGE CPP, GADTs, RankNTypes #-}
+{-# LANGUAGE GADTs, RankNTypes #-}
 
 -----------------------------------------------------------------------------
 --
@@ -56,7 +56,7 @@ module CmmUtils(
         -- * Operations that probably don't belong here
         modifyGraph,
 
-        ofBlockMap, toBlockMap, insertBlock,
+        ofBlockMap, toBlockMap,
         ofBlockList, toBlockList, bodyToBlockList,
         toBlockListEntryFirst, toBlockListEntryFirstFalseFallthrough,
         foldlGraphBlocks, mapGraphNodes, revPostorder, mapGraphNodes1,
@@ -65,8 +65,6 @@ module CmmUtils(
         blockTicks
   ) where
 
-#include "HsVersions.h"
-
 import GhcPrelude
 
 import TyCon    ( PrimRep(..), PrimElemRep(..) )
@@ -78,11 +76,9 @@ import BlockId
 import CLabel
 import Outputable
 import DynFlags
-import Util
 import CodeGen.Platform
 
 import Data.Word
-import Data.Maybe
 import Data.Bits
 import Hoopl.Graph
 import Hoopl.Label
@@ -495,12 +491,6 @@ toBlockMap (CmmGraph {g_graph=GMany NothingO body NothingO}) = body
 ofBlockMap :: BlockId -> LabelMap CmmBlock -> CmmGraph
 ofBlockMap entry bodyMap = CmmGraph {g_entry=entry, g_graph=GMany NothingO bodyMap NothingO}
 
-insertBlock :: CmmBlock -> LabelMap CmmBlock -> LabelMap CmmBlock
-insertBlock block map =
-  ASSERT(isNothing $ mapLookup id map)
-  mapInsert id block map
-  where id = entryLabel block
-
 toBlockList :: CmmGraph -> [CmmBlock]
 toBlockList g = mapElems $ toBlockMap g
 
diff --git a/compiler/cmm/Hoopl/Collections.hs b/compiler/cmm/Hoopl/Collections.hs
index b8072b3..ef7de4a 100644
--- a/compiler/cmm/Hoopl/Collections.hs
+++ b/compiler/cmm/Hoopl/Collections.hs
@@ -12,7 +12,7 @@ module Hoopl.Collections
 
 import GhcPrelude
 
-import qualified Data.IntMap as M
+import qualified Data.IntMap.Strict as M
 import qualified Data.IntSet as S
 
 import Data.List (foldl', foldl1')
@@ -66,6 +66,7 @@ class IsMap map where
   mapInsert :: KeyOf map -> a -> map a -> map a
   mapInsertWith :: (a -> a -> a) -> KeyOf map -> a -> map a -> map a
   mapDelete :: KeyOf map -> map a -> map a
+  mapAlter :: (Maybe a -> Maybe a) -> KeyOf map -> map a -> map a
 
   mapUnion :: map a -> map a -> map a
   mapUnionWithKey :: (KeyOf map -> a -> a -> a) -> map a -> map a -> map a
@@ -143,6 +144,7 @@ instance IsMap UniqueMap where
   mapInsert k v (UM m) = UM (M.insert k v m)
   mapInsertWith f k v (UM m) = UM (M.insertWith f k v m)
   mapDelete k (UM m) = UM (M.delete k m)
+  mapAlter f k (UM m) = UM (M.alter f k m)
 
   mapUnion (UM x) (UM y) = UM (M.union x y)
   mapUnionWithKey f (UM x) (UM y) = UM (M.unionWithKey f x y)
diff --git a/compiler/cmm/Hoopl/Graph.hs b/compiler/cmm/Hoopl/Graph.hs
index df1ebe3..0142f70 100644
--- a/compiler/cmm/Hoopl/Graph.hs
+++ b/compiler/cmm/Hoopl/Graph.hs
@@ -20,6 +20,7 @@ module Hoopl.Graph
 
 
 import GhcPrelude
+import Util
 
 import Hoopl.Label
 import Hoopl.Block
@@ -52,13 +53,14 @@ emptyBody = mapEmpty
 bodyList :: Body' block n -> [(Label,block n C C)]
 bodyList body = mapToList body
 
-addBlock :: NonLocal thing
-         => thing C C -> LabelMap (thing C C)
-         -> LabelMap (thing C C)
-addBlock b body
-  | mapMember lbl body = error $ "duplicate label " ++ show lbl ++ " in graph"
-  | otherwise          = mapInsert lbl b body
-  where lbl = entryLabel b
+addBlock
+    :: (NonLocal block, HasDebugCallStack)
+    => block C C -> LabelMap (block C C) -> LabelMap (block C C)
+addBlock block body = mapAlter add lbl body
+  where
+    lbl = entryLabel block
+    add Nothing = Just block
+    add _ = error $ "duplicate label " ++ show lbl ++ " in graph"
 
 
 -- ---------------------------------------------------------------------------
diff --git a/compiler/cmm/Hoopl/Label.hs b/compiler/cmm/Hoopl/Label.hs
index 8096fab..6eae115 100644
--- a/compiler/cmm/Hoopl/Label.hs
+++ b/compiler/cmm/Hoopl/Label.hs
@@ -87,6 +87,7 @@ instance IsMap LabelMap where
   mapInsert (Label k) v (LM m) = LM (mapInsert k v m)
   mapInsertWith f (Label k) v (LM m) = LM (mapInsertWith f k v m)
   mapDelete (Label k) (LM m) = LM (mapDelete k m)
+  mapAlter f (Label k) (LM m) = LM (mapAlter f k m)
 
   mapUnion (LM x) (LM y) = LM (mapUnion x y)
   mapUnionWithKey f (LM x) (LM y) = LM (mapUnionWithKey (f . mkHooplLabel) x y)


From git at git.haskell.org  Mon Mar 19 16:40:27 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 19 Mar 2018 16:40:27 +0000 (UTC)
Subject: [commit: ghc] master: Implement equalKeysUFM the right way (fbd9b88)
Message-ID: <20180319164027.19CE03A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/fbd9b886df92d1e0be0bdaacc7352273b504b78d/ghc

>---------------------------------------------------------------

commit fbd9b886df92d1e0be0bdaacc7352273b504b78d
Author: David Feuer <david.feuer at gmail.com>
Date:   Mon Mar 19 12:03:36 2018 -0400

    Implement equalKeysUFM the right way
    
    Originally, we compared the key lists, which was kind of silly.
    Then I changed it to something fancier ... and also silly.
    This is much more reasonable, should be faster, and is nice and
    clear.
    
    Reviewers: bgamari
    
    Reviewed By: bgamari
    
    Subscribers: rwbarton, thomie, carter
    
    Differential Revision: https://phabricator.haskell.org/D4500


>---------------------------------------------------------------

fbd9b886df92d1e0be0bdaacc7352273b504b78d
 compiler/utils/UniqFM.hs | 9 ++-------
 1 file changed, 2 insertions(+), 7 deletions(-)

diff --git a/compiler/utils/UniqFM.hs b/compiler/utils/UniqFM.hs
index 2a9b806..a80880f 100644
--- a/compiler/utils/UniqFM.hs
+++ b/compiler/utils/UniqFM.hs
@@ -78,12 +78,10 @@ import Outputable
 import Data.List (foldl')
 
 import qualified Data.IntMap as M
-import qualified Data.IntMap.Merge.Lazy as M
-import Control.Applicative (Const (..))
-import qualified Data.Monoid as Mon
 import qualified Data.IntSet as S
 import Data.Data
 import qualified Data.Semigroup as Semi
+import Data.Functor.Classes (Eq1 (..))
 
 
 newtype UniqFM ele = UFM (M.IntMap ele)
@@ -342,10 +340,7 @@ ufmToIntMap (UFM m) = m
 
 -- Determines whether two 'UniqFm's contain the same keys.
 equalKeysUFM :: UniqFM a -> UniqFM b -> Bool
-equalKeysUFM (UFM m1) (UFM m2) = Mon.getAll $ getConst $
-      M.mergeA (M.traverseMissing (\_ _ -> Const (Mon.All False)))
-               (M.traverseMissing (\_ _ -> Const (Mon.All False)))
-               (M.zipWithAMatched (\_ _ _ -> Const (Mon.All True))) m1 m2
+equalKeysUFM (UFM m1) (UFM m2) = liftEq (\_ _ -> True) m1 m2
 
 -- Instances
 


From git at git.haskell.org  Mon Mar 19 16:40:41 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 19 Mar 2018 16:40:41 +0000 (UTC)
Subject: [commit: ghc] master: Turn a TH Name for built-in syntax into an
 unqualified RdrName (9868f91)
Message-ID: <20180319164041.2C52E3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/9868f91fd9f04fdee241df69ae826feeae89a0b6/ghc

>---------------------------------------------------------------

commit 9868f91fd9f04fdee241df69ae826feeae89a0b6
Author: Chaitanya Koparkar <ckoparkar at gmail.com>
Date:   Mon Mar 19 12:04:03 2018 -0400

    Turn a TH Name for built-in syntax into an unqualified RdrName
    
    Previously, the Renamer would turn any fully qualified Template Haskell
    name into a corresponding fully qualified `RdrName`. But this is not
    what we want for built-in syntax, as it produces unnecessarily qualified
    names (eg. GHC.Types.[], GHC.Tuple.(,) etc.).
    
    Test Plan: ./validate
    
    Reviewers: RyanGlScott, bgamari, goldfire
    
    Reviewed By: RyanGlScott, bgamari
    
    Subscribers: rwbarton, thomie, carter
    
    GHC Trac Issues: #13776
    
    Differential Revision: https://phabricator.haskell.org/D4506


>---------------------------------------------------------------

9868f91fd9f04fdee241df69ae826feeae89a0b6
 compiler/hsSyn/Convert.hs                         |  8 +++++++-
 testsuite/tests/th/T13776.hs                      | 23 +++++++++++++++++++++++
 testsuite/tests/th/T13776.stderr                  | 14 ++++++++++++++
 testsuite/tests/th/T3319.stderr                   |  2 +-
 testsuite/tests/th/T5700.stderr                   |  2 +-
 testsuite/tests/th/TH_foreignInterruptible.stderr |  2 +-
 testsuite/tests/th/all.T                          |  1 +
 7 files changed, 48 insertions(+), 4 deletions(-)

diff --git a/compiler/hsSyn/Convert.hs b/compiler/hsSyn/Convert.hs
index 531f146..6440758 100644
--- a/compiler/hsSyn/Convert.hs
+++ b/compiler/hsSyn/Convert.hs
@@ -1625,8 +1625,14 @@ thRdrName loc ctxt_ns th_occ th_name
     occ :: OccName.OccName
     occ = mk_occ ctxt_ns th_occ
 
+-- Return an unqualified exact RdrName if we're dealing with built-in syntax.
+-- See Trac #13776.
 thOrigRdrName :: String -> TH.NameSpace -> PkgName -> ModName -> RdrName
-thOrigRdrName occ th_ns pkg mod = (mkOrig $! (mkModule (mk_pkg pkg) (mk_mod mod))) $! (mk_occ (mk_ghc_ns th_ns) occ)
+thOrigRdrName occ th_ns pkg mod =
+  let occ' = mk_occ (mk_ghc_ns th_ns) occ
+  in case isBuiltInOcc_maybe occ' of
+       Just name -> nameRdrName name
+       Nothing   -> (mkOrig $! (mkModule (mk_pkg pkg) (mk_mod mod))) $! occ'
 
 thRdrNameGuesses :: TH.Name -> [RdrName]
 thRdrNameGuesses (TH.Name occ flavour)
diff --git a/testsuite/tests/th/T13776.hs b/testsuite/tests/th/T13776.hs
new file mode 100644
index 0000000..6082825
--- /dev/null
+++ b/testsuite/tests/th/T13776.hs
@@ -0,0 +1,23 @@
+{-# LANGUAGE TemplateHaskell #-}
+
+module T13776 where
+
+import Language.Haskell.TH
+
+spliceTy1 :: $(conT ''(,) `appT` conT ''Int `appT` conT ''Int)
+spliceTy1 = (1,2)
+
+spliceTy2 :: $(conT ''[] `appT` conT ''Int)
+spliceTy2 = []
+
+spliceExp1 :: (Int, Int)
+spliceExp1 = $(conE '(,) `appE` litE (integerL 1) `appE` litE (integerL 1))
+
+spliceExp2 :: [Int]
+spliceExp2 = $(conE '[])
+
+splicePat1 :: (Int, Int) -> ()
+splicePat1 $(conP '(,) [litP (integerL 1), litP (integerL 1)]) = ()
+
+splicePat2 :: [Int] -> ()
+splicePat2 $(conP '[] []) = ()
diff --git a/testsuite/tests/th/T13776.stderr b/testsuite/tests/th/T13776.stderr
new file mode 100644
index 0000000..485dc64
--- /dev/null
+++ b/testsuite/tests/th/T13776.stderr
@@ -0,0 +1,14 @@
+T13776.hs:10:16-42: Splicing type
+    conT ''[] `appT` conT ''Int ======> [] Int
+T13776.hs:7:16-61: Splicing type
+    conT ''(,) `appT` conT ''Int `appT` conT ''Int ======> (,) Int Int
+T13776.hs:14:16-74: Splicing expression
+    conE '(,) `appE` litE (integerL 1) `appE` litE (integerL 1)
+  ======>
+    ((,) 1) 1
+T13776.hs:17:16-23: Splicing expression
+    conE '[] ======> []
+T13776.hs:20:14-61: Splicing pattern
+    conP '(,) [litP (integerL 1), litP (integerL 1)] ======> (,) 1 1
+T13776.hs:23:14-24: Splicing pattern
+    conP '[] [] ======> []
diff --git a/testsuite/tests/th/T3319.stderr b/testsuite/tests/th/T3319.stderr
index 44ec90f..b88b10f 100644
--- a/testsuite/tests/th/T3319.stderr
+++ b/testsuite/tests/th/T3319.stderr
@@ -4,4 +4,4 @@ T3319.hs:8:3-93: Splicing declarations
          (ImportF
             CCall Unsafe "&" (mkName "foo") (AppT (ConT ''Ptr) (ConT ''())))]
   ======>
-    foreign import ccall unsafe "&" foo :: Ptr GHC.Tuple.()
+    foreign import ccall unsafe "&" foo :: Ptr ()
diff --git a/testsuite/tests/th/T5700.stderr b/testsuite/tests/th/T5700.stderr
index 729a366..3564b8c 100644
--- a/testsuite/tests/th/T5700.stderr
+++ b/testsuite/tests/th/T5700.stderr
@@ -3,4 +3,4 @@ T5700.hs:8:3-9: Splicing declarations
   ======>
     instance C D where
       {-# INLINE inlinable #-}
-      inlinable _ = GHC.Tuple.()
+      inlinable _ = ()
diff --git a/testsuite/tests/th/TH_foreignInterruptible.stderr b/testsuite/tests/th/TH_foreignInterruptible.stderr
index 7131eee..4afc38a 100644
--- a/testsuite/tests/th/TH_foreignInterruptible.stderr
+++ b/testsuite/tests/th/TH_foreignInterruptible.stderr
@@ -8,4 +8,4 @@ TH_foreignInterruptible.hs:8:3-100: Splicing declarations
             (mkName "foo")
             (AppT (ConT ''Ptr) (ConT ''())))]
   ======>
-    foreign import ccall interruptible "&" foo :: Ptr GHC.Tuple.()
+    foreign import ccall interruptible "&" foo :: Ptr ()
diff --git a/testsuite/tests/th/all.T b/testsuite/tests/th/all.T
index e9f2838..b51059c 100644
--- a/testsuite/tests/th/all.T
+++ b/testsuite/tests/th/all.T
@@ -403,5 +403,6 @@ test('T14838', [], multimod_compile,
      ['T14838.hs', '-v0 -Wincomplete-patterns ' + config.ghc_th_way_flags])
 test('T14817', normal, compile, ['-v0 -ddump-splices -dsuppress-uniques'])
 test('T14843', normal, compile, ['-v0'])
+test('T13776', normal, compile, ['-ddump-splices -v0'])
 test('T14888', normal, compile,
     ['-v0 -ddump-splices -dsuppress-uniques ' + config.ghc_th_way_flags])


From git at git.haskell.org  Mon Mar 19 16:40:54 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 19 Mar 2018 16:40:54 +0000 (UTC)
Subject: [commit: ghc] master: Require GHC 8.2 to bootstrap GHC (e358854)
Message-ID: <20180319164054.8FB9B3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/e3588547686348876b2bf27e7389fd00e51521bb/ghc

>---------------------------------------------------------------

commit e3588547686348876b2bf27e7389fd00e51521bb
Author: Joachim Breitner <mail at joachim-breitner.de>
Date:   Mon Mar 19 12:05:22 2018 -0400

    Require GHC 8.2 to bootstrap GHC
    
    Reviewers: bgamari, hvr, RyanGlScott
    
    Reviewed By: RyanGlScott
    
    Subscribers: RyanGlScott, rwbarton, thomie, erikd, carter
    
    Differential Revision: https://phabricator.haskell.org/D4509


>---------------------------------------------------------------

e3588547686348876b2bf27e7389fd00e51521bb
 configure.ac | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/configure.ac b/configure.ac
index 1d3effb..e75fc6c 100644
--- a/configure.ac
+++ b/configure.ac
@@ -158,8 +158,8 @@ if test "$WithGhc" = ""
 then
     AC_MSG_ERROR([GHC is required.])
 fi
-FP_COMPARE_VERSIONS([$GhcVersion],[-lt],[8.0],
-    [AC_MSG_ERROR([GHC version 8.0 or later is required to compile GHC.])])
+FP_COMPARE_VERSIONS([$GhcVersion],[-lt],[8.2],
+    [AC_MSG_ERROR([GHC version 8.2 or later is required to compile GHC.])])
 
 if test `expr $GhcMinVersion % 2` = "1"
 then


From git at git.haskell.org  Mon Mar 19 16:41:13 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 19 Mar 2018 16:41:13 +0000 (UTC)
Subject: [commit: ghc] master: Fix #14934 by including axSub0R in
 typeNatCoAxiomRules (c3aea39)
Message-ID: <20180319164113.31E333A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/c3aea39678398fdf88166f30f0d01225a1874a32/ghc

>---------------------------------------------------------------

commit c3aea39678398fdf88166f30f0d01225a1874a32
Author: Ryan Scott <ryan.gl.scott at gmail.com>
Date:   Mon Mar 19 12:05:36 2018 -0400

    Fix #14934 by including axSub0R in typeNatCoAxiomRules
    
    For some reason, `axSub0R` was left out of `typeNatCoAxiomRules` in
    `TcTypeNats`, which led to disaster when trying to look up `Sub0R` from
    an interface file, as demonstrated in #14934.
    
    The fix is simple—just add `axSub0R` to that list. To help prevent
    an issue like this happening in the future, I added a
    `Note [Adding built-in type families]` to `TcTypeNats`, which
    contains a walkthrough of all the definitions in `TcTypeNats` you
    need to update when adding a new built-in type family.
    
    Test Plan: make test TEST=T14934
    
    Reviewers: bgamari, simonpj
    
    Reviewed By: simonpj
    
    Subscribers: simonpj, rwbarton, thomie, carter
    
    GHC Trac Issues: #14934
    
    Differential Revision: https://phabricator.haskell.org/D4508


>---------------------------------------------------------------

c3aea39678398fdf88166f30f0d01225a1874a32
 compiler/iface/TcIface.hs                          |  2 +-
 compiler/typecheck/TcTypeNats.hs                   | 93 +++++++++++++++++++---
 testsuite/tests/typecheck/should_compile/Makefile  |  5 ++
 testsuite/tests/typecheck/should_compile/T14934.hs |  9 +++
 .../should_compile/T14934a.hs}                     | 15 ++--
 testsuite/tests/typecheck/should_compile/all.T     |  2 +
 6 files changed, 110 insertions(+), 16 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc c3aea39678398fdf88166f30f0d01225a1874a32

From git at git.haskell.org  Mon Mar 19 16:41:27 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 19 Mar 2018 16:41:27 +0000 (UTC)
Subject: [commit: ghc] master: Don't permit data types with return kind
 Constraint (f748c52)
Message-ID: <20180319164127.621213A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/f748c52997f61a9f58eccbf4b8df0a0c8c6887e5/ghc

>---------------------------------------------------------------

commit f748c52997f61a9f58eccbf4b8df0a0c8c6887e5
Author: Ryan Scott <ryan.gl.scott at gmail.com>
Date:   Mon Mar 19 12:06:41 2018 -0400

    Don't permit data types with return kind Constraint
    
    Previously, GHC allowed all of the following:
    
    ```lang=haskell
    data Foo1 :: Constraint
    data family Foo2 :: Constraint
    data family Foo3 :: k
    data instance Foo3 :: Constraint
    ```
    
    Yikes! This is because GHC was confusing `Type` with `Constraint`
    due to careless use of the `isLiftedTypeKind` function. To respect
    this distinction, I swapped `isLiftedTypeKind` out for
    `tcIsStarKind`—which does respect this distinction—in the right
    places.
    
    Test Plan: make test TEST="T14048a T14048b T14048c"
    
    Reviewers: bgamari
    
    Reviewed By: bgamari
    
    Subscribers: goldfire, rwbarton, thomie, carter
    
    GHC Trac Issues: #14048
    
    Differential Revision: https://phabricator.haskell.org/D4479


>---------------------------------------------------------------

f748c52997f61a9f58eccbf4b8df0a0c8c6887e5
 compiler/typecheck/TcInstDcls.hs                     | 5 +++--
 compiler/typecheck/TcTyClsDecls.hs                   | 4 ++--
 testsuite/tests/typecheck/should_fail/T14048a.hs     | 6 ++++++
 testsuite/tests/typecheck/should_fail/T14048a.stderr | 5 +++++
 testsuite/tests/typecheck/should_fail/T14048b.hs     | 7 +++++++
 testsuite/tests/typecheck/should_fail/T14048b.stderr | 6 ++++++
 testsuite/tests/typecheck/should_fail/T14048c.hs     | 9 +++++++++
 testsuite/tests/typecheck/should_fail/T14048c.stderr | 5 +++++
 testsuite/tests/typecheck/should_fail/all.T          | 3 +++
 9 files changed, 46 insertions(+), 4 deletions(-)

diff --git a/compiler/typecheck/TcInstDcls.hs b/compiler/typecheck/TcInstDcls.hs
index 9f623fc..7e44c4a 100644
--- a/compiler/typecheck/TcInstDcls.hs
+++ b/compiler/typecheck/TcInstDcls.hs
@@ -41,6 +41,7 @@ import TcUnify
 import CoreSyn    ( Expr(..), mkApps, mkVarApps, mkLams )
 import MkCore     ( nO_METHOD_BINDING_ERROR_ID )
 import CoreUnfold ( mkInlineUnfoldingWithArity, mkDFunUnfolding )
+import Kind
 import Type
 import TcEvidence
 import TyCon
@@ -680,7 +681,7 @@ tcDataFamInstDecl mb_clsinfo
          -- Deal with any kind signature.
          -- See also Note [Arity of data families] in FamInstEnv
        ; (extra_tcbs, final_res_kind) <- tcDataKindSig full_tcbs res_kind'
-       ; checkTc (isLiftedTypeKind final_res_kind) (badKindSig True res_kind')
+       ; checkTc (tcIsStarKind final_res_kind) (badKindSig True res_kind')
 
        ; let extra_pats  = map (mkTyVarTy . binderVar) extra_tcbs
              all_pats    = pats' `chkAppend` extra_pats
@@ -722,7 +723,7 @@ tcDataFamInstDecl mb_clsinfo
        ; checkValidFamPats mb_clsinfo fam_tc tvs' [] pats' extra_pats pp_hs_pats
 
          -- Result kind must be '*' (otherwise, we have too few patterns)
-       ; checkTc (isLiftedTypeKind final_res_kind) $
+       ; checkTc (tcIsStarKind final_res_kind) $
          tooFewParmsErr (tyConArity fam_tc)
 
        ; checkValidTyCon rep_tc
diff --git a/compiler/typecheck/TcTyClsDecls.hs b/compiler/typecheck/TcTyClsDecls.hs
index 7436b0d..39697d6 100644
--- a/compiler/typecheck/TcTyClsDecls.hs
+++ b/compiler/typecheck/TcTyClsDecls.hs
@@ -886,7 +886,7 @@ tcFamDecl1 parent (FamilyDecl { fdInfo = fam_info, fdLName = tc_lname@(L _ tc_na
   -- Data families might have a variable return kind.
   -- See See Note [Arity of data families] in FamInstEnv.
   ; (extra_binders, final_res_kind) <- tcDataKindSig binders res_kind
-  ; checkTc (isLiftedTypeKind final_res_kind
+  ; checkTc (tcIsStarKind final_res_kind
              || isJust (tcGetCastedTyVar_maybe final_res_kind))
             (badKindSig False res_kind)
 
@@ -1038,7 +1038,7 @@ tcDataDefn roles_info
        ; let hsc_src = tcg_src tcg_env
        ; (extra_bndrs, final_res_kind) <- tcDataKindSig tycon_binders res_kind
        ; unless (mk_permissive_kind hsc_src cons) $
-         checkTc (isLiftedTypeKind final_res_kind) (badKindSig True res_kind)
+         checkTc (tcIsStarKind final_res_kind) (badKindSig True res_kind)
 
        ; let final_bndrs  = tycon_binders `chkAppend` extra_bndrs
              roles        = roles_info tc_name
diff --git a/testsuite/tests/typecheck/should_fail/T14048a.hs b/testsuite/tests/typecheck/should_fail/T14048a.hs
new file mode 100644
index 0000000..c717127
--- /dev/null
+++ b/testsuite/tests/typecheck/should_fail/T14048a.hs
@@ -0,0 +1,6 @@
+{-# LANGUAGE ConstraintKinds #-}
+module T14048a where
+
+import Data.Kind
+
+data Foo :: Constraint
diff --git a/testsuite/tests/typecheck/should_fail/T14048a.stderr b/testsuite/tests/typecheck/should_fail/T14048a.stderr
new file mode 100644
index 0000000..48a91c7
--- /dev/null
+++ b/testsuite/tests/typecheck/should_fail/T14048a.stderr
@@ -0,0 +1,5 @@
+
+T14048a.hs:6:1: error:
+    • Kind signature on data type declaration has non-* return kind
+        Constraint
+    • In the data declaration for ‘Foo’
diff --git a/testsuite/tests/typecheck/should_fail/T14048b.hs b/testsuite/tests/typecheck/should_fail/T14048b.hs
new file mode 100644
index 0000000..d2f6f74
--- /dev/null
+++ b/testsuite/tests/typecheck/should_fail/T14048b.hs
@@ -0,0 +1,7 @@
+{-# LANGUAGE ConstraintKinds #-}
+{-# LANGUAGE TypeFamilies #-}
+module T14048b where
+
+import Data.Kind
+
+data family Foo :: Constraint
diff --git a/testsuite/tests/typecheck/should_fail/T14048b.stderr b/testsuite/tests/typecheck/should_fail/T14048b.stderr
new file mode 100644
index 0000000..fe78d9f
--- /dev/null
+++ b/testsuite/tests/typecheck/should_fail/T14048b.stderr
@@ -0,0 +1,6 @@
+
+T14048b.hs:7:1: error:
+    • Kind signature on data type declaration has non-*
+      and non-variable return kind
+        Constraint
+    • In the data family declaration for ‘Foo’
diff --git a/testsuite/tests/typecheck/should_fail/T14048c.hs b/testsuite/tests/typecheck/should_fail/T14048c.hs
new file mode 100644
index 0000000..e81e454
--- /dev/null
+++ b/testsuite/tests/typecheck/should_fail/T14048c.hs
@@ -0,0 +1,9 @@
+{-# LANGUAGE ConstraintKinds #-}
+{-# LANGUAGE PolyKinds #-}
+{-# LANGUAGE TypeFamilies #-}
+module T14048c where
+
+import Data.Kind
+
+data family   Foo :: k
+data instance Foo :: Constraint
diff --git a/testsuite/tests/typecheck/should_fail/T14048c.stderr b/testsuite/tests/typecheck/should_fail/T14048c.stderr
new file mode 100644
index 0000000..7e83d19
--- /dev/null
+++ b/testsuite/tests/typecheck/should_fail/T14048c.stderr
@@ -0,0 +1,5 @@
+
+T14048c.hs:9:1: error:
+    • Kind signature on data type declaration has non-* return kind
+        Constraint
+    • In the data instance declaration for ‘Foo’
diff --git a/testsuite/tests/typecheck/should_fail/all.T b/testsuite/tests/typecheck/should_fail/all.T
index 5377fef..f01cbe1 100644
--- a/testsuite/tests/typecheck/should_fail/all.T
+++ b/testsuite/tests/typecheck/should_fail/all.T
@@ -457,6 +457,9 @@ test('T14000', normal, compile_fail, [''])
 test('T14055', normal, compile_fail, [''])
 test('T13909', normal, compile_fail, [''])
 test('T13929', normal, compile_fail, [''])
+test('T14048a', normal, compile_fail, [''])
+test('T14048b', normal, compile_fail, [''])
+test('T14048c', normal, compile_fail, [''])
 test('T14232', normal, compile_fail, [''])
 test('T14325', normal, compile_fail, [''])
 test('T14350', normal, compile_fail, [''])


From git at git.haskell.org  Mon Mar 19 16:41:41 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 19 Mar 2018 16:41:41 +0000 (UTC)
Subject: [commit: ghc] master: Update tests for #12870 to pass with a slow run
 of the testsuite. (fdec06a)
Message-ID: <20180319164141.03AB03A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/fdec06a201f81467badb9e2a5d43b4a85564dff9/ghc

>---------------------------------------------------------------

commit fdec06a201f81467badb9e2a5d43b4a85564dff9
Author: Andreas Klebinger <klebinger.andreas at gmx.at>
Date:   Mon Mar 19 12:06:54 2018 -0400

    Update tests for #12870 to pass with a slow run of the testsuite.
    
    Test Plan: make slow
    
    Reviewers: bgamari, erikd, simonmar
    
    Reviewed By: bgamari
    
    Subscribers: rwbarton, thomie, carter
    
    GHC Trac Issues: #12870
    
    Differential Revision: https://phabricator.haskell.org/D4486


>---------------------------------------------------------------

fdec06a201f81467badb9e2a5d43b4a85564dff9
 testsuite/tests/rts/flags/Makefile   |  3 ---
 testsuite/tests/rts/flags/T12870.hs  |  3 ++-
 testsuite/tests/rts/flags/T12870g.hs |  3 ++-
 testsuite/tests/rts/flags/all.T      | 39 +++++++++++++++++++++---------------
 4 files changed, 27 insertions(+), 21 deletions(-)

diff --git a/testsuite/tests/rts/flags/Makefile b/testsuite/tests/rts/flags/Makefile
index 6190047..9101fbd 100644
--- a/testsuite/tests/rts/flags/Makefile
+++ b/testsuite/tests/rts/flags/Makefile
@@ -1,6 +1,3 @@
 TOP=../../..
 include $(TOP)/mk/boilerplate.mk
 include $(TOP)/mk/test.mk
-
-T1791:
-	'$(TEST_HC)' T1791.hs -o T1791 -O -rtsopts
diff --git a/testsuite/tests/rts/flags/T12870.hs b/testsuite/tests/rts/flags/T12870.hs
index 8d536d5..69086cd 100644
--- a/testsuite/tests/rts/flags/T12870.hs
+++ b/testsuite/tests/rts/flags/T12870.hs
@@ -1,4 +1,5 @@
-module T12870 where
+--We check if RTS arguments are properly filtered/passed along
+--by outputting them to stdout.
 
 import System.Environment
 
diff --git a/testsuite/tests/rts/flags/T12870g.hs b/testsuite/tests/rts/flags/T12870g.hs
index e409349..3efd633 100644
--- a/testsuite/tests/rts/flags/T12870g.hs
+++ b/testsuite/tests/rts/flags/T12870g.hs
@@ -1,4 +1,5 @@
-module T12870g where
+--We check the generation count as a way to verify an RTS argument
+--was actually parsed and accepted by the RTS.
 
 import GHC.RTS.Flags (getGCFlags, generations)
 
diff --git a/testsuite/tests/rts/flags/all.T b/testsuite/tests/rts/flags/all.T
index 33a28e5..548fcd8 100644
--- a/testsuite/tests/rts/flags/all.T
+++ b/testsuite/tests/rts/flags/all.T
@@ -1,44 +1,51 @@
 #Standard handling of RTS arguments
 test('T12870a',
-    [extra_run_opts('+RTS -G2 -RTS arg1 --RTS +RTS arg2'), extra_files(['T12870.hs'])],
+    [extra_run_opts('+RTS -G2 -RTS arg1 --RTS +RTS arg2'), extra_files(['T12870.hs']),
+        omit_ways(['ghci'])],
     multimod_compile_and_run,
-    ['T12870', '-rtsopts -main-is T12870'])
+    ['T12870', '-rtsopts'])
 
 test('T12870b',
     [extra_run_opts('+RTS -G2 -RTS arg1 --RTS +RTS arg2'), extra_files(['T12870.hs']),
-        exit_code(1), ignore_stderr],
+        exit_code(1), ignore_stderr, omit_ways(['ghci'])],
     multimod_compile_and_run,
-    ['T12870', '-rtsopts=none -main-is T12870'])
+    ['T12870', '-rtsopts=none'])
 
 test('T12870c',
     [extra_run_opts('+RTS -G2 -RTS arg1 --RTS +RTS arg2'), extra_files(['T12870.hs']),
-    exit_code(1)],
+        exit_code(1), omit_ways(['ghci'])],
     multimod_compile_and_run,
-    ['T12870', '-rtsopts=some -main-is T12870'])
+    ['T12870', '-rtsopts=some'])
 
 test('T12870d',
-    [extra_run_opts('+RTS -G2 -RTS arg1 --RTS +RTS arg2'), extra_files(['T12870.hs'])],
+    [extra_run_opts('+RTS -G2 -RTS arg1 --RTS +RTS arg2'), extra_files(['T12870.hs']),
+        omit_ways(['ghci'])],
     multimod_compile_and_run,
-    ['T12870', '-main-is T12870'])
+    ['T12870', ''])
 
 #RTS options should be passed along to the program
 test('T12870e',
-    [extra_run_opts('+RTS -G2 -RTS arg1 --RTS +RTS arg2'), extra_files(['T12870.hs'])],
+    [extra_run_opts('+RTS -G2 -RTS arg1 --RTS +RTS arg2'), extra_files(['T12870.hs']),
+        omit_ways(['ghci', 'threaded2'])],
     multimod_compile_and_run,
-    ['T12870', '-rtsopts=ignore -main-is T12870'])
+    ['T12870', '-rtsopts=ignore'])
+
 test('T12870f',
-    [extra_run_opts('+RTS -G2 -RTS arg1 --RTS +RTS arg2'), extra_files(['T12870.hs'])],
+    [extra_run_opts('+RTS -G2 -RTS arg1 --RTS +RTS arg2'), extra_files(['T12870.hs']),
+        omit_ways(['ghci', 'threaded2'])],
     multimod_compile_and_run,
-    ['T12870', '-rtsopts=ignoreAll -main-is T12870'])
+    ['T12870', '-rtsopts=ignoreAll'])
 
 #Check handling of env variables
 test('T12870g',
-    [extra_files(['T12870g.hs']), cmd_prefix('GHCRTS=-G7 '), extra_files(['T12870g.hs'])],
+    [extra_files(['T12870g.hs']), cmd_prefix('GHCRTS=-G7 '), extra_files(['T12870g.hs']),
+        omit_ways(['ghci'])],
     multimod_compile_and_run,
-    ['T12870g', '-rtsopts -main-is T12870g -with-rtsopts="-G3"'])
+    ['T12870g', '-rtsopts -with-rtsopts="-G3"'])
 
 test('T12870h',
-    [extra_files(['T12870g.hs']), cmd_prefix('GHCRTS=-G7 '), extra_files(['T12870g.hs'])],
+    [extra_files(['T12870g.hs']), cmd_prefix('GHCRTS=-G7 '), extra_files(['T12870g.hs']),
+        omit_ways(['ghci'])],
     multimod_compile_and_run,
-    ['T12870g', '-rtsopts=ignoreAll -main-is T12870g -with-rtsopts="-G3"'])
+    ['T12870g', '-rtsopts=ignoreAll -with-rtsopts="-G3"'])
 


From git at git.haskell.org  Mon Mar 19 16:46:39 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 19 Mar 2018 16:46:39 +0000 (UTC)
Subject: [commit: packages/array] master: Remove compatibility with GHC <8
 (1d0435f)
Message-ID: <20180319164639.28FB23A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/array

On branch  : master
Link       : http://git.haskell.org/packages/array.git/commitdiff/1d0435f4937f03901e32304e279f46ce19b0f089

>---------------------------------------------------------------

commit 1d0435f4937f03901e32304e279f46ce19b0f089
Author: David Feuer <David.Feuer at gmail.com>
Date:   Mon Mar 19 12:46:14 2018 -0400

    Remove compatibility with GHC <8
    
    Summary: These have shifted out of the support window.
    
    Reviewers: bgamari, hvr, RyanGlScott
    
    Reviewed By: RyanGlScott
    
    Subscribers: RyanGlScott
    
    Differential Revision: https://phabricator.haskell.org/D4499


>---------------------------------------------------------------

1d0435f4937f03901e32304e279f46ce19b0f089
 Data/Array.hs              |  2 --
 Data/Array/Base.hs         | 45 ++++++++++++---------------------------------
 Data/Array/IO/Internals.hs | 29 +++++------------------------
 Data/Array/ST.hs           |  9 ---------
 array.cabal                |  5 ++---
 changelog.md               |  5 +++++
 6 files changed, 24 insertions(+), 71 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc 1d0435f4937f03901e32304e279f46ce19b0f089

From git at git.haskell.org  Mon Mar 19 17:25:42 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 19 Mar 2018 17:25:42 +0000 (UTC)
Subject: [commit: ghc] master: Bump array submodule (98c1f22)
Message-ID: <20180319172542.34F563A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/98c1f222c160fd4f07e4ab68d0504ab5ce364b61/ghc

>---------------------------------------------------------------

commit 98c1f222c160fd4f07e4ab68d0504ab5ce364b61
Author: Ben Gamari <ben at smart-cactus.org>
Date:   Mon Mar 19 12:46:44 2018 -0400

    Bump array submodule


>---------------------------------------------------------------

98c1f222c160fd4f07e4ab68d0504ab5ce364b61
 libraries/array | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libraries/array b/libraries/array
index 9d63218..1d0435f 160000
--- a/libraries/array
+++ b/libraries/array
@@ -1 +1 @@
-Subproject commit 9d63218fd067ff4885c0efa43b388238421a5c89
+Subproject commit 1d0435f4937f03901e32304e279f46ce19b0f089


From git at git.haskell.org  Mon Mar 19 17:25:56 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 19 Mar 2018 17:25:56 +0000 (UTC)
Subject: [commit: ghc] master: Fix typo in user guide about ConstraintKinds
 (960cd42)
Message-ID: <20180319172556.6FD6E3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/960cd424fb2ca99389c8f041d519d661494d07c1/ghc

>---------------------------------------------------------------

commit 960cd424fb2ca99389c8f041d519d661494d07c1
Author: Frank Steffahn <fdsteffahn at gmail.com>
Date:   Tue Mar 13 23:29:04 2018 +0100

    Fix typo in user guide about ConstraintKinds
    
    The backslash currently in this type signature makes no sense. Without it, the example is fine.


>---------------------------------------------------------------

960cd424fb2ca99389c8f041d519d661494d07c1
 docs/users_guide/glasgow_exts.rst | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/docs/users_guide/glasgow_exts.rst b/docs/users_guide/glasgow_exts.rst
index c6cff92..49c6ed4 100644
--- a/docs/users_guide/glasgow_exts.rst
+++ b/docs/users_guide/glasgow_exts.rst
@@ -9442,7 +9442,7 @@ The following things have kind ``Constraint``:
 -  Anything whose form is not yet known, but the user has declared to
    have kind ``Constraint`` (for which they need to import it from
    ``GHC.Exts``). So for example
-   ``type Foo (f :: \* -> Constraint) = forall b. f b => b -> b``
+   ``type Foo (f :: * -> Constraint) = forall b. f b => b -> b``
    is allowed, as well as examples involving type families: ::
 
        type family Typ a b :: Constraint


From git at git.haskell.org  Mon Mar 19 17:26:11 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 19 Mar 2018 17:26:11 +0000 (UTC)
Subject: [commit: ghc] master: Fix typo (82e8d1f)
Message-ID: <20180319172611.C67213A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/82e8d1fb82b2d2334516571bb1bc32ee9025df90/ghc

>---------------------------------------------------------------

commit 82e8d1fb82b2d2334516571bb1bc32ee9025df90
Author: Gabor Greif <ggreif at gmail.com>
Date:   Thu Mar 8 12:13:08 2018 +0100

    Fix typo


>---------------------------------------------------------------

82e8d1fb82b2d2334516571bb1bc32ee9025df90
 rts/posix/itimer/Pthread.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/rts/posix/itimer/Pthread.c b/rts/posix/itimer/Pthread.c
index e15ac25..c45d57e 100644
--- a/rts/posix/itimer/Pthread.c
+++ b/rts/posix/itimer/Pthread.c
@@ -10,7 +10,7 @@
  * We use a realtime timer by default.  I found this much more
  * reliable than a CPU timer:
  *
- * Experiments with different frequences: using
+ * Experiments with different frequencies: using
  * CLOCK_REALTIME/CLOCK_MONOTONIC on Linux 2.6.32,
  *     1000us has  <1% impact on runtime
  *      100us has  ~2% impact on runtime


From git at git.haskell.org  Mon Mar 19 17:26:25 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 19 Mar 2018 17:26:25 +0000 (UTC)
Subject: [commit: ghc] master: gen-data-layout.sh: Use bash array for
 readability (b3b394b)
Message-ID: <20180319172625.4E6BC3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/b3b394b44e42f19ab7c23668a4008e4f728b51ba/ghc

>---------------------------------------------------------------

commit b3b394b44e42f19ab7c23668a4008e4f728b51ba
Author: John Ericson <John.Ericson at Obsidian.Systems>
Date:   Mon Mar 19 13:24:46 2018 -0400

    gen-data-layout.sh: Use bash array for readability
    
    Reviewers: angerman, bgamari
    
    Reviewed By: bgamari
    
    Subscribers: rwbarton, thomie, carter
    
    Differential Revision: https://phabricator.haskell.org/D4511


>---------------------------------------------------------------

b3b394b44e42f19ab7c23668a4008e4f728b51ba
 utils/llvm-targets/gen-data-layout.sh | 33 ++++++++++++++++++++++-----------
 1 file changed, 22 insertions(+), 11 deletions(-)

diff --git a/utils/llvm-targets/gen-data-layout.sh b/utils/llvm-targets/gen-data-layout.sh
index 834a978..4f0b240 100755
--- a/utils/llvm-targets/gen-data-layout.sh
+++ b/utils/llvm-targets/gen-data-layout.sh
@@ -16,17 +16,28 @@
 # Add missing targets to the list below to have them included in
 # llvm-targets file.
 
-# Target sets
-WINDOWS_x86="i386-unknown-windows i686-unknown-windows x86_64-unknown-windows"
-LINUX_ARM="arm-unknown-linux-gnueabihf armv6-unknown-linux-gnueabihf armv7-unknown-linux-gnueabihf aarch64-unknown-linux-gnu aarch64-unknown-linux armv7a-unknown-linux-gnueabi"
-LINUX_x86="i386-unknown-linux-gnu i386-unknown-linux x86_64-unknown-linux-gnu x86_64-unknown-linux"
-ANDROID="armv7-unknown-linux-androideabi aarch64-unknown-linux-android"
-QNX="arm-unknown-nto-qnx-eabi"
-MACOS="i386-apple-darwin x86_64-apple-darwin"
-IOS="armv7-apple-ios arm64-apple-ios i386-apple-ios x86_64-apple-ios"
+# Target sets for which to generate the llvm-targets file
+TARGETS=(
+    # Windows x86
+    "i386-unknown-windows" "i686-unknown-windows" "x86_64-unknown-windows"
 
-# targets for which to generate the llvm-targets file
-TARGETS="${WINDOWS_x86} ${LINUX_ARM} ${LINUX_x86} ${ANDROID} ${QNX} ${MACOS} ${IOS}"
+    # Linux ARM
+    "arm-unknown-linux-gnueabihf" "armv6-unknown-linux-gnueabihf"
+    "armv7-unknown-linux-gnueabihf" "armv7a-unknown-linux-gnueabi"
+    "aarch64-unknown-linux-gnu" "aarch64-unknown-linux"
+    # Linux x86
+    "i386-unknown-linux-gnu" "i386-unknown-linux" "x86_64-unknown-linux-gnu" "x86_64-unknown-linux"
+    # Linux Android
+    "armv7-unknown-linux-androideabi" "aarch64-unknown-linux-android"
+
+    # QNX
+    "arm-unknown-nto-qnx-eabi"
+
+    # macOS
+    "i386-apple-darwin" "x86_64-apple-darwin"
+    # iOS
+    "armv7-apple-ios arm64-apple-ios" "i386-apple-ios x86_64-apple-ios"
+)
 
 # given the call to clang -c11 that clang --target -v generates,
 # parse the -target-cpu <CPU> and -target-feature <feature> from
@@ -61,7 +72,7 @@ FST=1
 FILE=_____dummy.c
 touch $FILE
 
-for target in $TARGETS; do
+for target in "${TARGETS[@]}"; do
     # find the cpu and attributes emitte by clang for the given $target
     CPU=""
     ATTR=()


From git at git.haskell.org  Mon Mar 19 19:21:54 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 19 Mar 2018 19:21:54 +0000 (UTC)
Subject: [commit: ghc] wip/T14068: Require GHC 8.2 to bootstrap GHC (4ba3bd7)
Message-ID: <20180319192154.75F9F3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/T14068
Link       : http://ghc.haskell.org/trac/ghc/changeset/4ba3bd75ce0470c243b303bea0d581cc8e307f53/ghc

>---------------------------------------------------------------

commit 4ba3bd75ce0470c243b303bea0d581cc8e307f53
Author: Joachim Breitner <mail at joachim-breitner.de>
Date:   Sun Mar 18 20:36:06 2018 -0400

    Require GHC 8.2 to bootstrap GHC
    
    Summary: It started to fail on me using 8.0
    
    Reviewers: bgamari, hvr
    
    Subscribers: rwbarton, thomie, erikd, carter
    
    Differential Revision: https://phabricator.haskell.org/D4509


>---------------------------------------------------------------

4ba3bd75ce0470c243b303bea0d581cc8e307f53
 configure.ac | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/configure.ac b/configure.ac
index 1d3effb..e75fc6c 100644
--- a/configure.ac
+++ b/configure.ac
@@ -158,8 +158,8 @@ if test "$WithGhc" = ""
 then
     AC_MSG_ERROR([GHC is required.])
 fi
-FP_COMPARE_VERSIONS([$GhcVersion],[-lt],[8.0],
-    [AC_MSG_ERROR([GHC version 8.0 or later is required to compile GHC.])])
+FP_COMPARE_VERSIONS([$GhcVersion],[-lt],[8.2],
+    [AC_MSG_ERROR([GHC version 8.2 or later is required to compile GHC.])])
 
 if test `expr $GhcMinVersion % 2` = "1"
 then


From git at git.haskell.org  Mon Mar 19 19:21:57 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 19 Mar 2018 19:21:57 +0000 (UTC)
Subject: [commit: ghc] wip/T14068: Merge branch 'master' into wip/T14068
 (9c6785b)
Message-ID: <20180319192157.C88763A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/T14068
Link       : http://ghc.haskell.org/trac/ghc/changeset/9c6785b5e9d4071ff9deee92afb4fa01555e7358/ghc

>---------------------------------------------------------------

commit 9c6785b5e9d4071ff9deee92afb4fa01555e7358
Merge: 20b00bd 4ba3bd7
Author: Joachim Breitner <mail at joachim-breitner.de>
Date:   Mon Mar 19 09:53:00 2018 -0400

    Merge branch 'master' into wip/T14068



>---------------------------------------------------------------


Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc 9c6785b5e9d4071ff9deee92afb4fa01555e7358

From git at git.haskell.org  Mon Mar 19 19:22:00 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 19 Mar 2018 19:22:00 +0000 (UTC)
Subject: [commit: ghc] wip/T14068: Prefix the loopification name with $l
 (9245c4b)
Message-ID: <20180319192200.95DBF3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/T14068
Link       : http://ghc.haskell.org/trac/ghc/changeset/9245c4bbc2156b3b84f253c97cc2ee8bd8b7dd98/ghc

>---------------------------------------------------------------

commit 9245c4bbc2156b3b84f253c97cc2ee8bd8b7dd98
Author: Joachim Breitner <mail at joachim-breitner.de>
Date:   Mon Mar 19 15:19:16 2018 -0400

    Prefix the loopification name with $l


>---------------------------------------------------------------

9245c4bbc2156b3b84f253c97cc2ee8bd8b7dd98
 compiler/basicTypes/Id.hs      | 6 +++++-
 compiler/basicTypes/OccName.hs | 5 +++--
 compiler/coreSyn/CoreOpt.hs    | 2 +-
 3 files changed, 9 insertions(+), 4 deletions(-)

diff --git a/compiler/basicTypes/Id.hs b/compiler/basicTypes/Id.hs
index fbece0e..629f85f 100644
--- a/compiler/basicTypes/Id.hs
+++ b/compiler/basicTypes/Id.hs
@@ -40,7 +40,7 @@ module Id (
         mkSysLocal, mkSysLocalM, mkSysLocalOrCoVar, mkSysLocalOrCoVarM,
         mkUserLocal, mkUserLocalOrCoVar,
         mkTemplateLocals, mkTemplateLocalsNum, mkTemplateLocal,
-        mkWorkerId,
+        mkWorkerId, mkLoopId,
 
         -- ** Taking an Id apart
         idName, idType, idUnique, idInfo, idDetails,
@@ -347,6 +347,10 @@ mkWorkerId :: Unique -> Id -> Type -> Id
 mkWorkerId uniq unwrkr ty
   = mkLocalIdOrCoVar (mkDerivedInternalName mkWorkerOcc uniq (getName unwrkr)) ty
 
+mkLoopId :: Id -> Id
+mkLoopId i
+  = mkLocalIdOrCoVar (mkDerivedInternalName mkLoopOcc (getUnique i) (getName i)) (idType i)
+
 -- | Create a /template local/: a family of system local 'Id's in bijection with @Int at s, typically used in unfoldings
 mkTemplateLocal :: Int -> Type -> Id
 mkTemplateLocal i ty = mkSysLocalOrCoVar (fsLit "v") (mkBuiltinUnique i) ty
diff --git a/compiler/basicTypes/OccName.hs b/compiler/basicTypes/OccName.hs
index f6a66fd..f95b608 100644
--- a/compiler/basicTypes/OccName.hs
+++ b/compiler/basicTypes/OccName.hs
@@ -61,7 +61,7 @@ module OccName (
         mkNewTyCoOcc, mkClassOpAuxOcc,
         mkCon2TagOcc, mkTag2ConOcc, mkMaxTagOcc,
         mkClassDataConOcc, mkDictOcc, mkIPOcc,
-        mkSpecOcc, mkForeignExportOcc, mkRepEqOcc,
+        mkSpecOcc, mkLoopOcc, mkForeignExportOcc, mkRepEqOcc,
         mkGenR, mkGen1R,
         mkDataTOcc, mkDataCOcc, mkDataConWorkerOcc,
         mkSuperDictSelOcc, mkSuperDictAuxOcc,
@@ -615,7 +615,7 @@ mkDataConWrapperOcc, mkWorkerOcc,
         mkMatcherOcc, mkBuilderOcc,
         mkDefaultMethodOcc,
         mkClassDataConOcc, mkDictOcc,
-        mkIPOcc, mkSpecOcc, mkForeignExportOcc, mkRepEqOcc,
+        mkIPOcc, mkSpecOcc, mkLoopOcc, mkForeignExportOcc, mkRepEqOcc,
         mkGenR, mkGen1R,
         mkDataConWorkerOcc, mkNewTyCoOcc,
         mkInstTyCoOcc, mkEqPredCoOcc, mkClassOpAuxOcc,
@@ -633,6 +633,7 @@ mkClassOpAuxOcc     = mk_simple_deriv varName  "$c"
 mkDictOcc           = mk_simple_deriv varName  "$d"
 mkIPOcc             = mk_simple_deriv varName  "$i"
 mkSpecOcc           = mk_simple_deriv varName  "$s"
+mkLoopOcc           = mk_simple_deriv varName  "$l"
 mkForeignExportOcc  = mk_simple_deriv varName  "$f"
 mkRepEqOcc          = mk_simple_deriv tvName   "$r"   -- In RULES involving Coercible
 mkClassDataConOcc   = mk_simple_deriv dataName "C:"     -- Data con for a class
diff --git a/compiler/coreSyn/CoreOpt.hs b/compiler/coreSyn/CoreOpt.hs
index 57812e4..7012d5b 100644
--- a/compiler/coreSyn/CoreOpt.hs
+++ b/compiler/coreSyn/CoreOpt.hs
@@ -673,7 +673,7 @@ loopificationJoinPointBinding_maybe bndr rhs
         join_bndr = (`asJoinId` join_arity) $
                      (`setIdOccInfo` occ') $
                      zapFragileIdInfo $
-                     localiseId $
+                     mkLoopId $
                      bndr
         -- RULES etc stay with bindr'
         bndr' = zapIdTailCallInfo bndr


From git at git.haskell.org  Mon Mar 19 19:22:03 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 19 Mar 2018 19:22:03 +0000 (UTC)
Subject: [commit: ghc] wip/T14068: SpecConstr: Also create specializations for
 top-level non-recursive functions (d8165f2)
Message-ID: <20180319192203.63CEE3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/T14068
Link       : http://ghc.haskell.org/trac/ghc/changeset/d8165f268a4c7a5b23bb84b2136c09ab3bd8383d/ghc

>---------------------------------------------------------------

commit d8165f268a4c7a5b23bb84b2136c09ab3bd8383d
Author: Joachim Breitner <mail at joachim-breitner.de>
Date:   Mon Mar 19 15:20:24 2018 -0400

    SpecConstr: Also create specializations for top-level non-recursive functions
    
    See #14844


>---------------------------------------------------------------

d8165f268a4c7a5b23bb84b2136c09ab3bd8383d
 compiler/specialise/SpecConstr.hs | 30 ++++++++++++++++++++----------
 1 file changed, 20 insertions(+), 10 deletions(-)

diff --git a/compiler/specialise/SpecConstr.hs b/compiler/specialise/SpecConstr.hs
index d54c1ea..9549b3c 100644
--- a/compiler/specialise/SpecConstr.hs
+++ b/compiler/specialise/SpecConstr.hs
@@ -722,9 +722,9 @@ specConstrProgram guts
 
     -- Arg list of bindings is in reverse order
     go _   _   []           = return []
-    go env usg (bind:binds) = do (usg', bind') <- scTopBind env usg bind
+    go env usg (bind:binds) = do (usg', these_binds') <- scTopBind env usg bind
                                  binds' <- go env usg' binds
-                                 return (bind' : binds')
+                                 return (reverse these_binds' ++ binds')
 
 {-
 ************************************************************************
@@ -1392,11 +1392,12 @@ scTopBindEnv env (Rec prs)
 
 scTopBindEnv env (NonRec bndr rhs)
   = do  { let (env1, bndr') = extendBndr env bndr
-              env2          = extendValEnv env1 bndr' (isValue (sc_vals env) rhs)
-        ; return (env2, NonRec bndr' rhs) }
+              env2          = extendHowBound env1 [bndr] RecFun
+              env3          = extendValEnv env2 bndr' (isValue (sc_vals env) rhs)
+        ; return (env3, NonRec bndr' rhs) }
 
 ----------------------
-scTopBind :: ScEnv -> ScUsage -> CoreBind -> UniqSM (ScUsage, CoreBind)
+scTopBind :: ScEnv -> ScUsage -> CoreBind -> UniqSM (ScUsage, [CoreBind])
 
 {-
 scTopBind _ usage _
@@ -1411,7 +1412,8 @@ scTopBind env body_usage (Rec prs)
                 -- No specialisation
   = -- pprTrace "scTopBind: nospec" (ppr bndrs) $
     do  { (rhs_usgs, rhss')   <- mapAndUnzipM (scExpr env) rhss
-        ; return (body_usage `combineUsage` combineUsages rhs_usgs, Rec (bndrs `zip` rhss')) }
+        ; return (body_usage `combineUsage` combineUsages rhs_usgs,
+                  [Rec (bndrs `zip` rhss')]) }
 
   | otherwise   -- Do specialisation
   = do  { rhs_infos <- mapM (scRecRhs env) prs
@@ -1420,15 +1422,23 @@ scTopBind env body_usage (Rec prs)
                                          body_usage rhs_infos
 
         ; return (body_usage `combineUsage` spec_usage,
-                  Rec (concat (zipWith ruleInfoBinds rhs_infos specs))) }
+                  [Rec (concat (zipWith ruleInfoBinds rhs_infos specs))]) }
   where
     (bndrs,rhss) = unzip prs
     force_spec   = any (forceSpecBndr env) bndrs
       -- Note [Forcing specialisation]
 
-scTopBind env usage (NonRec bndr rhs)   -- Oddly, we don't seem to specialise top-level non-rec functions
-  = do  { (rhs_usg', rhs') <- scExpr env rhs
-        ; return (usage `combineUsage` rhs_usg', NonRec bndr rhs') }
+scTopBind env body_usage (NonRec bndr rhs)
+  = do  { rhs_info  <- scRecRhs env (bndr,rhs)
+
+        ; (spec_usg, specs) <- specNonRec env body_usage rhs_info
+
+        ; let binds' = [NonRec b r | (b,r) <- ruleInfoBinds rhs_info specs]
+
+        ; return (body_usage `combineUsage` spec_usg, binds')
+        }
+
+
 
 ----------------------
 scRecRhs :: ScEnv -> (OutId, InExpr) -> UniqSM RhsInfo


From git at git.haskell.org  Mon Mar 19 19:22:06 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 19 Mar 2018 19:22:06 +0000 (UTC)
Subject: [commit: ghc] wip/T14068: Run SpecConstr twice,
 simplify in between (bdb92ef)
Message-ID: <20180319192206.2E9433A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/T14068
Link       : http://ghc.haskell.org/trac/ghc/changeset/bdb92ef065f117f64e9ea86720b9297d9abe567a/ghc

>---------------------------------------------------------------

commit bdb92ef065f117f64e9ea86720b9297d9abe567a
Author: Joachim Breitner <mail at joachim-breitner.de>
Date:   Mon Mar 19 15:20:57 2018 -0400

    Run SpecConstr twice, simplify in between
    
    otherwise, it does not see that certain arguments are actually useful to
    be specialized to. This gets x2n1 performance on par.


>---------------------------------------------------------------

bdb92ef065f117f64e9ea86720b9297d9abe567a
 compiler/simplCore/SimplCore.hs | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/compiler/simplCore/SimplCore.hs b/compiler/simplCore/SimplCore.hs
index 0a20eb0..9f260a6 100644
--- a/compiler/simplCore/SimplCore.hs
+++ b/compiler/simplCore/SimplCore.hs
@@ -344,6 +344,10 @@ getCoreToDo dflags
 
         runWhen spec_constr CoreDoSpecConstr,
 
+        simpl_phase 0 ["between-core-spec"] max_iter,
+
+        runWhen spec_constr CoreDoSpecConstr,
+
         maybe_rule_check (Phase 0),
 
         -- Final clean-up simplification:


From git at git.haskell.org  Mon Mar 19 19:22:08 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 19 Mar 2018 19:22:08 +0000 (UTC)
Subject: [commit: ghc] wip/T14068's head updated: Run SpecConstr twice,
 simplify in between (bdb92ef)
Message-ID: <20180319192208.F101D3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

Branch 'wip/T14068' now includes:

     0c9777b Fix tests broken by c9a88db3ac4f1c3e97e3492ebe076f2df6463540
     8936ab6 Raise parse error for `data T where`.
     df449e1 Various documentation improvements
     ec9aacf adds -latomic to. ghc-prim
     d5ff33d Adds `smp` flag to rts.cabal.
     e03ca71 Update .cabal files for Cabal 2.1
     0c2350c rts.cabal.in: advertise profiling flavours of libraries, behind a flag
     8529fbb Get eqTypeRep to inline
     7c173b9 Move `iserv` into `utils` and change package name from `iserv-bin` to `iserv`
     d5ac582 Fix #14811 by wiring in $tcUnit#
     a644dff circleci: Add nightly build using devel2 flavour
     9080466 base: Fix changelog entry for openTempFile
     1ede46d Implement stopgap solution for #14728
     918c0b3 Add valid refinement substitution suggestions for typed holes
     9ff4cce Build Haddocks with --quickjump
     bfb90bc Remove doubled words
     ccda486 Tidy up and consolidate canned CmmReg and CmmGlobals
     c05529c myThreadId# is trivial; make it an inline primop
     4e513bf CBE: re-introduce bgamari's fixes
     d924c17 testsuite: Add newline to test output
     fc33f8b Improve error message for UNPACK/strictness annotations.
     7f389a5 StgLint overhaul
     043466b Rename the types in a GADT constructor in toposorted order
     5b63240 Increase the amount of parallelism in circleci.
     9fc4608 Bump haddock submodule again
     2382bbf Bump process submodule
     fc04a8f Bump filepath submodule
     d20524e Bump pretty submodule
     9ad3fa1 Bump stm submodule to 2.4.5.0
     bd0af2a Bump primitive submodule to 0.6.3.0
     e26d774 Bump parsec submodule to 0.3.13.0
     1ee5abc Bump haskeline submodule to 0.7.4.2
     2cb19b4 Bump text submodule to 1.2.3.0
     71294f3 testsuite: Bump allocations for T1969 and T5837
     eb2daa2 Change how includes for input file directory works
     517c194 Document missing dataToTag# . tagToEnum# rule
     81a5e05 circleci: Skip performance tests
     f511bb5 Add ghc-prim.buildinfo to .gitignore
     f433659 Slight refactor of stock deriving internals
     abfe104 Revert "Move `iserv` into `utils` and change package name
     a032ff7 Add references to #6087
     0a3629a Don't use ld.gold when building libraries for GHCi
     3483423 Comments in Unify, fixing #12442
     bf3f0a6 Update Hadrian submodule
     c969c98 driver/utils/dynwrapper.c: Remove unused variable
     be498a2 RTS: Remember to free some pointers
     cb89ba8 RTS: Remove unused retainer schemes
     3d43fd5 Introduce the flag -dsuppress-timestamps to avoid timestamps in dumps.
     5e5e60d boot: Create GNUmakefiles for libraries
     f57c305 testsuite: Bump allocations for T9630
     ffdb110 Update .gitignore
     da4766c circleci: Simplify Hadrian build
     8c1d6b7 Tiny refactor in Core Lint
     40fa420 Comments only
     e99fdf7 Fix a nasty bug in the pure unifier
     d675a35 Better stats for T5837
     3dec923 Test for Trac #13075 is working now
     51e0a38 Comments only
     b2996f1 Fix test for Trac #13075
     df2c3b3 Build quick flavor and run some tests on Windows
     2756117 Revert "Better stats for T5837"
     b8f03bb Cache the fingerprint of sOpt_P
     e261b85 forkProcess: fix task mutex release order
     8dab89b rts: Note functions which must take all_tasks_mutex.
     f8e3cd3 Only load plugins once
     d8e47a2 Make cost centre symbol names deterministic.
     8c7a155 Move Data.Functor.Contravariant from the contravariant package to base.
     e8e9f6a Improve exhaustive checking for guards in pattern bindings and MultiIf.
     125d151 Add regression test for #12790
     aef2b42 Fix #14817 by not double-printing data family instance kind signatures
     4a0d0d8 Various Windows / Cross Compile to Windows fixes
     1773964 DynFlags: Support British spelling of GeneralisedNewtypeDeriving
     969e747 GHCi info: Use src file for cache invalidation
     6a7e159 Improve missing-home-modules warning formatting
     5c28ee8 Add @since annotations for derived instances in base
     6e4fa81 rts/win32: Assert that the IO manager has been initialised
     bc1bcaa configure: Enable LD_NO_GOLD is set in all codepaths
     7782b47 Add Applicative, Semigroup, and Monoid instances in GHC.Generics
     e4dcebf Adds *-cross-ncg flavour.
     6835702 Permit conversion of partially applied PromotedTupleTs
     ffb2738 Fix #14838 by marking TH-spliced code as FromSource
     5f6fcf7 Compile with `--via-asm` when cross compiling.
     44ba60f doCorePass: Expand catch-all
     821daad Correct default -A value in RTS flag usage info
     a2d03c6 Fix the coverage checker's treatment of existential tyvars
     99c556d Parenthesize (() :: Constraint) in argument position
     4631ceb Bump hsc2hs submodule
     8f0b2f5 Bump Cabal submodule to 2.2
     a9f680f Bump Cabal submodule
     e7653bc Wombling around in Trac #14808
     3d25203 Respect Note [The tcType invariant]
     6ee831f Fix #14888 by adding more special cases for ArrowT
     1c062b7 Simplify rnLHsInstType
     df7ac37 Fixup include of gmp/config.mk to use new location
     f6cf400 `--via-asm` only for windows targets
     cf5bc96 add CCX=$(CXX) to integer-gmp
     ee597e9 Schedule.c: remove a redundant CPP guard
     5bc195a Allow top level ticked string literals
     9bccfcd Correct -g flag description
     64c0af7 cmm/: Avoid using lazy left folds
     08345bd Make accumArray and accum stricter
     1488591 Bump nofib submodule
     488d63d Fix interpreter with profiling
     40c4313 Add perf test for #14052
     b120e64 Add bindist-list.uniq to .gitignore
     d9d4632 Schedule.c: remove unreachable code block
     648cb28 Use docker images with non-root user
     b320ba8 Fix a typo about pattern synonyms in documentation.
     b3bfbed Users Guide: Add that --numa is available on Windows too
     43fbb90 Fix typo in description of -V RTS flag
     d99a65a Add -fexternal-dynamic-refs
     98c7749 Revert "GHCi: Don't remove shadowed bindings from typechecker scope."
     bc95fed Error message and doc improvements for #14335
     ed6f9fb ghc-prim: Reduce scope of Clang sync_fetch_and_nand workaround
     94f0254 ghc-prim: Silence -Wsync-nand warning in atomic.c
     47e2a28 Remove outdated documentation bits concerning -Wmissing-methods
     a25b763 configure: Accept suffix in OpenBSD triple's OS name
     df2ea10 Compacted arrays are pinned for isByteArrayPinned#
     dd3906b UNREG: fix implicit declarations from pdep and pext
     8e34101 Fix a debug print in disassembler (#14905)
     e3ae0eb testsuite: disable T13615 on non-smp targets
     5c804e5 Remove splitEithers, use partitionEithers from base
     02b3dad Bump Cabal submodule
     50972d6 Comment improvements on interpreter breakpoint IO action
     ba57979 Update a comment in Exception.cmm
     152055a Drop GHC 8.0 compatibility
     cb6d858 Slighly improve infix con app pattern errors
     1522cf0 aclocal.m4: allow more GNU/Hurd tuples
     0693b0b aclocal.m4: add OSHurd (debian patch)
     4ba3bd7 Require GHC 8.2 to bootstrap GHC
     9c6785b Merge branch 'master' into wip/T14068
     9245c4b Prefix the loopification name with $l
     d8165f2 SpecConstr: Also create specializations for top-level non-recursive functions
     bdb92ef Run SpecConstr twice, simplify in between

From git at git.haskell.org  Mon Mar 19 20:46:38 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 19 Mar 2018 20:46:38 +0000 (UTC)
Subject: [commit: ghc] master: rts,
 base: Refactor stats.c to improve --machine-readable report (2d4bda2)
Message-ID: <20180319204638.758343A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/2d4bda2e4ac68816baba0afab00da6f769ea75a7/ghc

>---------------------------------------------------------------

commit 2d4bda2e4ac68816baba0afab00da6f769ea75a7
Author: Douglas Wilson <douglas.wilson at gmail.com>
Date:   Mon Mar 19 13:26:41 2018 -0400

    rts, base: Refactor stats.c to improve --machine-readable report
    
    There should be no change in the output of the '+RTS -s' (summary)
    report, or the 'RTS -t' (one-line) report.
    
    All data shown in the summary report is now shown in the machine
    readable report.
    
    All data in RTSStats is now shown in the machine readable report.
    
    init times are added to RTSStats and added to GHC.Stats.
    
    Example of the new output:
    ```
     [("bytes allocated", "375016384")
     ,("num_GCs", "113")
     ,("average_bytes_used", "148348")
     ,("max_bytes_used", "206552")
     ,("num_byte_usage_samples", "2")
     ,("peak_megabytes_allocated", "6")
     ,("init_cpu_seconds", "0.001642")
     ,("init_wall_seconds", "0.001027")
     ,("mut_cpu_seconds", "3.020166")
     ,("mut_wall_seconds", "0.757244")
     ,("GC_cpu_seconds", "0.037750")
     ,("GC_wall_seconds", "0.009569")
     ,("exit_cpu_seconds", "0.000890")
     ,("exit_wall_seconds", "0.002551")
     ,("total_cpu_seconds", "3.060452")
     ,("total_wall_seconds", "0.770395")
     ,("major_gcs", "2")
     ,("allocated_bytes", "375016384")
     ,("max_live_bytes", "206552")
     ,("max_large_objects_bytes", "159344")
     ,("max_compact_bytes", "0")
     ,("max_slop_bytes", "59688")
     ,("max_mem_in_use_bytes", "6291456")
     ,("cumulative_live_bytes", "296696")
     ,("copied_bytes", "541024")
     ,("par_copied_bytes", "493976")
     ,("cumulative_par_max_copied_bytes", "104104")
     ,("cumulative_par_balanced_copied_bytes", "274456")
     ,("fragmentation_bytes", "2112")
     ,("alloc_rate", "124170795")
     ,("productivity_cpu_percent", "0.986838")
     ,("productivity_wall_percent", "0.982935")
     ,("bound_task_count", "1")
     ,("sparks_count", "5836258")
     ,("sparks_converted", "237")
     ,("sparks_overflowed", "1990408")
     ,("sparks_dud ", "0")
     ,("sparks_gcd", "3455553")
     ,("sparks_fizzled", "390060")
     ,("work_balance", "0.555606")
     ,("n_capabilities", "4")
     ,("task_count", "10")
     ,("peak_worker_count", "9")
     ,("worker_count", "9")
     ,("gc_alloc_block_sync_spin", "162")
     ,("gc_alloc_block_sync_yield", "0")
     ,("gc_alloc_block_sync_spin", "162")
     ,("gc_spin_spin", "18840855")
     ,("gc_spin_yield", "10355")
     ,("mut_spin_spin", "70331392")
     ,("mut_spin_yield", "61700")
     ,("waitForGcThreads_spin", "241")
     ,("waitForGcThreads_yield", "2797")
     ,("whitehole_gc_spin", "0")
     ,("whitehole_lockClosure_spin", "0")
     ,("whitehole_lockClosure_yield", "0")
     ,("whitehole_executeMessage_spin", "0")
     ,("whitehole_threadPaused_spin", "0")
     ,("any_work", "1667")
     ,("no_work", "1662")
     ,("scav_find_work", "1026")
     ,("gen_0_collections", "111")
     ,("gen_0_par_collections", "111")
     ,("gen_0_cpu_seconds", "0.036126")
     ,("gen_0_wall_seconds", "0.036126")
     ,("gen_0_max_pause_seconds", "0.036126")
     ,("gen_0_avg_pause_seconds", "0.000081")
     ,("gen_0_sync_spin", "21")
     ,("gen_0_sync_yield", "0")
     ,("gen_1_collections", "2")
     ,("gen_1_par_collections", "1")
     ,("gen_1_cpu_seconds", "0.001624")
     ,("gen_1_wall_seconds", "0.001624")
     ,("gen_1_max_pause_seconds", "0.001624")
     ,("gen_1_avg_pause_seconds", "0.000272")
     ,("gen_1_sync_spin", "3")
     ,("gen_1_sync_yield", "0")
     ]
    ```
    
    Test Plan: Ensure that one-line and summary reports are unchanged.
    
    Reviewers: bgamari, erikd, simonmar, hvr
    
    Reviewed By: simonmar
    
    Subscribers: rwbarton, thomie, carter
    
    GHC Trac Issues: #14660
    
    Differential Revision: https://phabricator.haskell.org/D4303


>---------------------------------------------------------------

2d4bda2e4ac68816baba0afab00da6f769ea75a7
 includes/RtsAPI.h            |  34 +-
 libraries/base/GHC/Stats.hsc |   8 +
 rts/Stats.c                  | 921 +++++++++++++++++++++++++++++--------------
 rts/Stats.h                  |  45 +++
 4 files changed, 691 insertions(+), 317 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc 2d4bda2e4ac68816baba0afab00da6f769ea75a7

From git at git.haskell.org  Mon Mar 19 20:46:51 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 19 Mar 2018 20:46:51 +0000 (UTC)
Subject: [commit: ghc] master: Add -flate-specialise which runs a later
 specialisation pass (afad556)
Message-ID: <20180319204651.D47FA3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/afad5561d88f04744c398ef0640d846db6262aa0/ghc

>---------------------------------------------------------------

commit afad5561d88f04744c398ef0640d846db6262aa0
Author: Matthew Pickering <matthewtpickering at gmail.com>
Date:   Mon Mar 19 13:29:14 2018 -0400

    Add -flate-specialise which runs a later specialisation pass
    
    Runs another specialisation pass towards the end of the optimisation
    pipeline. This can catch specialisation opportunities which arose from
    the previous specialisation pass or other inlining.
    
    You might want to use this if you are you have a type class method
    which returns a constrained type. For example, a type class where one
    of the methods implements a traversal.
    
    It is not enabled by default or any optimisation level. Only by
    manually enabling the flag `-flate-specialise`.
    
    Reviewers: bgamari
    
    Reviewed By: bgamari
    
    Subscribers: rwbarton, thomie, carter
    
    Differential Revision: https://phabricator.haskell.org/D4457


>---------------------------------------------------------------

afad5561d88f04744c398ef0640d846db6262aa0
 compiler/main/DynFlags.hs               |  3 +++
 compiler/simplCore/SimplCore.hs         |  5 +++++
 docs/users_guide/using-optimisation.rst | 14 ++++++++++++++
 3 files changed, 22 insertions(+)

diff --git a/compiler/main/DynFlags.hs b/compiler/main/DynFlags.hs
index f9d2bfb..0d018a7 100644
--- a/compiler/main/DynFlags.hs
+++ b/compiler/main/DynFlags.hs
@@ -450,6 +450,7 @@ data GeneralFlag
    | Opt_KillOneShot
    | Opt_FullLaziness
    | Opt_FloatIn
+   | Opt_LateSpecialise
    | Opt_Specialise
    | Opt_SpecialiseAggressively
    | Opt_CrossModuleSpecialise
@@ -633,6 +634,7 @@ optimisationFlags = EnumSet.fromList
    , Opt_KillOneShot
    , Opt_FullLaziness
    , Opt_FloatIn
+   , Opt_LateSpecialise
    , Opt_Specialise
    , Opt_SpecialiseAggressively
    , Opt_CrossModuleSpecialise
@@ -3937,6 +3939,7 @@ fFlagsDeps = [
   flagSpec "kill-absence"                     Opt_KillAbsence,
   flagSpec "kill-one-shot"                    Opt_KillOneShot,
   flagSpec "late-dmd-anal"                    Opt_LateDmdAnal,
+  flagSpec "late-specialise"                  Opt_LateSpecialise,
   flagSpec "liberate-case"                    Opt_LiberateCase,
   flagSpec "llvm-pass-vectors-in-regs"        Opt_LlvmPassVectorsInRegisters,
   flagHiddenSpec "llvm-tbaa"                  Opt_LlvmTBAA,
diff --git a/compiler/simplCore/SimplCore.hs b/compiler/simplCore/SimplCore.hs
index bf69964..61622ae 100644
--- a/compiler/simplCore/SimplCore.hs
+++ b/compiler/simplCore/SimplCore.hs
@@ -131,6 +131,7 @@ getCoreToDo dflags
     spec_constr   = gopt Opt_SpecConstr                   dflags
     liberate_case = gopt Opt_LiberateCase                 dflags
     late_dmd_anal = gopt Opt_LateDmdAnal                  dflags
+    late_specialise = gopt Opt_LateSpecialise             dflags
     static_args   = gopt Opt_StaticArgumentTransformation dflags
     rules_on      = gopt Opt_EnableRewriteRules           dflags
     eta_expand_on = gopt Opt_DoLambdaEtaExpansion         dflags
@@ -347,6 +348,10 @@ getCoreToDo dflags
 
         maybe_rule_check (Phase 0),
 
+        runWhen late_specialise
+          (CoreDoPasses [ CoreDoSpecialising
+                        , simpl_phase 0 ["post-late-spec"] max_iter]),
+
         -- Final clean-up simplification:
         simpl_phase 0 ["final"] max_iter,
 
diff --git a/docs/users_guide/using-optimisation.rst b/docs/users_guide/using-optimisation.rst
index 3566462..d6c24de 100644
--- a/docs/users_guide/using-optimisation.rst
+++ b/docs/users_guide/using-optimisation.rst
@@ -884,6 +884,20 @@ by saying ``-fno-wombat``.
     which they are called in this module. Note that specialisation must be
     enabled (by ``-fspecialise``) for this to have any effect.
 
+.. ghc-flag:: -flate-specialise
+    :shortdesc: Run a late specialisation pass
+    :type: dynamic
+    :reverse: -fno-late-specialise
+    :default: off
+
+    Runs another specialisation pass towards the end of the optimisation
+    pipeline. This can catch specialisation opportunities which arose from
+    the previous specialisation pass or other inlining.
+
+    You might want to use this if you are you have a type class method
+    which returns a constrained type. For example, a type class where one
+    of the methods implements a traversal.
+
 .. ghc-flag:: -fsolve-constant-dicts
     :shortdesc: When solving constraints, try to eagerly solve
         super classes using available dictionaries.


From git at git.haskell.org  Mon Mar 19 20:47:06 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 19 Mar 2018 20:47:06 +0000 (UTC)
Subject: [commit: ghc] master: Bump autoconf version bound to >= 2.69 (6a71ef7)
Message-ID: <20180319204706.A2EA03A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/6a71ef79cffbfbf09f1567d0136711d80452eb41/ghc

>---------------------------------------------------------------

commit 6a71ef79cffbfbf09f1567d0136711d80452eb41
Author: Ben Gamari <bgamari.foss at gmail.com>
Date:   Mon Mar 19 13:31:31 2018 -0400

    Bump autoconf version bound to >= 2.69
    
    Reviewers: hvr
    
    Subscribers: rwbarton, thomie, erikd, carter
    
    GHC Trac Issues: #14910
    
    Differential Revision: https://phabricator.haskell.org/D4495


>---------------------------------------------------------------

6a71ef79cffbfbf09f1567d0136711d80452eb41
 configure.ac                       | 15 ++++++++-------
 distrib/configure.ac.in            |  3 +++
 libraries/integer-gmp/configure.ac |  2 +-
 3 files changed, 12 insertions(+), 8 deletions(-)

diff --git a/configure.ac b/configure.ac
index e75fc6c..1bab56d 100644
--- a/configure.ac
+++ b/configure.ac
@@ -55,13 +55,14 @@ AC_SUBST([release], [1])
 # First off, a distrib sanity check..
 AC_CONFIG_SRCDIR([mk/config.mk.in])
 
-dnl * We require autoconf version 2.60
-dnl We need 2.50 due to the use of AC_SYS_LARGEFILE and AC_MSG_NOTICE.
-dnl We need 2.52 due to the use of AS_TR_CPP and AS_TR_SH.
-dnl Using autoconf 2.59 started to give nonsense like this
-dnl  #define SIZEOF_CHAR 0
-dnl recently.
-AC_PREREQ([2.60])
+dnl * We require autoconf version 2.69 due to
+dnl   https://bugs.ruby-lang.org/issues/8179. Also see #14910.
+dnl * We need 2.50 due to the use of AC_SYS_LARGEFILE and AC_MSG_NOTICE.
+dnl * We need 2.52 due to the use of AS_TR_CPP and AS_TR_SH.
+dnl * Using autoconf 2.59 started to give nonsense like this
+dnl     #define SIZEOF_CHAR 0
+dnl   recently.
+AC_PREREQ([2.69])
 
 # -------------------------------------------------------------------------
 # Prepare to generate the following header files
diff --git a/distrib/configure.ac.in b/distrib/configure.ac.in
index 95ad198..ed1c296 100644
--- a/distrib/configure.ac.in
+++ b/distrib/configure.ac.in
@@ -6,6 +6,9 @@ dnl
 
 AC_INIT([The Glorious Glasgow Haskell Compilation System], [@ProjectVersion@], [glasgow-haskell-bugs at haskell.org], [ghc-AC_PACKAGE_VERSION])
 
+dnl See /configure.ac for rationale.
+AC_PREREQ([2.69])
+
 dnl--------------------------------------------------------------------
 dnl * Deal with arguments telling us gmp is somewhere odd
 dnl--------------------------------------------------------------------
diff --git a/libraries/integer-gmp/configure.ac b/libraries/integer-gmp/configure.ac
index c19dbbc..3aebeba 100644
--- a/libraries/integer-gmp/configure.ac
+++ b/libraries/integer-gmp/configure.ac
@@ -1,4 +1,4 @@
-AC_PREREQ(2.60)
+AC_PREREQ(2.69)
 AC_INIT([Haskell integer (GMP)], [1.0], [libraries at haskell.org], [integer])
 
 # Safety check: Ensure that we are in the correct source directory.


From git at git.haskell.org  Mon Mar 19 20:47:22 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 19 Mar 2018 20:47:22 +0000 (UTC)
Subject: [commit: ghc] master: relnotes: Fix parsing of Version: field from
 Cabal file (d718023)
Message-ID: <20180319204722.0D55E3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/d718023e86c8681b87f212bd64eb6ca10ac8935e/ghc

>---------------------------------------------------------------

commit d718023e86c8681b87f212bd64eb6ca10ac8935e
Author: Ben Gamari <bgamari.foss at gmail.com>
Date:   Mon Mar 19 13:31:46 2018 -0400

    relnotes: Fix parsing of Version: field from Cabal file
    
    Subscribers: rwbarton, thomie, carter
    
    Differential Revision: https://phabricator.haskell.org/D4491


>---------------------------------------------------------------

d718023e86c8681b87f212bd64eb6ca10ac8935e
 docs/users_guide/ghc_packages.py | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/docs/users_guide/ghc_packages.py b/docs/users_guide/ghc_packages.py
index d4a688b..6419834 100644
--- a/docs/users_guide/ghc_packages.py
+++ b/docs/users_guide/ghc_packages.py
@@ -8,13 +8,13 @@ from utils import build_table_from_list
 def read_cabal_file(pkg_path):
     import re
     cabal_file = open(pkg_path, 'r').read()
-    pkg_name = re.search(r'[nN]ame:\s*([-a-zA-Z0-9]+)', cabal_file)
+    pkg_name = re.search(r'^[nN]ame\s*:\s*([-a-zA-Z0-9]+)', cabal_file, re.MULTILINE)
     if pkg_name is not None:
         pkg_name = pkg_name.group(1)
     else:
         raise RuntimeError("Failed to parse `Name:` field from %s" % pkg_path)
 
-    pkg_version = re.search(r'[vV]ersion:\s*(\d+(\.\d+)*)', cabal_file)
+    pkg_version = re.search(r'^[vV]ersion\s*:\s*(\d+(\.\d+)*)', cabal_file, re.MULTILINE)
     if pkg_version is not None:
         pkg_version = pkg_version.group(1)
     else:


From git at git.haskell.org  Mon Mar 19 20:47:35 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 19 Mar 2018 20:47:35 +0000 (UTC)
Subject: [commit: ghc] master: configure: Accept version suffix in solaris
 name (60aa53d)
Message-ID: <20180319204735.1CBB73A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/60aa53d97da1bbfbb88e9f2791c3f686ba34e764/ghc

>---------------------------------------------------------------

commit 60aa53d97da1bbfbb88e9f2791c3f686ba34e764
Author: Ben Gamari <bgamari.foss at gmail.com>
Date:   Mon Mar 19 13:32:14 2018 -0400

    configure: Accept version suffix in solaris name
    
    Summary: OpenIndiana apparently reports a triple of i386-pc-solaris2.11.
    
    Reviewers: hvr
    
    Subscribers: rwbarton, thomie, erikd, carter
    
    Differential Revision: https://phabricator.haskell.org/D4487


>---------------------------------------------------------------

60aa53d97da1bbfbb88e9f2791c3f686ba34e764
 aclocal.m4 | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/aclocal.m4 b/aclocal.m4
index 58d43e1..e19cbf2 100644
--- a/aclocal.m4
+++ b/aclocal.m4
@@ -1970,7 +1970,7 @@ AC_DEFUN([GHC_CONVERT_OS],[
         $3="openbsd"
         ;;
       # As far as I'm aware, none of these have relevant variants
-      freebsd|netbsd|dragonfly|hpux|linuxaout|kfreebsdgnu|freebsd2|solaris2|mingw32|darwin|nextstep2|nextstep3|sunos4|ultrix|haiku)
+      freebsd|netbsd|dragonfly|hpux|linuxaout|kfreebsdgnu|freebsd2|mingw32|darwin|nextstep2|nextstep3|sunos4|ultrix|haiku)
         $3="$1"
         ;;
       aix*) # e.g. powerpc-ibm-aix7.1.3.0
@@ -1979,6 +1979,9 @@ AC_DEFUN([GHC_CONVERT_OS],[
       darwin*) # e.g. aarch64-apple-darwin14
         $3="darwin"
         ;;
+      solaris2*)
+        $3="solaris2"
+        ;;
       freebsd*) # like i686-gentoo-freebsd7
                 #      i686-gentoo-freebsd8
                 #      i686-gentoo-freebsd8.2


From git at git.haskell.org  Mon Mar 19 20:54:43 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 19 Mar 2018 20:54:43 +0000 (UTC)
Subject: [commit: ghc] wip/T14068: In scTopBind NonRec,
 do not forget the usage from the rhs_info (0f1fee6)
Message-ID: <20180319205443.B23CD3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/T14068
Link       : http://ghc.haskell.org/trac/ghc/changeset/0f1fee6be3df20837543ede7223a827abb6a4759/ghc

>---------------------------------------------------------------

commit 0f1fee6be3df20837543ede7223a827abb6a4759
Author: Joachim Breitner <mail at joachim-breitner.de>
Date:   Mon Mar 19 16:54:06 2018 -0400

    In scTopBind NonRec, do not forget the usage from the rhs_info
    
    not that I know what I am doing here, but this seems to work “better”


>---------------------------------------------------------------

0f1fee6be3df20837543ede7223a827abb6a4759
 compiler/specialise/SpecConstr.hs | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/compiler/specialise/SpecConstr.hs b/compiler/specialise/SpecConstr.hs
index 9549b3c..efd56ce 100644
--- a/compiler/specialise/SpecConstr.hs
+++ b/compiler/specialise/SpecConstr.hs
@@ -1433,9 +1433,12 @@ scTopBind env body_usage (NonRec bndr rhs)
 
         ; (spec_usg, specs) <- specNonRec env body_usage rhs_info
 
+        ; let usage' = body_usage `combineUsage` spec_usg `combineUsage` ri_rhs_usg rhs_info
+
         ; let binds' = [NonRec b r | (b,r) <- ruleInfoBinds rhs_info specs]
 
-        ; return (body_usage `combineUsage` spec_usg, binds')
+
+        ; return (usage', binds')
         }
 
 


From git at git.haskell.org  Tue Mar 20 07:50:01 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 20 Mar 2018 07:50:01 +0000 (UTC)
Subject: [commit: ghc] master: Update T5129 test: (57001d9)
Message-ID: <20180320075001.9F5DB3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/57001d93da7b50a58e67a712bd4d4cee1d004b6a/ghc

>---------------------------------------------------------------

commit 57001d93da7b50a58e67a712bd4d4cee1d004b6a
Author: Ömer Sinan Ağacan <omeragacan at gmail.com>
Date:   Tue Mar 20 10:48:14 2018 +0300

    Update T5129 test:
    
    - Add some comments
    - Remove $s as they complicate desugarer output for no reason
    - Remove an indirection, case_negative is now main


>---------------------------------------------------------------

57001d93da7b50a58e67a712bd4d4cee1d004b6a
 testsuite/tests/codeGen/should_run/T5129.hs | 11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/testsuite/tests/codeGen/should_run/T5129.hs b/testsuite/tests/codeGen/should_run/T5129.hs
index 6bc1912..2808f54 100644
--- a/testsuite/tests/codeGen/should_run/T5129.hs
+++ b/testsuite/tests/codeGen/should_run/T5129.hs
@@ -10,12 +10,13 @@ throwIfNegative n | n < 0     = error "negative"
 data HUnitFailure = HUnitFailure String deriving (Show,Typeable)
 instance Exception HUnitFailure
 
+assertFailure :: String -> a -- Not an IO function!
 assertFailure msg = E.throw (HUnitFailure msg)
 
-case_negative =
-    handleJust errorCalls (const $ return ()) $ do
-        evaluate $ throwIfNegative (-1)
-        assertFailure "must throw when given a negative number"
+main :: IO ()
+main =
+    handleJust errorCalls (const (return ())) (do
+        evaluate (throwIfNegative (-1)) -- Pure expression evaluated in IO
+        assertFailure "must throw when given a negative number")
   where errorCalls (ErrorCall _) = Just ()
 
-main = case_negative


From git at git.haskell.org  Tue Mar 20 10:46:19 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 20 Mar 2018 10:46:19 +0000 (UTC)
Subject: [commit: ghc] branch 'wip/tdammers/D4395-new' created
Message-ID: <20180320104619.C837C3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

New branch : wip/tdammers/D4395-new
Referencing: 17531c81dcc1c822317190d4949cc8a6ab6b9c43

From git at git.haskell.org  Tue Mar 20 10:46:25 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 20 Mar 2018 10:46:25 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4395-new: This should really have been in
 the previous commit. (17531c8)
Message-ID: <20180320104625.5CAFE3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/tdammers/D4395-new
Link       : http://ghc.haskell.org/trac/ghc/changeset/17531c81dcc1c822317190d4949cc8a6ab6b9c43/ghc

>---------------------------------------------------------------

commit 17531c81dcc1c822317190d4949cc8a6ab6b9c43
Author: Richard Eisenberg <rae at cs.brynmawr.edu>
Date:   Sat Jan 27 09:55:21 2018 -0500

    This should really have been in the previous commit.


>---------------------------------------------------------------

17531c81dcc1c822317190d4949cc8a6ab6b9c43
 compiler/coreSyn/CoreOpt.hs    | 4 ++--
 compiler/simplCore/Simplify.hs | 2 +-
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/compiler/coreSyn/CoreOpt.hs b/compiler/coreSyn/CoreOpt.hs
index 0054016..e1eae8b 100644
--- a/compiler/coreSyn/CoreOpt.hs
+++ b/compiler/coreSyn/CoreOpt.hs
@@ -1000,12 +1000,12 @@ pushCoValArg co
               -- then co1 :: tyL1 ~ tyR1
               --      co2 :: tyL2 ~ tyR2
   = ASSERT2( isFunTy tyR, ppr co $$ ppr arg )
-    Just (mkSymCo co1, co2)
+    Just (mkSymCo co1, Just co2)
 
   | otherwise
   = Nothing
   where
-    (arg, res)   = splitFunTy tyR
+    (arg, _)     = splitFunTy tyR
     Pair tyL tyR = coercionKind co
 
 pushCoercionIntoLambda
diff --git a/compiler/simplCore/Simplify.hs b/compiler/simplCore/Simplify.hs
index 079fe9f..b2444e5 100644
--- a/compiler/simplCore/Simplify.hs
+++ b/compiler/simplCore/Simplify.hs
@@ -1216,7 +1216,7 @@ simplCast env body co0 cont0
         -- If the first parameter is Nothing, then simplifying revealed a
         -- reflexive coercion. Omit.
        addCoerce0 :: Maybe OutCoercion -> SimplCont -> SimplM SimplCont
-       addCoerce0 Nothing   cont = cont
+       addCoerce0 Nothing   cont = return cont
        addCoerce0 (Just co) cont = addCoerce co cont
 
        addCoerce :: OutCoercion -> SimplCont -> SimplM SimplCont


From git at git.haskell.org  Tue Mar 20 10:46:22 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 20 Mar 2018 10:46:22 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4395-new: Discard reflexive casts during
 Simplify (4faad0b)
Message-ID: <20180320104622.92A7A3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/tdammers/D4395-new
Link       : http://ghc.haskell.org/trac/ghc/changeset/4faad0bee0c8d233f939de40ce179e081b8a7c21/ghc

>---------------------------------------------------------------

commit 4faad0bee0c8d233f939de40ce179e081b8a7c21
Author: Richard Eisenberg <rae at cs.brynmawr.edu>
Date:   Fri Jan 26 22:42:46 2018 -0500

    Discard reflexive casts during Simplify
    
    Previously, we went to great lengths to build just the right
    reflexive casts, only to discard them shortly later. Now, just
    skip creating reflexive casts altogether.


>---------------------------------------------------------------

4faad0bee0c8d233f939de40ce179e081b8a7c21
 compiler/coreSyn/CoreOpt.hs    | 44 +++++++++++++++++++++++++-----------------
 compiler/simplCore/Simplify.hs | 27 +++++++++++++++++++++-----
 2 files changed, 48 insertions(+), 23 deletions(-)

diff --git a/compiler/coreSyn/CoreOpt.hs b/compiler/coreSyn/CoreOpt.hs
index 04e604e..0054016 100644
--- a/compiler/coreSyn/CoreOpt.hs
+++ b/compiler/coreSyn/CoreOpt.hs
@@ -732,9 +732,11 @@ exprIsConApp_maybe (in_scope, id_unf) expr
     go subst (Tick t expr) cont
        | not (tickishIsCode t) = go subst expr cont
     go subst (Cast expr co1) (CC args co2)
-       | Just (args', co1') <- pushCoArgs (subst_co subst co1) args
+       | Just (args', m_co1') <- pushCoArgs (subst_co subst co1) args
             -- See Note [Push coercions in exprIsConApp_maybe]
-       = go subst expr (CC args' (co1' `mkTransCo` co2))
+       = case m_co1' of
+           Just co1' -> go subst expr (CC args' (co1' `mkTransCo` co2))
+           Nothing   -> go subst expr (CC args' co2)
     go subst (App fun arg) (CC args co)
        = go subst fun (CC (subst_arg subst arg : args) co)
     go subst (Lam var body) (CC (arg:args) co)
@@ -928,36 +930,40 @@ Here we implement the "push rules" from FC papers:
   by pushing the coercion into the arguments
 -}
 
-pushCoArgs :: Coercion -> [CoreArg] -> Maybe ([CoreArg], Coercion)
-pushCoArgs co []         = return ([], co)
-pushCoArgs co (arg:args) = do { (arg',  co1) <- pushCoArg  co  arg
-                              ; (args', co2) <- pushCoArgs co1 args
-                              ; return (arg':args', co2) }
+pushCoArgs :: Coercion -> [CoreArg] -> Maybe ([CoreArg], Maybe Coercion)
+pushCoArgs co []         = return ([], Just co)
+pushCoArgs co (arg:args) = do { (arg',  m_co1) <- pushCoArg  co  arg
+                              ; case m_co1 of
+                                  Just co1 -> do { (args', m_co2) <- pushCoArgs co1 args
+                                                 ; return (arg':args', m_co2) }
+                                  Nothing  -> return (arg':args, Nothing) }
 
-pushCoArg :: Coercion -> CoreArg -> Maybe (CoreArg, Coercion)
+pushCoArg :: Coercion -> CoreArg -> Maybe (CoreArg, Maybe Coercion)
 -- We have (fun |> co) arg, and we want to transform it to
 --         (fun arg) |> co
 -- This may fail, e.g. if (fun :: N) where N is a newtype
 -- C.f. simplCast in Simplify.hs
 -- 'co' is always Representational
+-- If the returned coercion is Nothing, then it would have been reflexive
+pushCoArg co (Type ty) = do { (ty', m_co') <- pushCoTyArg co ty
+                            ; return (Type ty', m_co') }
+pushCoArg co val_arg   = do { (arg_co, m_co') <- pushCoValArg co
+                            ; return (val_arg `mkCast` arg_co, m_co') }
 
-pushCoArg co (Type ty) = do { (ty', co') <- pushCoTyArg co ty
-                            ; return (Type ty', co') }
-pushCoArg co val_arg   = do { (arg_co, co') <- pushCoValArg co
-                            ; return (mkCast val_arg arg_co, co') }
-
-pushCoTyArg :: Coercion -> Type -> Maybe (Type, Coercion)
+pushCoTyArg :: CoercionR -> Type -> Maybe (Type, Maybe CoercionR)
 -- We have (fun |> co) @ty
 -- Push the coercion through to return
 --         (fun @ty') |> co'
 -- 'co' is always Representational
+-- If the returned coercion is Nothing, then it would have been reflexive;
+-- it's faster not to compute it, though.
 pushCoTyArg co ty
   | tyL `eqType` tyR
-  = Just (ty, mkRepReflCo (piResultTy tyR ty))
+  = Just (ty, Nothing)
 
   | isForAllTy tyL
   = ASSERT2( isForAllTy tyR, ppr co $$ ppr ty )
-    Just (ty `mkCastTy` mkSymCo co1, co2)
+    Just (ty `mkCastTy` mkSymCo co1, Just co2)
 
   | otherwise
   = Nothing
@@ -977,14 +983,16 @@ pushCoTyArg co ty
         -- co2 :: ty1[ (ty|>co1)/a1 ] ~ ty2[ ty/a2 ]
         -- Arg of mkInstCo is always nominal, hence mkNomReflCo
 
-pushCoValArg :: Coercion -> Maybe (Coercion, Coercion)
+pushCoValArg :: Coercion -> Maybe (Coercion, Maybe Coercion)
 -- We have (fun |> co) arg
 -- Push the coercion through to return
 --         (fun (arg |> co_arg)) |> co_res
 -- 'co' is always Representational
+-- If the second returned Coercion is actually Nothing, then no cast is necessary;
+-- the returned coercion would have been reflexive.
 pushCoValArg co
   | tyL `eqType` tyR
-  = Just (mkRepReflCo arg, mkRepReflCo res)
+  = Just (mkRepReflCo arg, Nothing)
 
   | isFunTy tyL
   , (co1, co2) <- decomposeFunCo co
diff --git a/compiler/simplCore/Simplify.hs b/compiler/simplCore/Simplify.hs
index b123055..079fe9f 100644
--- a/compiler/simplCore/Simplify.hs
+++ b/compiler/simplCore/Simplify.hs
@@ -1213,23 +1213,40 @@ simplCast env body co0 cont0
         ; cont1 <- addCoerce co1 cont0
         ; simplExprF env body cont1 }
   where
+        -- If the first parameter is Nothing, then simplifying revealed a
+        -- reflexive coercion. Omit.
+       addCoerce0 :: Maybe OutCoercion -> SimplCont -> SimplM SimplCont
+       addCoerce0 Nothing   cont = cont
+       addCoerce0 (Just co) cont = addCoerce co cont
+
        addCoerce :: OutCoercion -> SimplCont -> SimplM SimplCont
+       addCoerce co cont  -- just skip reflexive casts
+         | isReflexiveCo co = {-#SCC "addCoerce-reflexive" #-}
+                              return cont
+                -- It's worth checking isReflexiveCo.
+                -- For example, in the initial form of a worker
+                -- we may find  (coerce T (coerce S (\x.e))) y
+                -- and we'd like it to simplify to e[y/x] in one round
+                -- of simplification
+
        addCoerce co1 (CastIt co2 cont)
          = addCoerce (mkTransCo co1 co2) cont
 
        addCoerce co cont@(ApplyToTy { sc_arg_ty = arg_ty, sc_cont = tail })
-         | Just (arg_ty', co') <- pushCoTyArg co arg_ty
-         = do { tail' <- addCoerce co' tail
-              ; return (cont { sc_arg_ty = arg_ty', sc_cont = tail' }) }
+         | Just (arg_ty', m_co') <- pushCoTyArg co arg_ty
+         = case m_co' of
+             Just co' -> do { tail' <- addCoerce co' tail
+                            ; return (cont { sc_arg_ty = arg_ty', sc_cont = tail' }) }
+             Nothing  -> return cont
 
        addCoerce co cont@(ApplyToVal { sc_arg = arg, sc_env = arg_se
                                 , sc_dup = dup, sc_cont = tail })
-         | Just (co1, co2) <- pushCoValArg co
+         | Just (co1, m_co2) <- pushCoValArg co
          , Pair _ new_ty <- coercionKind co1
          , not (isTypeLevPoly new_ty)  -- without this check, we get a lev-poly arg
                                        -- See Note [Levity polymorphism invariants] in CoreSyn
                                        -- test: typecheck/should_run/EtaExpandLevPoly
-         = do { tail' <- addCoerce co2 tail
+         = do { tail' <- addCoerce0 m_co2 tail
               ; if isReflCo co1
                 then return (cont { sc_cont = tail' })
                      -- Avoid simplifying if possible;


From git at git.haskell.org  Tue Mar 20 10:50:55 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 20 Mar 2018 10:50:55 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4395-new: Discard reflexive casts during
 Simplify (325fa91)
Message-ID: <20180320105055.3F32B3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/tdammers/D4395-new
Link       : http://ghc.haskell.org/trac/ghc/changeset/325fa912c6f8fbc767dd45a9a333ee50563761cf/ghc

>---------------------------------------------------------------

commit 325fa912c6f8fbc767dd45a9a333ee50563761cf
Author: Richard Eisenberg <rae at cs.brynmawr.edu>
Date:   Fri Jan 26 22:42:46 2018 -0500

    Discard reflexive casts during Simplify
    
    Previously, we went to great lengths to build just the right
    reflexive casts, only to discard them shortly later. Now, just
    skip creating reflexive casts altogether.


>---------------------------------------------------------------

325fa912c6f8fbc767dd45a9a333ee50563761cf
 compiler/coreSyn/CoreOpt.hs    | 48 ++++++++++++++++++++++++------------------
 compiler/simplCore/Simplify.hs | 27 +++++++++++++++++++-----
 2 files changed, 50 insertions(+), 25 deletions(-)

diff --git a/compiler/coreSyn/CoreOpt.hs b/compiler/coreSyn/CoreOpt.hs
index 04e604e..e1eae8b 100644
--- a/compiler/coreSyn/CoreOpt.hs
+++ b/compiler/coreSyn/CoreOpt.hs
@@ -732,9 +732,11 @@ exprIsConApp_maybe (in_scope, id_unf) expr
     go subst (Tick t expr) cont
        | not (tickishIsCode t) = go subst expr cont
     go subst (Cast expr co1) (CC args co2)
-       | Just (args', co1') <- pushCoArgs (subst_co subst co1) args
+       | Just (args', m_co1') <- pushCoArgs (subst_co subst co1) args
             -- See Note [Push coercions in exprIsConApp_maybe]
-       = go subst expr (CC args' (co1' `mkTransCo` co2))
+       = case m_co1' of
+           Just co1' -> go subst expr (CC args' (co1' `mkTransCo` co2))
+           Nothing   -> go subst expr (CC args' co2)
     go subst (App fun arg) (CC args co)
        = go subst fun (CC (subst_arg subst arg : args) co)
     go subst (Lam var body) (CC (arg:args) co)
@@ -928,36 +930,40 @@ Here we implement the "push rules" from FC papers:
   by pushing the coercion into the arguments
 -}
 
-pushCoArgs :: Coercion -> [CoreArg] -> Maybe ([CoreArg], Coercion)
-pushCoArgs co []         = return ([], co)
-pushCoArgs co (arg:args) = do { (arg',  co1) <- pushCoArg  co  arg
-                              ; (args', co2) <- pushCoArgs co1 args
-                              ; return (arg':args', co2) }
+pushCoArgs :: Coercion -> [CoreArg] -> Maybe ([CoreArg], Maybe Coercion)
+pushCoArgs co []         = return ([], Just co)
+pushCoArgs co (arg:args) = do { (arg',  m_co1) <- pushCoArg  co  arg
+                              ; case m_co1 of
+                                  Just co1 -> do { (args', m_co2) <- pushCoArgs co1 args
+                                                 ; return (arg':args', m_co2) }
+                                  Nothing  -> return (arg':args, Nothing) }
 
-pushCoArg :: Coercion -> CoreArg -> Maybe (CoreArg, Coercion)
+pushCoArg :: Coercion -> CoreArg -> Maybe (CoreArg, Maybe Coercion)
 -- We have (fun |> co) arg, and we want to transform it to
 --         (fun arg) |> co
 -- This may fail, e.g. if (fun :: N) where N is a newtype
 -- C.f. simplCast in Simplify.hs
 -- 'co' is always Representational
+-- If the returned coercion is Nothing, then it would have been reflexive
+pushCoArg co (Type ty) = do { (ty', m_co') <- pushCoTyArg co ty
+                            ; return (Type ty', m_co') }
+pushCoArg co val_arg   = do { (arg_co, m_co') <- pushCoValArg co
+                            ; return (val_arg `mkCast` arg_co, m_co') }
 
-pushCoArg co (Type ty) = do { (ty', co') <- pushCoTyArg co ty
-                            ; return (Type ty', co') }
-pushCoArg co val_arg   = do { (arg_co, co') <- pushCoValArg co
-                            ; return (mkCast val_arg arg_co, co') }
-
-pushCoTyArg :: Coercion -> Type -> Maybe (Type, Coercion)
+pushCoTyArg :: CoercionR -> Type -> Maybe (Type, Maybe CoercionR)
 -- We have (fun |> co) @ty
 -- Push the coercion through to return
 --         (fun @ty') |> co'
 -- 'co' is always Representational
+-- If the returned coercion is Nothing, then it would have been reflexive;
+-- it's faster not to compute it, though.
 pushCoTyArg co ty
   | tyL `eqType` tyR
-  = Just (ty, mkRepReflCo (piResultTy tyR ty))
+  = Just (ty, Nothing)
 
   | isForAllTy tyL
   = ASSERT2( isForAllTy tyR, ppr co $$ ppr ty )
-    Just (ty `mkCastTy` mkSymCo co1, co2)
+    Just (ty `mkCastTy` mkSymCo co1, Just co2)
 
   | otherwise
   = Nothing
@@ -977,14 +983,16 @@ pushCoTyArg co ty
         -- co2 :: ty1[ (ty|>co1)/a1 ] ~ ty2[ ty/a2 ]
         -- Arg of mkInstCo is always nominal, hence mkNomReflCo
 
-pushCoValArg :: Coercion -> Maybe (Coercion, Coercion)
+pushCoValArg :: Coercion -> Maybe (Coercion, Maybe Coercion)
 -- We have (fun |> co) arg
 -- Push the coercion through to return
 --         (fun (arg |> co_arg)) |> co_res
 -- 'co' is always Representational
+-- If the second returned Coercion is actually Nothing, then no cast is necessary;
+-- the returned coercion would have been reflexive.
 pushCoValArg co
   | tyL `eqType` tyR
-  = Just (mkRepReflCo arg, mkRepReflCo res)
+  = Just (mkRepReflCo arg, Nothing)
 
   | isFunTy tyL
   , (co1, co2) <- decomposeFunCo co
@@ -992,12 +1000,12 @@ pushCoValArg co
               -- then co1 :: tyL1 ~ tyR1
               --      co2 :: tyL2 ~ tyR2
   = ASSERT2( isFunTy tyR, ppr co $$ ppr arg )
-    Just (mkSymCo co1, co2)
+    Just (mkSymCo co1, Just co2)
 
   | otherwise
   = Nothing
   where
-    (arg, res)   = splitFunTy tyR
+    (arg, _)     = splitFunTy tyR
     Pair tyL tyR = coercionKind co
 
 pushCoercionIntoLambda
diff --git a/compiler/simplCore/Simplify.hs b/compiler/simplCore/Simplify.hs
index b123055..b2444e5 100644
--- a/compiler/simplCore/Simplify.hs
+++ b/compiler/simplCore/Simplify.hs
@@ -1213,23 +1213,40 @@ simplCast env body co0 cont0
         ; cont1 <- addCoerce co1 cont0
         ; simplExprF env body cont1 }
   where
+        -- If the first parameter is Nothing, then simplifying revealed a
+        -- reflexive coercion. Omit.
+       addCoerce0 :: Maybe OutCoercion -> SimplCont -> SimplM SimplCont
+       addCoerce0 Nothing   cont = return cont
+       addCoerce0 (Just co) cont = addCoerce co cont
+
        addCoerce :: OutCoercion -> SimplCont -> SimplM SimplCont
+       addCoerce co cont  -- just skip reflexive casts
+         | isReflexiveCo co = {-#SCC "addCoerce-reflexive" #-}
+                              return cont
+                -- It's worth checking isReflexiveCo.
+                -- For example, in the initial form of a worker
+                -- we may find  (coerce T (coerce S (\x.e))) y
+                -- and we'd like it to simplify to e[y/x] in one round
+                -- of simplification
+
        addCoerce co1 (CastIt co2 cont)
          = addCoerce (mkTransCo co1 co2) cont
 
        addCoerce co cont@(ApplyToTy { sc_arg_ty = arg_ty, sc_cont = tail })
-         | Just (arg_ty', co') <- pushCoTyArg co arg_ty
-         = do { tail' <- addCoerce co' tail
-              ; return (cont { sc_arg_ty = arg_ty', sc_cont = tail' }) }
+         | Just (arg_ty', m_co') <- pushCoTyArg co arg_ty
+         = case m_co' of
+             Just co' -> do { tail' <- addCoerce co' tail
+                            ; return (cont { sc_arg_ty = arg_ty', sc_cont = tail' }) }
+             Nothing  -> return cont
 
        addCoerce co cont@(ApplyToVal { sc_arg = arg, sc_env = arg_se
                                 , sc_dup = dup, sc_cont = tail })
-         | Just (co1, co2) <- pushCoValArg co
+         | Just (co1, m_co2) <- pushCoValArg co
          , Pair _ new_ty <- coercionKind co1
          , not (isTypeLevPoly new_ty)  -- without this check, we get a lev-poly arg
                                        -- See Note [Levity polymorphism invariants] in CoreSyn
                                        -- test: typecheck/should_run/EtaExpandLevPoly
-         = do { tail' <- addCoerce co2 tail
+         = do { tail' <- addCoerce0 m_co2 tail
               ; if isReflCo co1
                 then return (cont { sc_cont = tail' })
                      -- Avoid simplifying if possible;


From git at git.haskell.org  Tue Mar 20 11:53:33 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 20 Mar 2018 11:53:33 +0000 (UTC)
Subject: [commit: ghc] branch 'wip/tdammers/D4394' created
Message-ID: <20180320115333.A67943A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

New branch : wip/tdammers/D4394
Referencing: 9426a60c002c6c4d732e4a86cd94c2b63e71c16a

From git at git.haskell.org  Tue Mar 20 11:53:36 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 20 Mar 2018 11:53:36 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4394: Applying patch suggested in #11735
 to improve coercionKind perf (255a6de)
Message-ID: <20180320115336.718413A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/tdammers/D4394
Link       : http://ghc.haskell.org/trac/ghc/changeset/255a6deb77bc5794737f022301c2b16214b0f3d5/ghc

>---------------------------------------------------------------

commit 255a6deb77bc5794737f022301c2b16214b0f3d5
Author: Tobias Dammers <tdammers at gmail.com>
Date:   Wed Jan 24 16:05:55 2018 +0100

    Applying patch suggested in #11735 to improve coercionKind perf


>---------------------------------------------------------------

255a6deb77bc5794737f022301c2b16214b0f3d5
 compiler/types/Coercion.hs | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/compiler/types/Coercion.hs b/compiler/types/Coercion.hs
index 7a7918c..f559a3a 100644
--- a/compiler/types/Coercion.hs
+++ b/compiler/types/Coercion.hs
@@ -1784,6 +1784,8 @@ substitute for them all at once.  Remarkably, for Trac #11735 this single
 change reduces /total/ compile time by a factor of more than ten.
 
 -}
+=======
+>>>>>>> Applying patch suggested in #11735 to improve coercionKind perf
 
 -- | Apply 'coercionKind' to multiple 'Coercion's
 coercionKinds :: [Coercion] -> Pair [Type]


From git at git.haskell.org  Tue Mar 20 11:53:39 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 20 Mar 2018 11:53:39 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4394: Refactored coercionKindsRole (as
 per #11735) (33bef97)
Message-ID: <20180320115339.388E83A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/tdammers/D4394
Link       : http://ghc.haskell.org/trac/ghc/changeset/33bef97dcbb03db29d1aca4886dfe59dd2a89ec0/ghc

>---------------------------------------------------------------

commit 33bef97dcbb03db29d1aca4886dfe59dd2a89ec0
Author: Tobias Dammers <tdammers at gmail.com>
Date:   Wed Jan 24 17:20:20 2018 +0100

    Refactored coercionKindsRole (as per #11735)


>---------------------------------------------------------------

33bef97dcbb03db29d1aca4886dfe59dd2a89ec0
 compiler/types/Coercion.hs | 74 ++++++++++++++++------------------------------
 1 file changed, 25 insertions(+), 49 deletions(-)

diff --git a/compiler/types/Coercion.hs b/compiler/types/Coercion.hs
index f559a3a..5c9da1b 100644
--- a/compiler/types/Coercion.hs
+++ b/compiler/types/Coercion.hs
@@ -1794,77 +1794,53 @@ coercionKinds tys = sequenceA $ map coercionKind tys
 -- | Get a coercion's kind and role.
 -- Why both at once?  See Note [Computing a coercion kind and role]
 coercionKindRole :: Coercion -> (Pair Type, Role)
-coercionKindRole = go
+coercionKindRole co = (coercionKind co, coercionRole co)
+
+-- | Retrieve the role from a coercion.
+coercionRole :: Coercion -> Role
+coercionRole = go
   where
-    go (Refl r ty) = (Pair ty ty, r)
-    go (TyConAppCo r tc cos)
-      = (mkTyConApp tc <$> (sequenceA $ map coercionKind cos), r)
-    go (AppCo co1 co2)
-      = let (tys1, r1) = go co1 in
-        (mkAppTy <$> tys1 <*> coercionKind co2, r1)
-    go (ForAllCo tv1 k_co co)
-      = let Pair _ k2          = coercionKind k_co
-            tv2                = setTyVarKind tv1 k2
-            (Pair ty1 ty2, r)  = go co
-            subst = zipTvSubst [tv1] [TyVarTy tv2 `mkCastTy` mkSymCo k_co]
-            ty2' = substTyAddInScope subst ty2 in
-            -- We need free vars of ty2 in scope to satisfy the invariant
-            -- from Note [The substitution invariant]
-            -- This is doing repeated substitutions and probably doesn't
-            -- need to, see #11735
-        (mkInvForAllTy <$> Pair tv1 tv2 <*> Pair ty1 ty2', r)
-    go (FunCo r co1 co2)
-      = (mkFunTy <$> coercionKind co1 <*> coercionKind co2, r)
+    go (Refl r _) = r
+    go (TyConAppCo r _ _) = r
+    go (AppCo co1 _) = go co1
+    go (ForAllCo _ _ co) = go co
+    go (FunCo r _ _) = r
     go (CoVarCo cv) = go_var cv
     go (HoleCo h)   = go_var (coHoleCoVar h)
-    go co@(AxiomInstCo ax _ _) = (coercionKind co, coAxiomRole ax)
-    go (UnivCo _ r ty1 ty2)  = (Pair ty1 ty2, r)
-    go (SymCo co) = first swap $ go co
-    go (TransCo co1 co2)
-      = let (tys1, r) = go co1 in
-        (Pair (pFst tys1) (pSnd $ coercionKind co2), r)
+    go (AxiomInstCo ax _ _) = coAxiomRole ax
+    go (UnivCo _ r _ _)  = r
+    go (SymCo co) = go co
+    go (TransCo co1 co2) = go co1
     go (NthCo d co)
       | Just (tv1, _) <- splitForAllTy_maybe ty1
       = ASSERT( d == 0 )
-        let (tv2, _) = splitForAllTy ty2 in
-        (tyVarKind <$> Pair tv1 tv2, Nominal)
+        Nominal
 
       | otherwise
       = let (tc1,  args1) = splitTyConApp ty1
             (_tc2, args2) = splitTyConApp ty2
         in
         ASSERT2( tc1 == _tc2, ppr d $$ ppr tc1 $$ ppr _tc2 )
-        ((`getNth` d) <$> Pair args1 args2, nthRole r tc1 d)
+        (nthRole r tc1 d)
 
       where
-        (Pair ty1 ty2, r) = go co
-    go co@(LRCo {}) = (coercionKind co, Nominal)
+        (Pair ty1 ty2, r) = coercionKindRole co
+    go (LRCo {}) = Nominal
     go (InstCo co arg) = go_app co [arg]
-    go (CoherenceCo co1 co2)
-      = let (Pair t1 t2, r) = go co1 in
-        (Pair (t1 `mkCastTy` co2) t2, r)
-    go co@(KindCo {}) = (coercionKind co, Nominal)
-    go (SubCo co) = (coercionKind co, Representational)
-    go co@(AxiomRuleCo ax _) = (coercionKind co, coaxrRole ax)
+    go (CoherenceCo co1 _) = go co1
+    go (KindCo {}) = Nominal
+    go (SubCo _) = Representational
+    go (AxiomRuleCo ax _) = coaxrRole ax
 
     -------------
-    go_var cv = (coVarTypes cv, coVarRole cv)
+    go_var = coVarRole
 
     -------------
-    go_app :: Coercion -> [Coercion] -> (Pair Type, Role)
+    go_app :: Coercion -> [Coercion] -> Role
     -- Collect up all the arguments and apply all at once
     -- See Note [Nested InstCos]
     go_app (InstCo co arg) args = go_app co (arg:args)
-    go_app co              args
-      = let (pair, r) = go co in
-        (piResultTys <$> pair <*> (sequenceA $ map coercionKind args), r)
-
--- | Retrieve the role from a coercion.
-coercionRole :: Coercion -> Role
-coercionRole = snd . coercionKindRole
-  -- There's not a better way to do this, because NthCo needs the *kind*
-  -- and role of its argument. Luckily, laziness should generally avoid
-  -- the need for computing kinds in other cases.
+    go_app co              args = go co
 
 {-
 Note [Nested InstCos]


From git at git.haskell.org  Tue Mar 20 11:53:41 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 20 Mar 2018 11:53:41 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4394: Simplification as per #11735
 (3d56a05)
Message-ID: <20180320115342.001353A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/tdammers/D4394
Link       : http://ghc.haskell.org/trac/ghc/changeset/3d56a05115053eb24f3c07c97b38f06f6d949288/ghc

>---------------------------------------------------------------

commit 3d56a05115053eb24f3c07c97b38f06f6d949288
Author: Tobias Dammers <tdammers at gmail.com>
Date:   Thu Jan 25 11:16:30 2018 +0100

    Simplification as per #11735
    
    (https://ghc.haskell.org/trac/ghc/ticket/11735#comment:19)


>---------------------------------------------------------------

3d56a05115053eb24f3c07c97b38f06f6d949288
 compiler/types/Coercion.hs | 10 ++++------
 1 file changed, 4 insertions(+), 6 deletions(-)

diff --git a/compiler/types/Coercion.hs b/compiler/types/Coercion.hs
index 5c9da1b..56341d0 100644
--- a/compiler/types/Coercion.hs
+++ b/compiler/types/Coercion.hs
@@ -1826,7 +1826,7 @@ coercionRole = go
       where
         (Pair ty1 ty2, r) = coercionKindRole co
     go (LRCo {}) = Nominal
-    go (InstCo co arg) = go_app co [arg]
+    go (InstCo co arg) = go_app co
     go (CoherenceCo co1 _) = go co1
     go (KindCo {}) = Nominal
     go (SubCo _) = Representational
@@ -1836,11 +1836,9 @@ coercionRole = go
     go_var = coVarRole
 
     -------------
-    go_app :: Coercion -> [Coercion] -> Role
-    -- Collect up all the arguments and apply all at once
-    -- See Note [Nested InstCos]
-    go_app (InstCo co arg) args = go_app co (arg:args)
-    go_app co              args = go co
+    go_app :: Coercion -> Role
+    go_app (InstCo co arg) = go_app co
+    go_app co              = go co
 
 {-
 Note [Nested InstCos]


From git at git.haskell.org  Tue Mar 20 11:53:44 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 20 Mar 2018 11:53:44 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4394: Added SCCs to hunt down #14683
 (91e4708)
Message-ID: <20180320115344.CAD7F3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/tdammers/D4394
Link       : http://ghc.haskell.org/trac/ghc/changeset/91e47082a5512960c0b636d788462f6f80a1a1a5/ghc

>---------------------------------------------------------------

commit 91e47082a5512960c0b636d788462f6f80a1a1a5
Author: Tobias Dammers <tdammers at gmail.com>
Date:   Wed Jan 24 16:07:00 2018 +0100

    Added SCCs to hunt down #14683


>---------------------------------------------------------------

91e47082a5512960c0b636d788462f6f80a1a1a5
 compiler/simplCore/Simplify.hs | 79 +++++++++++++++++++++++++-----------------
 compiler/types/TyCoRep.hs      |  9 ++---
 2 files changed, 53 insertions(+), 35 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc 91e47082a5512960c0b636d788462f6f80a1a1a5

From git at git.haskell.org  Tue Mar 20 11:53:50 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 20 Mar 2018 11:53:50 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4394: Another fix as per D4394 (c9212b4)
Message-ID: <20180320115350.63F0C3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/tdammers/D4394
Link       : http://ghc.haskell.org/trac/ghc/changeset/c9212b4764de580c647dc722cbfe6fd6d4b61c19/ghc

>---------------------------------------------------------------

commit c9212b4764de580c647dc722cbfe6fd6d4b61c19
Author: Tobias Dammers <tdammers at gmail.com>
Date:   Mon Mar 5 12:50:35 2018 +0100

    Another fix as per D4394


>---------------------------------------------------------------

c9212b4764de580c647dc722cbfe6fd6d4b61c19
 compiler/types/Coercion.hs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/compiler/types/Coercion.hs b/compiler/types/Coercion.hs
index dd4d055..8550e85 100644
--- a/compiler/types/Coercion.hs
+++ b/compiler/types/Coercion.hs
@@ -1295,7 +1295,7 @@ mkCoCast c g
       | tc `hasKey` heqTyConKey        = (4, Nominal)
       | tc `hasKey` coercibleTyConKey  = (3, Representational)
       | otherwise                      = pprPanic "mkCoCast" (ppr g $$ ppr (coercionKind g))
-    co_list = decomposeCo n_args g (replicate (n_args - 2) Nominal ++ repeat role)
+    co_list = decomposeCo (tyConArity tc) g (tyConRolesRepresentational tc)
     g1 = co_list `getNth` (n_args - 2)
     g2 = co_list `getNth` (n_args - 1)
 


From git at git.haskell.org  Tue Mar 20 11:53:47 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 20 Mar 2018 11:53:47 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4394: Caching coercion roles in NthCo and
 coercionKindsRole refactoring (#11735) (c8efa15)
Message-ID: <20180320115347.9A44F3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/tdammers/D4394
Link       : http://ghc.haskell.org/trac/ghc/changeset/c8efa159be470d7039d4c09405bc04c7d3499d36/ghc

>---------------------------------------------------------------

commit c8efa159be470d7039d4c09405bc04c7d3499d36
Author: Richard Eisenberg <rae at cs.brynmawr.edu>
Date:   Fri Jan 26 22:28:42 2018 -0500

    Caching coercion roles in NthCo and coercionKindsRole refactoring (#11735)
    
    Reviewers: goldfire, bgamari
    
    Subscribers: rwbarton, thomie, carter
    
    Differential Revision: https://phabricator.haskell.org/D4394


>---------------------------------------------------------------

c8efa159be470d7039d4c09405bc04c7d3499d36
 docs/core-spec/CoreLint.ott  |   5 +++--
 docs/core-spec/CoreSyn.ott   |   6 ++++--
 docs/core-spec/core-spec.mng |   2 +-
 docs/core-spec/core-spec.pdf | Bin 354307 -> 355707 bytes
 4 files changed, 8 insertions(+), 5 deletions(-)

diff --git a/docs/core-spec/CoreLint.ott b/docs/core-spec/CoreLint.ott
index 3a3468d..1fb9e09 100644
--- a/docs/core-spec/CoreLint.ott
+++ b/docs/core-spec/CoreLint.ott
@@ -299,12 +299,13 @@ G |-ty ti : k2'
 not (si is_a_coercion)
 not (ti is_a_coercion)
 R' = (tyConRolesX R T)[i]
+R' <= R0
 ---------------------- :: NthCoTyCon
-G |-co nth i g : si k2~R' k2' ti
+G |-co nth R0 i g : si k2~R0 k2' ti
 
 G |-co g : (forall z1_k1.t1) k3~R k4 (forall z2_k2.t2)
 --------------------------- :: NthCoForAll
-G |-co nth 0 g : k1 *~Nom * k2
+G |-co nth R0 0 g : k1 *~R0 * k2
 
 G |-co g : (s1 s2) k~Nom k' (t1 t2)
 G |-ty s1 : k1
diff --git a/docs/core-spec/CoreSyn.ott b/docs/core-spec/CoreSyn.ott
index 78118d5..e12f68b 100644
--- a/docs/core-spec/CoreSyn.ott
+++ b/docs/core-spec/CoreSyn.ott
@@ -152,8 +152,8 @@ g {{ tex \gamma }}, h {{ tex \eta }} :: 'Coercion_' ::= {{ com Coercions, \coder
   | g1 ; g2                 ::   :: TransCo       {{ com \ctor{TransCo}: Transitivity }}
   | mu </ ti // i /> $ </ gj // j />
                             ::   :: AxiomRuleCo   {{ com \ctor{AxiomRuleCo}: Axiom-rule application (for type-nats) }}
-  | nth I g                 ::   :: NthCo         {{ com \ctor{NthCo}: Projection (0-indexed) }}
-    {{ tex \textsf{nth}^{[[I]]}\,[[g]] }}
+  | nth R I g               ::   :: NthCo         {{ com \ctor{NthCo}: Projection (0-indexed) }}
+    {{ tex \textsf{nth}^{[[I]]}_{[[R]]}\,[[g]] }}
   | LorR g                  ::   :: LRCo          {{ com \ctor{LRCo}: Left/right projection }}
   | g @ h                   ::   :: InstCo        {{ com \ctor{InstCo}: Instantiation }}
   | g |> h                  ::   :: CoherenceCo   {{ com \ctor{CoherenceCo}: Coherence }}
@@ -453,6 +453,8 @@ formula :: 'formula_' ::=
   | role_list1 = role_list2            ::   :: eq_role_list
   | R1 /= R2                           ::   :: role_neq
   | R1 = R2                            ::   :: eq_role
+  | R1 <= R2                           ::   :: lte_role
+    {{ tex [[R1]] \leq [[R2]] }}
   | </ Ki // i /> = tyConDataCons T    ::   :: tyConDataCons
   | O ( n ) = R                        ::   :: role_lookup
   | R elt role_list                    ::   :: role_elt
diff --git a/docs/core-spec/core-spec.mng b/docs/core-spec/core-spec.mng
index 5800321..64e90bb 100644
--- a/docs/core-spec/core-spec.mng
+++ b/docs/core-spec/core-spec.mng
@@ -30,7 +30,7 @@ System FC, as implemented in GHC\footnote{This
 document was originally prepared by Richard Eisenberg (\texttt{eir at cis.upenn.edu}),
 but it should be maintained by anyone who edits the functions or data structures
 mentioned in this file. Please feel free to contact Richard for more information.}\\
-\Large 23 October, 2015
+\Large 26 January, 2018
 \end{center}
 
 \section{Introduction}
diff --git a/docs/core-spec/core-spec.pdf b/docs/core-spec/core-spec.pdf
index 1e13911..3732818 100644
Binary files a/docs/core-spec/core-spec.pdf and b/docs/core-spec/core-spec.pdf differ


From git at git.haskell.org  Tue Mar 20 11:53:53 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 20 Mar 2018 11:53:53 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4394: NthCo handling,
 assertions and documentation improvements (5a74176)
Message-ID: <20180320115353.29B7E3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/tdammers/D4394
Link       : http://ghc.haskell.org/trac/ghc/changeset/5a741763a91c46835126527630c5b5bac9370de3/ghc

>---------------------------------------------------------------

commit 5a741763a91c46835126527630c5b5bac9370de3
Author: Tobias Dammers <tdammers at gmail.com>
Date:   Sun Mar 4 21:07:13 2018 +0100

    NthCo handling, assertions and documentation improvements


>---------------------------------------------------------------

5a741763a91c46835126527630c5b5bac9370de3
 compiler/types/Coercion.hs | 160 +++++++++++++++++++++++++++------------------
 1 file changed, 95 insertions(+), 65 deletions(-)

diff --git a/compiler/types/Coercion.hs b/compiler/types/Coercion.hs
index 31db1d3..a1368de 100644
--- a/compiler/types/Coercion.hs
+++ b/compiler/types/Coercion.hs
@@ -230,7 +230,8 @@ where co_rep1, co_rep2 are the coercions on the representations.
 -- > decomposeCo 3 c [r1, r2, r3] = [nth r1 0 c, nth r2 1 c, nth r3 2 c]
 decomposeCo :: Arity -> Coercion
             -> [Role]  -- the roles of the output coercions
-                       -- this must have at least as many entries as the Arity provided
+                       -- this must have at least as many
+                       -- entries as the Arity provided
             -> [Coercion]
 decomposeCo arity co rs
   = [mkNthCo r n co | (n,r) <- [0..(arity-1)] `zip` rs ]
@@ -813,70 +814,99 @@ mkTransCo co1 co2       = TransCo co1 co2
 
 mkNthCo :: HasDebugCallStack
         => Role  -- the role of the coercion you're creating
-        -> Int -> Coercion -> Coercion
--- If the Coercion passed in is between forall-types, then the Int must
--- be 0 and the role must be Nominal. If the Coercion passed in is between
--- T tys and T tys', then the Int must be less than the length of tys/tys'
--- (which must be the same lengths). If the role of the Coercion is
--- nominal, then the role passed in must be nominal. If the role of the
--- Coercion is representational, then the role passed in must be
--- tyConRolesRepresentational T !! n. If the role of the Coercion
--- is Phantom, then the role passed in must be Phantom.
--- See also Note [NthCo Cached Roles] if you're wondering why it's
--- blaringly obvious that we should be *computing* this role instead
--- of passing it in.
-mkNthCo r 0 (Refl _ ty)
-  | Just (tv, _) <- splitForAllTy_maybe ty
-  = ASSERT( r == Nominal )
-    Refl r (tyVarKind tv)
-mkNthCo r n (Refl r0 ty)
-  = ASSERT2( ok_tc_app ty n, ppr n $$ ppr ty )
-    ASSERT( nthRole r0 tc n == r )
-    mkReflCo r (tyConAppArgN n ty)
-  where tc = tyConAppTyCon ty
-
-        ok_tc_app :: Type -> Int -> Bool
-        ok_tc_app ty n
-          | Just (_, tys) <- splitTyConApp_maybe ty
-          = tys `lengthExceeds` n
-          | isForAllTy ty  -- nth:0 pulls out a kind coercion from a hetero forall
-          = n == 0
-          | otherwise
-          = False
-
-mkNthCo r 0 (ForAllCo _ kind_co _)
-  = ASSERT( r == Nominal )
-    kind_co
-  -- If co :: (forall a1:k1. t1) ~ (forall a2:k2. t2)
-  -- then (nth 0 co :: k1 ~N k2)
-
-mkNthCo r n co@(FunCo r0 arg res)
-  -- See Note [Function coercions]
-  -- If FunCo _ arg_co res_co ::   (s1:TYPE sk1 -> s2:TYPE sk2)
-  --                             ~ (t1:TYPE tk1 -> t2:TYPE tk2)
-  -- Then we want to behave as if co was
-  --    TyConAppCo argk_co resk_co arg_co res_co
-  -- where
-  --    argk_co :: sk1 ~ tk1  =  mkNthCo 0 (mkKindCo arg_co)
-  --    resk_co :: sk2 ~ tk2  =  mkNthCo 0 (mkKindCo res_co)
-  --                             i.e. mkRuntimeRepCo
-  = case n of
-      0 -> ASSERT( r == Nominal ) mkRuntimeRepCo arg
-      1 -> ASSERT( r == Nominal ) mkRuntimeRepCo res
-      2 -> ASSERT( r == r0 )      arg
-      3 -> ASSERT( r == r0 )      res
-      _ -> pprPanic "mkNthCo(FunCo)" (ppr n $$ ppr co)
-
-mkNthCo r n (TyConAppCo r0 tc arg_cos) = ASSERT2( r == nthRole r0 tc n
-                                                , (vcat [ ppr tc
-                                                        , ppr arg_cos
-                                                        , ppr r0
-                                                        , ppr n
-                                                        , ppr r ]) )
-                                         arg_cos `getNth` n
-
-mkNthCo r n co =
-  NthCo r n co
+        -> Int
+				-> Coercion
+				-> Coercion
+mkNthCo r n co
+  = ASSERT(good_call)
+    go r n co
+  where
+		(ty1, ty2) = coercionKind co
+    good_call
+		  -- If the Coercion passed in is between forall-types, then the Int must
+		  -- be 0 and the role must be Nominal.
+      | Just (tv1, _) <- splitForAllTy_maybe ty1
+      , Just (tv2, _) <- splitForAllTy_maybe ty2
+      = n == 0 && r == Nominal
+
+      -- If the Coercion passed in is between T tys and T tys', then the Int
+      -- must be less than the length of tys/tys' (which must be the same
+      -- lengths).
+      --
+      -- If the role of the Coercion is nominal, then the role passed in must
+      -- be nominal. If the role of the Coercion is representational, then the
+      -- role passed in must be tyConRolesRepresentational T !! n. If the role
+      -- of the Coercion is Phantom, then the role passed in must be Phantom.
+      --
+      -- See also Note [NthCo Cached Roles] if you're wondering why it's
+      -- blaringly obvious that we should be *computing* this role instead of
+      -- passing it in.
+      | Just (tc1, tys1) <- splitTyConnApp_maybe ty1
+      , Just (tc2, tys1) <- splitForAllTy_maybe ty2
+      , tc1 == tc2
+      = let len1 = length tys1
+            len2 = length tys2
+            good_role = case coercionRole co of
+                          Nominal -> r == Nominal
+                          Representational -> r == (tyConRolesRepresentational tc1 !! n)
+                          Phantom -> r == Phantom
+        in len1 == len2 && n < len1 && good_role
+
+      | otherwise
+			= True
+
+    go r 0 (Refl _ ty)
+      | Just (tv, _) <- splitForAllTy_maybe ty
+      = ASSERT( r == Nominal )
+        Refl r (tyVarKind tv)
+    go r n (Refl r0 ty)
+      = ASSERT2( ok_tc_app ty n, ppr n $$ ppr ty )
+        ASSERT( nthRole r0 tc n == r )
+        mkReflCo r (tyConAppArgN n ty)
+      where tc = tyConAppTyCon ty
+
+            ok_tc_app :: Type -> Int -> Bool
+            ok_tc_app ty n
+              | Just (_, tys) <- splitTyConApp_maybe ty
+              = tys `lengthExceeds` n
+              | isForAllTy ty  -- nth:0 pulls out a kind coercion from a hetero forall
+              = n == 0
+              | otherwise
+              = False
+
+    go r 0 (ForAllCo _ kind_co _)
+      = ASSERT( r == Nominal )
+        kind_co
+      -- If co :: (forall a1:k1. t1) ~ (forall a2:k2. t2)
+      -- then (nth 0 co :: k1 ~N k2)
+
+    go r n co@(FunCo r0 arg res)
+      -- See Note [Function coercions]
+      -- If FunCo _ arg_co res_co ::   (s1:TYPE sk1 -> s2:TYPE sk2)
+      --                             ~ (t1:TYPE tk1 -> t2:TYPE tk2)
+      -- Then we want to behave as if co was
+      --    TyConAppCo argk_co resk_co arg_co res_co
+      -- where
+      --    argk_co :: sk1 ~ tk1  =  mkNthCo 0 (mkKindCo arg_co)
+      --    resk_co :: sk2 ~ tk2  =  mkNthCo 0 (mkKindCo res_co)
+      --                             i.e. mkRuntimeRepCo
+      = case n of
+          0 -> ASSERT( r == Nominal ) mkRuntimeRepCo arg
+          1 -> ASSERT( r == Nominal ) mkRuntimeRepCo res
+          2 -> ASSERT( r == r0 )      arg
+          3 -> ASSERT( r == r0 )      res
+          _ -> pprPanic "mkNthCo(FunCo)" (ppr n $$ ppr co)
+
+    go r n (TyConAppCo r0 tc arg_cos) = ASSERT2( r == nthRole r0 tc n
+                                                    , (vcat [ ppr tc
+                                                            , ppr arg_cos
+                                                            , ppr r0
+                                                            , ppr n
+                                                            , ppr r ]) )
+                                             arg_cos `getNth` n
+
+    mkNthCo r n co =
+      NthCo r n co
 
 -- | If you're about to call @mkNthCo r n co@, then @r@ should be
 -- whatever @nthCoRole n co@ returns.


From git at git.haskell.org  Tue Mar 20 11:53:58 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 20 Mar 2018 11:53:58 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4394: Documented invariant on cached
 roles (be4891f)
Message-ID: <20180320115358.AD05D3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/tdammers/D4394
Link       : http://ghc.haskell.org/trac/ghc/changeset/be4891f72a7aa345e2c50e73e50676296d7534e0/ghc

>---------------------------------------------------------------

commit be4891f72a7aa345e2c50e73e50676296d7534e0
Author: Tobias Dammers <tdammers at gmail.com>
Date:   Wed Feb 7 13:45:01 2018 +0100

    Documented invariant on cached roles


>---------------------------------------------------------------

be4891f72a7aa345e2c50e73e50676296d7534e0
 compiler/types/TyCoRep.hs | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/compiler/types/TyCoRep.hs b/compiler/types/TyCoRep.hs
index c719b31..32fdfaa 100644
--- a/compiler/types/TyCoRep.hs
+++ b/compiler/types/TyCoRep.hs
@@ -833,7 +833,11 @@ data Coercion
     -- :: "e" _ -> e0 -> e (inverse of TyConAppCo, see Note [TyConAppCo roles])
     -- Using NthCo on a ForAllCo gives an N coercion always
     -- See Note [NthCo and newtypes]
+    --
+    -- Invariant:  (NthCo r i co), it is always the case that r = role of (Nth i co)
+    -- That is: the role of the entire coercion is redundantly cached here.
     -- See Note [NthCo Cached Roles]
+    --
     -- The Role might be more permissive than otherwise possible. That is, even
     -- if the Coercion inside is Nominal, the role could be Representational
     -- (it's like using a SubCo)


From git at git.haskell.org  Tue Mar 20 11:53:55 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 20 Mar 2018 11:53:55 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4394: Fixed NthCo Note (discussion in
 D4385) (1d74d1e)
Message-ID: <20180320115355.E67B53A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/tdammers/D4394
Link       : http://ghc.haskell.org/trac/ghc/changeset/1d74d1ec1be42850b83eca800b80189ab868aa00/ghc

>---------------------------------------------------------------

commit 1d74d1ec1be42850b83eca800b80189ab868aa00
Author: Tobias Dammers <tdammers at gmail.com>
Date:   Wed Feb 7 13:19:33 2018 +0100

    Fixed NthCo Note (discussion in D4385)
    
    https://phabricator.haskell.org/D4385#inline-34161


>---------------------------------------------------------------

1d74d1ec1be42850b83eca800b80189ab868aa00
 compiler/types/TyCoRep.hs | 22 ++++++++++++++--------
 1 file changed, 14 insertions(+), 8 deletions(-)

diff --git a/compiler/types/TyCoRep.hs b/compiler/types/TyCoRep.hs
index 014dadc..c719b31 100644
--- a/compiler/types/TyCoRep.hs
+++ b/compiler/types/TyCoRep.hs
@@ -1157,14 +1157,20 @@ in the "Safe Coercions" paper (ICFP '14).
 
 Note [NthCo Cached Roles]
 ~~~~~~~~~~~~~~~~~~~~~~~~~
-Looking at coercionKind and coercionRole, we see that in order to find the Role
-for an NthCo, we have to know the kind; unfortunately, calculating the coercion
-kind for a nested NthCo is quadratic in the nesting depth, so we would like to
-avoid doing that as much as possible. To this end, we calculate the Role at
-construction time, and store it in the NthCo itself, thus removing the need to
-do the calculation on the fly.
-
-See Trac #11735 for the discussion that led to this.
+Why do we cache the role of NthCo in the NthCo constructor?
+Because computing role(Nth i co) involves figuring out that
+
+  co :: T tys1 ~ T tys2
+
+using coercionKind, and finding (coercionRole co), and then looking
+at the tyConRoles of T. Avoiding bad asymptotic behaviour here means
+we have to compute the kind and role of a coercion simultaneously,
+which makes the code complicated and inefficient.
+
+This only happens for NthCo. Caching the role solves the problem, and
+allows coercionKind and coercionRole to be simple.
+
+See Trac #11735
 
 Note [InstCo roles]
 ~~~~~~~~~~~~~~~~~~~


From git at git.haskell.org  Tue Mar 20 11:54:01 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 20 Mar 2018 11:54:01 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4394: Caching coercion roles in NthCo
 (#11735) (7661e48)
Message-ID: <20180320115401.8ACC93A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/tdammers/D4394
Link       : http://ghc.haskell.org/trac/ghc/changeset/7661e48d3a57fc1b551d82ac3ecf3043ca864dd4/ghc

>---------------------------------------------------------------

commit 7661e48d3a57fc1b551d82ac3ecf3043ca864dd4
Author: Tobias Dammers <tdammers at gmail.com>
Date:   Thu Jan 25 20:33:58 2018 +0100

    Caching coercion roles in NthCo (#11735)


>---------------------------------------------------------------

7661e48d3a57fc1b551d82ac3ecf3043ca864dd4
 compiler/coreSyn/CoreFVs.hs      |  2 +-
 compiler/coreSyn/CoreLint.hs     |  2 +-
 compiler/iface/TcIface.hs        |  2 +-
 compiler/iface/ToIface.hs        |  2 +-
 compiler/typecheck/TcTyDecls.hs  |  2 +-
 compiler/typecheck/TcType.hs     |  2 +-
 compiler/typecheck/TcUnify.hs    |  2 +-
 compiler/typecheck/TcValidity.hs |  2 +-
 compiler/types/Coercion.hs       | 45 ++++++++++++++++++++++------------------
 compiler/types/FamInstEnv.hs     |  2 +-
 compiler/types/OptCoercion.hs    |  4 ++--
 compiler/types/TyCoRep.hs        | 36 +++++++++++++++++++++++++-------
 compiler/types/Type.hs           |  8 +++----
 13 files changed, 68 insertions(+), 43 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc 7661e48d3a57fc1b551d82ac3ecf3043ca864dd4

From git at git.haskell.org  Tue Mar 20 11:54:04 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 20 Mar 2018 11:54:04 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4394: Fixed unused variables (27bf889)
Message-ID: <20180320115404.543F63A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/tdammers/D4394
Link       : http://ghc.haskell.org/trac/ghc/changeset/27bf8896d805ccbbbc7b45434a95873fc7e637ac/ghc

>---------------------------------------------------------------

commit 27bf8896d805ccbbbc7b45434a95873fc7e637ac
Author: Tobias Dammers <tdammers at gmail.com>
Date:   Mon Mar 5 15:18:41 2018 +0100

    Fixed unused variables


>---------------------------------------------------------------

27bf8896d805ccbbbc7b45434a95873fc7e637ac
 compiler/types/Coercion.hs | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/compiler/types/Coercion.hs b/compiler/types/Coercion.hs
index 8550e85..1e529f7 100644
--- a/compiler/types/Coercion.hs
+++ b/compiler/types/Coercion.hs
@@ -826,8 +826,8 @@ mkNthCo r n co
     good_call
       -- If the Coercion passed in is between forall-types, then the Int must
       -- be 0 and the role must be Nominal.
-      | Just (tv1, _) <- splitForAllTy_maybe ty1
-      , Just (tv2, _) <- splitForAllTy_maybe ty2
+      | Just (_tv1, _) <- splitForAllTy_maybe ty1
+      , Just (_tv2, _) <- splitForAllTy_maybe ty2
       = n == 0 && r == Nominal
 
       -- If the Coercion passed in is between T tys and T tys', then the Int
@@ -1288,12 +1288,12 @@ mkCoCast c g
        -- g1 :: s1 ~# s2
        -- g2 :: t1 ~# t2
     (tc, _) = splitTyConApp (pFst $ coercionKind g)
-    (n_args, role)
-      | tc `hasKey` eqPrimTyConKey     = (4, Nominal)
-      | tc `hasKey` eqReprPrimTyConKey = (4, Representational)
-      | tc `hasKey` eqTyConKey         = (3, Nominal)
-      | tc `hasKey` heqTyConKey        = (4, Nominal)
-      | tc `hasKey` coercibleTyConKey  = (3, Representational)
+    n_args
+      | tc `hasKey` eqPrimTyConKey     = 4
+      | tc `hasKey` eqReprPrimTyConKey = 4
+      | tc `hasKey` eqTyConKey         = 3
+      | tc `hasKey` heqTyConKey        = 4
+      | tc `hasKey` coercibleTyConKey  = 3
       | otherwise                      = pprPanic "mkCoCast" (ppr g $$ ppr (coercionKind g))
     co_list = decomposeCo (tyConArity tc) g (tyConRolesRepresentational tc)
     g1 = co_list `getNth` (n_args - 2)


From git at git.haskell.org  Tue Mar 20 11:54:07 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 20 Mar 2018 11:54:07 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4394: Removed dead code (ac2d7b6)
Message-ID: <20180320115407.19CF43A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/tdammers/D4394
Link       : http://ghc.haskell.org/trac/ghc/changeset/ac2d7b60aca2b1d986bc11cde858ef0346a2d3fc/ghc

>---------------------------------------------------------------

commit ac2d7b60aca2b1d986bc11cde858ef0346a2d3fc
Author: Tobias Dammers <tdammers at gmail.com>
Date:   Mon Mar 5 12:09:17 2018 +0100

    Removed dead code


>---------------------------------------------------------------

ac2d7b60aca2b1d986bc11cde858ef0346a2d3fc
 compiler/types/Coercion.hs | 7 +------
 1 file changed, 1 insertion(+), 6 deletions(-)

diff --git a/compiler/types/Coercion.hs b/compiler/types/Coercion.hs
index af3cb2c..fbb8de9 100644
--- a/compiler/types/Coercion.hs
+++ b/compiler/types/Coercion.hs
@@ -13,7 +13,7 @@ module Coercion (
         Coercion, CoercionN, CoercionR, CoercionP,
         UnivCoProvenance, CoercionHole, LeftOrRight(..),
         Var, CoVar, TyCoVar,
-        Role(..), ltRole, lteRole,
+        Role(..), ltRole,
 
         -- ** Functions over coercions
         coVarTypes, coVarKind, coVarKindsTypesRole, coVarRole,
@@ -1129,11 +1129,6 @@ ltRole Representational _       = False
 ltRole Nominal          Nominal = False
 ltRole Nominal          _       = True
 
-lteRole :: Role -> Role -> Bool
--- Is one role <= the other?
--- Nominal < Representational < Phantom
-lteRole r1 r2 = r1 == r2 || r1 `ltRole` r2
-
 -------------------------------
 
 -- | like mkKindCo, but aggressively & recursively optimizes to avoid using


From git at git.haskell.org  Tue Mar 20 11:54:18 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 20 Mar 2018 11:54:18 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4394: Tighten cached role in NthCo
 (9d30c1c)
Message-ID: <20180320115418.4CAB43A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/tdammers/D4394
Link       : http://ghc.haskell.org/trac/ghc/changeset/9d30c1c8d9b5bd4013d13bbb9e241b68e4530aa7/ghc

>---------------------------------------------------------------

commit 9d30c1c8d9b5bd4013d13bbb9e241b68e4530aa7
Author: Richard Eisenberg <rae at cs.brynmawr.edu>
Date:   Mon Feb 12 13:02:23 2018 -0500

    Tighten cached role in NthCo


>---------------------------------------------------------------

9d30c1c8d9b5bd4013d13bbb9e241b68e4530aa7
 compiler/coreSyn/CoreLint.hs     |   9 +--
 compiler/coreSyn/CoreUtils.hs    |   2 +-
 compiler/iface/TcIface.hs        |   3 +-
 compiler/iface/ToIface.hs        |   2 +-
 compiler/typecheck/TcEvidence.hs |   3 +-
 compiler/types/Coercion.hs       | 168 ++++++++++++++++++++++-----------------
 compiler/types/Coercion.hs-boot  |   2 +-
 compiler/types/OptCoercion.hs    |  20 ++---
 compiler/types/TyCoRep.hs        |   6 +-
 docs/core-spec/CoreLint.ott      |   5 +-
 10 files changed, 115 insertions(+), 105 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc 9d30c1c8d9b5bd4013d13bbb9e241b68e4530aa7

From git at git.haskell.org  Tue Mar 20 11:54:12 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 20 Mar 2018 11:54:12 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4394: Fixes to Coercion.hs (45d841e)
Message-ID: <20180320115412.AEBEB3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/tdammers/D4394
Link       : http://ghc.haskell.org/trac/ghc/changeset/45d841eef492139d915ef8691be471f2f8556d42/ghc

>---------------------------------------------------------------

commit 45d841eef492139d915ef8691be471f2f8556d42
Author: Tobias Dammers <tdammers at gmail.com>
Date:   Mon Mar 5 11:20:34 2018 +0100

    Fixes to Coercion.hs


>---------------------------------------------------------------

45d841eef492139d915ef8691be471f2f8556d42
 compiler/types/Coercion.hs | 19 ++++++++++---------
 1 file changed, 10 insertions(+), 9 deletions(-)

diff --git a/compiler/types/Coercion.hs b/compiler/types/Coercion.hs
index a1368de..af3cb2c 100644
--- a/compiler/types/Coercion.hs
+++ b/compiler/types/Coercion.hs
@@ -815,16 +815,17 @@ mkTransCo co1 co2       = TransCo co1 co2
 mkNthCo :: HasDebugCallStack
         => Role  -- the role of the coercion you're creating
         -> Int
-				-> Coercion
-				-> Coercion
+        -> Coercion
+        -> Coercion
 mkNthCo r n co
   = ASSERT(good_call)
     go r n co
   where
-		(ty1, ty2) = coercionKind co
+    Pair ty1 ty2 = coercionKind co
+
     good_call
-		  -- If the Coercion passed in is between forall-types, then the Int must
-		  -- be 0 and the role must be Nominal.
+      -- If the Coercion passed in is between forall-types, then the Int must
+      -- be 0 and the role must be Nominal.
       | Just (tv1, _) <- splitForAllTy_maybe ty1
       , Just (tv2, _) <- splitForAllTy_maybe ty2
       = n == 0 && r == Nominal
@@ -841,8 +842,8 @@ mkNthCo r n co
       -- See also Note [NthCo Cached Roles] if you're wondering why it's
       -- blaringly obvious that we should be *computing* this role instead of
       -- passing it in.
-      | Just (tc1, tys1) <- splitTyConnApp_maybe ty1
-      , Just (tc2, tys1) <- splitForAllTy_maybe ty2
+      | Just (tc1, tys1) <- splitTyConApp_maybe ty1
+      , Just (tc2, tys2) <- splitTyConApp_maybe ty2
       , tc1 == tc2
       = let len1 = length tys1
             len2 = length tys2
@@ -853,7 +854,7 @@ mkNthCo r n co
         in len1 == len2 && n < len1 && good_role
 
       | otherwise
-			= True
+      = True
 
     go r 0 (Refl _ ty)
       | Just (tv, _) <- splitForAllTy_maybe ty
@@ -905,7 +906,7 @@ mkNthCo r n co
                                                             , ppr r ]) )
                                              arg_cos `getNth` n
 
-    mkNthCo r n co =
+    go r n co =
       NthCo r n co
 
 -- | If you're about to call @mkNthCo r n co@, then @r@ should be


From git at git.haskell.org  Tue Mar 20 11:54:15 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 20 Mar 2018 11:54:15 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4394: Refactor mkCoCast (78fa305)
Message-ID: <20180320115415.770803A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/tdammers/D4394
Link       : http://ghc.haskell.org/trac/ghc/changeset/78fa305c7c0808fb079c7f82765cf1c1b250b8db/ghc

>---------------------------------------------------------------

commit 78fa305c7c0808fb079c7f82765cf1c1b250b8db
Author: Tobias Dammers <tdammers at gmail.com>
Date:   Tue Mar 6 12:09:56 2018 +0100

    Refactor mkCoCast
    
    Get rid of ugly case pattern matching in favor of simply getting the
    last two arguments unconditionally.


>---------------------------------------------------------------

78fa305c7c0808fb079c7f82765cf1c1b250b8db
 compiler/types/Coercion.hs | 19 +++++++------------
 1 file changed, 7 insertions(+), 12 deletions(-)

diff --git a/compiler/types/Coercion.hs b/compiler/types/Coercion.hs
index 1e529f7..33e3802 100644
--- a/compiler/types/Coercion.hs
+++ b/compiler/types/Coercion.hs
@@ -1282,22 +1282,17 @@ mkPiCo r v co | isTyVar v = mkHomoForAllCos [v] co
 -- itself always representational.
 mkCoCast :: Coercion -> CoercionR -> Coercion
 mkCoCast c g
+  | (g2:g1:_) <- reverse co_list
   = mkSymCo g1 `mkTransCo` c `mkTransCo` g2
+
+  | otherwise
+  = pprPanic "mkCoCast" (ppr g $$ ppr (coercionKind g))
   where
-       -- g  :: (s1 ~# t1) ~# (s2 ~# t2)
-       -- g1 :: s1 ~# s2
-       -- g2 :: t1 ~# t2
+    -- g  :: (s1 ~# t1) ~# (s2 ~# t2)
+    -- g1 :: s1 ~# s2
+    -- g2 :: t1 ~# t2
     (tc, _) = splitTyConApp (pFst $ coercionKind g)
-    n_args
-      | tc `hasKey` eqPrimTyConKey     = 4
-      | tc `hasKey` eqReprPrimTyConKey = 4
-      | tc `hasKey` eqTyConKey         = 3
-      | tc `hasKey` heqTyConKey        = 4
-      | tc `hasKey` coercibleTyConKey  = 3
-      | otherwise                      = pprPanic "mkCoCast" (ppr g $$ ppr (coercionKind g))
     co_list = decomposeCo (tyConArity tc) g (tyConRolesRepresentational tc)
-    g1 = co_list `getNth` (n_args - 2)
-    g2 = co_list `getNth` (n_args - 1)
 
 {-
 %************************************************************************


From git at git.haskell.org  Tue Mar 20 11:54:09 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 20 Mar 2018 11:54:09 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4394: Make mkNthCo take a Role parameter.
 (a3bdf13)
Message-ID: <20180320115409.E96A03A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/tdammers/D4394
Link       : http://ghc.haskell.org/trac/ghc/changeset/a3bdf13ca6358ca1c6f00305d33a34a9f35116cf/ghc

>---------------------------------------------------------------

commit a3bdf13ca6358ca1c6f00305d33a34a9f35116cf
Author: Richard Eisenberg <rae at cs.brynmawr.edu>
Date:   Fri Jan 26 22:09:33 2018 -0500

    Make mkNthCo take a Role parameter.
    
    Most callers of mkNthCo know the role of the coercion they
    are trying to make. So instead of calculating this role, just
    pass it in.


>---------------------------------------------------------------

a3bdf13ca6358ca1c6f00305d33a34a9f35116cf
 compiler/coreSyn/CoreLint.hs      |  11 ++-
 compiler/coreSyn/CoreOpt.hs       |  24 +++----
 compiler/coreSyn/CoreUtils.hs     |   4 +-
 compiler/iface/TcIface.hs         |   2 +-
 compiler/typecheck/TcCanonical.hs |   2 +-
 compiler/typecheck/TcEvidence.hs  |  11 +--
 compiler/typecheck/TcUnify.hs     |   4 +-
 compiler/types/Coercion.hs        | 139 ++++++++++++++++++++------------------
 compiler/types/Coercion.hs-boot   |   2 +-
 compiler/types/OptCoercion.hs     | 109 +++++++++++++-----------------
 compiler/types/TyCoRep.hs         |  11 ++-
 compiler/types/Type.hs            |   6 +-
 compiler/types/Unify.hs           |   4 +-
 13 files changed, 163 insertions(+), 166 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc a3bdf13ca6358ca1c6f00305d33a34a9f35116cf

From git at git.haskell.org  Tue Mar 20 11:54:21 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 20 Mar 2018 11:54:21 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4394: Refactored setNominalRole_maybe to
 avoid dragging role through recursion (62a38c6)
Message-ID: <20180320115421.15D4C3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/tdammers/D4394
Link       : http://ghc.haskell.org/trac/ghc/changeset/62a38c6006ffca8b6085b1e1661e686766a01a3a/ghc

>---------------------------------------------------------------

commit 62a38c6006ffca8b6085b1e1661e686766a01a3a
Author: Tobias Dammers <tdammers at gmail.com>
Date:   Mon Mar 5 12:34:30 2018 +0100

    Refactored setNominalRole_maybe to avoid dragging role through recursion


>---------------------------------------------------------------

62a38c6006ffca8b6085b1e1661e686766a01a3a
 compiler/types/Coercion.hs | 66 ++++++++++++++++++++++++----------------------
 1 file changed, 35 insertions(+), 31 deletions(-)

diff --git a/compiler/types/Coercion.hs b/compiler/types/Coercion.hs
index fbb8de9..dd4d055 100644
--- a/compiler/types/Coercion.hs
+++ b/compiler/types/Coercion.hs
@@ -1054,37 +1054,41 @@ setNominalRole_maybe :: Role -- of input coercion
                      -> Coercion -> Maybe Coercion
 setNominalRole_maybe r co
   | r == Nominal = Just co
-setNominalRole_maybe _ (SubCo co)  = Just co
-setNominalRole_maybe _ (Refl _ ty) = Just $ Refl Nominal ty
-setNominalRole_maybe _ (TyConAppCo Representational tc cos)
-  = do { cos' <- zipWithM setNominalRole_maybe (tyConRolesX Representational tc) cos
-       ; return $ TyConAppCo Nominal tc cos' }
-setNominalRole_maybe _ (FunCo Representational co1 co2)
-  = do { co1' <- setNominalRole_maybe Representational co1
-       ; co2' <- setNominalRole_maybe Representational co2
-       ; return $ FunCo Nominal co1' co2'
-       }
-setNominalRole_maybe r (SymCo co)
-  = SymCo <$> setNominalRole_maybe r co
-setNominalRole_maybe r (TransCo co1 co2)
-  = TransCo <$> setNominalRole_maybe r co1 <*> setNominalRole_maybe r co2
-setNominalRole_maybe r (AppCo co1 co2)
-  = AppCo <$> setNominalRole_maybe r co1 <*> pure co2
-setNominalRole_maybe r (ForAllCo tv kind_co co)
-  = ForAllCo tv kind_co <$> setNominalRole_maybe r co
-setNominalRole_maybe _ (NthCo _r n co)
-  = NthCo Nominal n <$> setNominalRole_maybe (coercionRole co) co
-setNominalRole_maybe r (InstCo co arg)
-  = InstCo <$> setNominalRole_maybe r co <*> pure arg
-setNominalRole_maybe r (CoherenceCo co1 co2)
-  = CoherenceCo <$> setNominalRole_maybe r co1 <*> pure co2
-setNominalRole_maybe _ (UnivCo prov _ co1 co2)
-  | case prov of UnsafeCoerceProv -> True   -- it's always unsafe
-                 PhantomProv _    -> False  -- should always be phantom
-                 ProofIrrelProv _ -> True   -- it's always safe
-                 PluginProv _     -> False  -- who knows? This choice is conservative.
-  = Just $ UnivCo prov Nominal co1 co2
-setNominalRole_maybe _ _ = Nothing
+  | otherwise = setNominalRole_maybe_helper co
+  where
+    setNominalRole_maybe_helper (SubCo co)  = Just co
+    setNominalRole_maybe_helper (Refl _ ty) = Just $ Refl Nominal ty
+    setNominalRole_maybe_helper (TyConAppCo Representational tc cos)
+      = do { cos' <- zipWithM setNominalRole_maybe (tyConRolesX Representational tc) cos
+           ; return $ TyConAppCo Nominal tc cos' }
+    setNominalRole_maybe_helper (FunCo Representational co1 co2)
+      = do { co1' <- setNominalRole_maybe Representational co1
+           ; co2' <- setNominalRole_maybe Representational co2
+           ; return $ FunCo Nominal co1' co2'
+           }
+    setNominalRole_maybe_helper (SymCo co)
+      = SymCo <$> setNominalRole_maybe_helper co
+    setNominalRole_maybe_helper (TransCo co1 co2)
+      = TransCo <$> setNominalRole_maybe_helper co1 <*> setNominalRole_maybe_helper co2
+    setNominalRole_maybe_helper (AppCo co1 co2)
+      = AppCo <$> setNominalRole_maybe_helper co1 <*> pure co2
+    setNominalRole_maybe_helper (ForAllCo tv kind_co co)
+      = ForAllCo tv kind_co <$> setNominalRole_maybe_helper co
+    setNominalRole_maybe_helper (NthCo _r n co)
+      -- NB, this case recurses via setNominalRole_maybe, not
+      -- setNominalRole_maybe_helper!
+      = NthCo Nominal n <$> setNominalRole_maybe (coercionRole co) co
+    setNominalRole_maybe_helper (InstCo co arg)
+      = InstCo <$> setNominalRole_maybe_helper co <*> pure arg
+    setNominalRole_maybe_helper (CoherenceCo co1 co2)
+      = CoherenceCo <$> setNominalRole_maybe_helper co1 <*> pure co2
+    setNominalRole_maybe_helper (UnivCo prov _ co1 co2)
+      | case prov of UnsafeCoerceProv -> True   -- it's always unsafe
+                     PhantomProv _    -> False  -- should always be phantom
+                     ProofIrrelProv _ -> True   -- it's always safe
+                     PluginProv _     -> False  -- who knows? This choice is conservative.
+      = Just $ UnivCo prov Nominal co1 co2
+    setNominalRole_maybe_helper _ = Nothing
 
 -- | Make a phantom coercion between two types. The coercion passed
 -- in must be a nominal coercion between the kinds of the


From git at git.haskell.org  Tue Mar 20 11:54:23 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 20 Mar 2018 11:54:23 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4394: Fix test to reflect changed NthCo
 ctor (c8336dd)
Message-ID: <20180320115423.CF0FA3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/tdammers/D4394
Link       : http://ghc.haskell.org/trac/ghc/changeset/c8336dd76f589779572f3da6337cd1d861934dac/ghc

>---------------------------------------------------------------

commit c8336dd76f589779572f3da6337cd1d861934dac
Author: Tobias Dammers <tdammers at gmail.com>
Date:   Tue Mar 13 13:59:36 2018 +0100

    Fix test to reflect changed NthCo ctor


>---------------------------------------------------------------

c8336dd76f589779572f3da6337cd1d861934dac
 testsuite/tests/pmcheck/should_compile/T11195.hs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/testsuite/tests/pmcheck/should_compile/T11195.hs b/testsuite/tests/pmcheck/should_compile/T11195.hs
index 236932e..0c35b4f 100644
--- a/testsuite/tests/pmcheck/should_compile/T11195.hs
+++ b/testsuite/tests/pmcheck/should_compile/T11195.hs
@@ -62,7 +62,7 @@ opt_transList :: InScopeSet -> [NormalCo] -> [NormalCo] -> [NormalCo]
 opt_transList is = zipWith (opt_trans is)
 
 opt_trans_rule :: InScopeSet -> NormalNonIdCo -> NormalNonIdCo -> Maybe NormalCo
-opt_trans_rule is in_co1@(NthCo d1 co1) in_co2@(NthCo d2 co2)
+opt_trans_rule is in_co1@(NthCo r1 d1 co1) in_co2@(NthCo r2 d2 co2)
   | d1 == d2
   , co1 `compatible_co` co2 = undefined
 


From git at git.haskell.org  Tue Mar 20 11:54:26 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 20 Mar 2018 11:54:26 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4394: Increased allocation limit for
 T5321 on OS X (9426a60)
Message-ID: <20180320115426.954233A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/tdammers/D4394
Link       : http://ghc.haskell.org/trac/ghc/changeset/9426a60c002c6c4d732e4a86cd94c2b63e71c16a/ghc

>---------------------------------------------------------------

commit 9426a60c002c6c4d732e4a86cd94c2b63e71c16a
Author: Tobias Dammers <tdammers at gmail.com>
Date:   Sat Mar 17 17:58:52 2018 +0100

    Increased allocation limit for T5321 on OS X


>---------------------------------------------------------------

9426a60c002c6c4d732e4a86cd94c2b63e71c16a
 testsuite/tests/perf/compiler/all.T | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/testsuite/tests/perf/compiler/all.T b/testsuite/tests/perf/compiler/all.T
index 2afa595..f841a68 100644
--- a/testsuite/tests/perf/compiler/all.T
+++ b/testsuite/tests/perf/compiler/all.T
@@ -549,6 +549,9 @@ test('T5321Fun',
              # 2016-04-06: 279922360 x86/Linux
              # 2017-03-24: 244387620 x86/Linux (64-bit machine)
 
+            (platform('x86_64-apple-darwin'), 446893600, 5),
+             # 2018-03-17: 423774560     #  OS X-only (reason unknown, see #11753)
+
             (wordsize(64), 423774560, 5)])
              # prev:       585521080
              # 2012-08-29: 713385808     #  (increase due to new codegen)


From git at git.haskell.org  Tue Mar 20 16:08:33 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 20 Mar 2018 16:08:33 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4394: Fix rebasing mistake (29f2710)
Message-ID: <20180320160833.A48873A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/tdammers/D4394
Link       : http://ghc.haskell.org/trac/ghc/changeset/29f2710c45fd33c5d09a3a09bfdc4ec9c237fa35/ghc

>---------------------------------------------------------------

commit 29f2710c45fd33c5d09a3a09bfdc4ec9c237fa35
Author: Tobias Dammers <tdammers at gmail.com>
Date:   Tue Mar 20 17:08:01 2018 +0100

    Fix rebasing mistake


>---------------------------------------------------------------

29f2710c45fd33c5d09a3a09bfdc4ec9c237fa35
 compiler/types/TyCoRep.hs | 4 ----
 libraries/array           | 2 +-
 2 files changed, 1 insertion(+), 5 deletions(-)

diff --git a/compiler/types/TyCoRep.hs b/compiler/types/TyCoRep.hs
index dccde49..e924e04 100644
--- a/compiler/types/TyCoRep.hs
+++ b/compiler/types/TyCoRep.hs
@@ -825,10 +825,6 @@ data Coercion
   | SymCo Coercion             -- :: e -> e
   | TransCo Coercion Coercion  -- :: e -> e -> e
 
-    -- The number coercions should match exactly the expectations
-    -- of the CoAxiomRule (i.e., the rule is fully saturated).
-  | AxiomRuleCo CoAxiomRule [Coercion]
-
   | NthCo  Role Int Coercion     -- Zero-indexed; decomposes (T t0 ... tn)
     -- :: "e" -> _ -> e0 -> e (inverse of TyConAppCo, see Note [TyConAppCo roles])
     -- Using NthCo on a ForAllCo gives an N coercion always
diff --git a/libraries/array b/libraries/array
index 1d0435f..9d63218 160000
--- a/libraries/array
+++ b/libraries/array
@@ -1 +1 @@
-Subproject commit 1d0435f4937f03901e32304e279f46ce19b0f089
+Subproject commit 9d63218fd067ff4885c0efa43b388238421a5c89


From git at git.haskell.org  Tue Mar 20 16:18:32 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 20 Mar 2018 16:18:32 +0000 (UTC)
Subject: [commit: ghc] master: Revert "rts,
 base: Refactor stats.c to improve --machine-readable report" (0a778eb)
Message-ID: <20180320161832.8069F3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/0a778ebeccefe6c3c2540a06d5a1c585f18e01ab/ghc

>---------------------------------------------------------------

commit 0a778ebeccefe6c3c2540a06d5a1c585f18e01ab
Author: Ben Gamari <ben at smart-cactus.org>
Date:   Tue Mar 20 12:17:43 2018 -0400

    Revert "rts, base: Refactor stats.c to improve --machine-readable report"
    
    This reverts commit 2d4bda2e4ac68816baba0afab00da6f769ea75a7.


>---------------------------------------------------------------

0a778ebeccefe6c3c2540a06d5a1c585f18e01ab
 includes/RtsAPI.h            |  34 +-
 libraries/base/GHC/Stats.hsc |   8 -
 rts/Stats.c                  | 921 ++++++++++++++-----------------------------
 rts/Stats.h                  |  45 ---
 4 files changed, 317 insertions(+), 691 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc 0a778ebeccefe6c3c2540a06d5a1c585f18e01ab

From git at git.haskell.org  Tue Mar 20 17:42:24 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 20 Mar 2018 17:42:24 +0000 (UTC)
Subject: [commit: ghc] master: Fix seq# case of exprOkForSpeculation (abaf43d)
Message-ID: <20180320174224.141283A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/abaf43d9d88d6fdf7345b936a571d17cfe1fa140/ghc

>---------------------------------------------------------------

commit abaf43d9d88d6fdf7345b936a571d17cfe1fa140
Author: Simon Peyton Jones <simonpj at microsoft.com>
Date:   Tue Mar 20 16:30:01 2018 +0000

    Fix seq# case of exprOkForSpeculation
    
    This subtle patch fixes Trac #5129 (again; comment:20
    and following).
    
    I took the opportunity to document seq# properly; see
    Note [seq# magic] in PrelRules, and Note [seq# and expr_ok]
    in CoreUtils.


>---------------------------------------------------------------

abaf43d9d88d6fdf7345b936a571d17cfe1fa140
 compiler/codeGen/StgCmmExpr.hs           | 15 ++++++----
 compiler/coreSyn/CoreUtils.hs            | 24 ++++++++++++++-
 compiler/prelude/PrelRules.hs            | 51 +++++++++++++++++++++++++++++++-
 compiler/prelude/primops.txt.pp          |  8 +----
 testsuite/tests/codeGen/should_run/all.T |  2 +-
 5 files changed, 84 insertions(+), 16 deletions(-)

diff --git a/compiler/codeGen/StgCmmExpr.hs b/compiler/codeGen/StgCmmExpr.hs
index c2f2efe..22fcfaf 100644
--- a/compiler/codeGen/StgCmmExpr.hs
+++ b/compiler/codeGen/StgCmmExpr.hs
@@ -60,7 +60,8 @@ cgExpr  :: StgExpr -> FCode ReturnKind
 
 cgExpr (StgApp fun args)     = cgIdApp fun args
 
-{- seq# a s ==> a -}
+-- seq# a s ==> a
+-- See Note [seq# magic] in PrelRules
 cgExpr (StgOpApp (StgPrimOp SeqOp) [StgVarArg a, _] _res_ty) =
   cgIdApp a []
 
@@ -447,13 +448,14 @@ cgCase scrut@(StgApp v []) _ (PrimAlt _) _
 
 {- Note [Handle seq#]
 ~~~~~~~~~~~~~~~~~~~~~
-case seq# a s of v
-  (# s', a' #) -> e
+See Note [seq# magic] in PrelRules.
+The special case for seq# in cgCase does this:
 
+  case seq# a s of v
+    (# s', a' #) -> e
 ==>
-
-case a of v
-  (# s', a' #) -> e
+  case a of v
+    (# s', a' #) -> e
 
 (taking advantage of the fact that the return convention for (# State#, a #)
 is the same as the return convention for just 'a')
@@ -461,6 +463,7 @@ is the same as the return convention for just 'a')
 
 cgCase (StgOpApp (StgPrimOp SeqOp) [StgVarArg a, _] _) bndr alt_type alts
   = -- Note [Handle seq#]
+    -- And see Note [seq# magic] in PrelRules
     -- Use the same return convention as vanilla 'a'.
     cgCase (StgApp a []) bndr alt_type alts
 
diff --git a/compiler/coreSyn/CoreUtils.hs b/compiler/coreSyn/CoreUtils.hs
index 4db9d8f..5608afc 100644
--- a/compiler/coreSyn/CoreUtils.hs
+++ b/compiler/coreSyn/CoreUtils.hs
@@ -1449,8 +1449,11 @@ app_ok primop_ok fun args
               -- Often there is a literal divisor, and this
               -- can get rid of a thunk in an inner loop
 
+        | SeqOp <- op    -- See Note [seq# and expr_ok]
+        -> all (expr_ok primop_ok) args
+
         | otherwise
-        -> primop_ok op     -- Check the primop itself
+        -> primop_ok op  -- Check the primop itself
         && and (zipWith arg_ok arg_tys args)  -- Check the arguments
 
       _other -> isUnliftedType (idType fun)          -- c.f. the Var case of exprIsHNF
@@ -1607,6 +1610,25 @@ See also Note [dataToTag#] in primops.txt.pp.
 
 Bottom line:
   * in exprOkForSpeculation we simply ignore all lifted arguments.
+  * except see Note [seq# and expr_ok] for an exception
+
+
+Note [seq# and expr_ok]
+~~~~~~~~~~~~~~~~~~~~~~~
+Recall that
+   seq# :: forall a s . a -> State# s -> (# State# s, a #)
+must always evaluate its first argument.  So it's really a
+counter-example to Note [Primops with lifted arguments]. In
+the case of seq# we must check the argument to seq#.  Remember
+item (d) of the specification of exprOkForSpeculation:
+
+  -- Precisely, it returns @True@ iff:
+  --  a) The expression guarantees to terminate,
+         ...
+  --  d) without throwing a Haskell exception
+
+The lack of this special case caused Trac #5129 to go bad again.
+See comment:24 and following
 
 
 ************************************************************************
diff --git a/compiler/prelude/PrelRules.hs b/compiler/prelude/PrelRules.hs
index 73484b7..14e3f0f 100644
--- a/compiler/prelude/PrelRules.hs
+++ b/compiler/prelude/PrelRules.hs
@@ -942,7 +942,56 @@ dataToTagRule = a `mplus` b
 ************************************************************************
 -}
 
--- seq# :: forall a s . a -> State# s -> (# State# s, a #)
+{- Note [seq# magic]
+~~~~~~~~~~~~~~~~~~~~
+The primop
+   seq# :: forall a s . a -> State# s -> (# State# s, a #)
+
+is /not/ the same as the Prelude function seq :: a -> b -> b
+as you can see from its type.  In fact, seq# is the implementation
+mechanism for 'evaluate'
+
+   evaluate :: a -> IO a
+   evaluate a = IO $ \s -> seq# a s
+
+The semantics of seq# is
+  * evaluate its first argument
+  * and return it
+
+Things to note
+
+* Why do we need a primop at all?  That is, instead of
+      case seq# x s of (# x, s #) -> blah
+  why not instead say this?
+      case x of { DEFAULT -> blah)
+
+  Reason (see Trac #5129): if we saw
+    catch# (\s -> case x of { DEFAULT -> raiseIO# exn s }) handler
+
+  then we'd drop the 'case x' because the body of the case is bottom
+  anyway. But we don't want to do that; the whole /point/ of
+  seq#/evaluate is to evaluate 'x' first in the IO monad.
+
+  In short, we /always/ evaluate the first argument and never
+  just discard it.
+
+* Why return the value?  So that we can control sharing of seq'd
+  values: in
+     let x = e in x `seq` ... x ...
+  We don't want to inline x, so better to represent it as
+       let x = e in case seq# x RW of (# _, x' #) -> ... x' ...
+  also it matches the type of rseq in the Eval monad.
+
+Implementing seq#.  The compiler has magic for SeqOp in
+
+- PrelRules.seqRule: eliminate (seq# <whnf> s)
+
+- StgCmmExpr.cgExpr, and cgCase: special case for seq#
+
+- CoreUtils.exprOkForSpeculation;
+  see Note [seq# and expr_ok] in CoreUtils
+-}
+
 seqRule :: RuleM CoreExpr
 seqRule = do
   [Type ty_a, Type _ty_s, a, s] <- getArgs
diff --git a/compiler/prelude/primops.txt.pp b/compiler/prelude/primops.txt.pp
index e580f98..996e0bb 100644
--- a/compiler/prelude/primops.txt.pp
+++ b/compiler/prelude/primops.txt.pp
@@ -2697,13 +2697,7 @@ primop SparkOp "spark#" GenPrimOp
 
 primop SeqOp "seq#" GenPrimOp
    a -> State# s -> (# State# s, a #)
-
-   -- why return the value?  So that we can control sharing of seq'd
-   -- values: in
-   --    let x = e in x `seq` ... x ...
-   -- we don't want to inline x, so better to represent it as
-   --    let x = e in case seq# x RW of (# _, x' #) -> ... x' ...
-   -- also it matches the type of rseq in the Eval monad.
+   -- See Note [seq# magic] in PrelRules
 
 primop GetSparkOp "getSpark#" GenPrimOp
    State# s -> (# State# s, Int#, a #)
diff --git a/testsuite/tests/codeGen/should_run/all.T b/testsuite/tests/codeGen/should_run/all.T
index cf4904e..55386e4 100644
--- a/testsuite/tests/codeGen/should_run/all.T
+++ b/testsuite/tests/codeGen/should_run/all.T
@@ -94,7 +94,7 @@ test('T5149', omit_ways(['ghci']), multi_compile_and_run,
 test('T5129',
      # The bug is in simplifier when run with -O1 and above, so only run it
      # optimised, using any backend.
-     [ only_ways(['optasm']), expect_broken(5129) ],
+     only_ways(['optasm']),
      compile_and_run, [''])
 
 test('T5626', exit_code(1), compile_and_run, [''])


From git at git.haskell.org  Tue Mar 20 22:20:46 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 20 Mar 2018 22:20:46 +0000 (UTC)
Subject: [commit: ghc] branch 'wip/T14951' created
Message-ID: <20180320222046.EA9593A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

New branch : wip/T14951
Referencing: b855db7e70dc9ead1b09fe02d2483b0a01ab9609

From git at git.haskell.org  Tue Mar 20 22:20:49 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 20 Mar 2018 22:20:49 +0000 (UTC)
Subject: [commit: ghc] wip/T14951: Create stronger ArgOccs from calls to
 specialized functions (a5555df)
Message-ID: <20180320222049.B786F3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/T14951
Link       : http://ghc.haskell.org/trac/ghc/changeset/a5555df43d8c15273add6bd1d30ca4051627935b/ghc

>---------------------------------------------------------------

commit a5555df43d8c15273add6bd1d30ca4051627935b
Author: Joachim Breitner <mail at joachim-breitner.de>
Date:   Tue Mar 20 13:42:59 2018 -0400

    Create stronger ArgOccs from calls to specialized functions


>---------------------------------------------------------------

a5555df43d8c15273add6bd1d30ca4051627935b
 compiler/specialise/SpecConstr.hs | 32 +++++++++++++++++++++++++++++++-
 1 file changed, 31 insertions(+), 1 deletion(-)

diff --git a/compiler/specialise/SpecConstr.hs b/compiler/specialise/SpecConstr.hs
index d54c1ea..f0a03a8 100644
--- a/compiler/specialise/SpecConstr.hs
+++ b/compiler/specialise/SpecConstr.hs
@@ -57,6 +57,7 @@ import UniqFM
 import MonadUtils
 import Control.Monad    ( zipWithM )
 import Data.List
+import Data.Maybe       ( fromMaybe )
 import PrelNames        ( specTyConName )
 import Module
 import TyCon ( TyCon )
@@ -1496,6 +1497,7 @@ data OneSpec =
   OS { os_pat  :: CallPat    -- Call pattern that generated this specialisation
      , os_rule :: CoreRule   -- Rule connecting original id with the specialisation
      , os_id   :: OutId      -- Spec id
+     , os_orig_id :: OutId   -- The original id
      , os_rhs  :: OutExpr }  -- Spec rhs
 
 noSpecInfo :: SpecInfo
@@ -1520,8 +1522,22 @@ specRec :: TopLevelFlag -> ScEnv
                                            --     plus details of specialisations
 
 specRec top_lvl env body_usg rhs_infos
-  = go 1 seed_calls nullUsage init_spec_infos
+  = add_pat_usages <$>
+    go 1 seed_calls nullUsage init_spec_infos
   where
+    -- Calculate the stronger demand on all all arguments to fn that
+    -- is useful once we have this specialization
+    add_pat_usages (usg, spec_infos) = (usg `combineUsage` extra_usages, spec_infos)
+      where extra_usages = combineUsages
+                [ patToCallUsage env call_pat call
+                | si <- spec_infos
+                , os <- si_specs si
+                , let fn  = os_orig_id os
+                      call_pat = os_pat os
+                , pprTrace "add_pat_usages" (ppr fn <+> ppr call_pat)  True
+                , call <- fromMaybe [] $ lookupVarEnv all_calls fn
+                ]
+
     (seed_calls, init_spec_infos)    -- Note [Seeding top-level recursive groups]
        | isTopLevel top_lvl
        , any (isExportedId . ri_fn) rhs_infos   -- Seed from body and RHSs
@@ -1741,8 +1757,22 @@ spec_one env fn arg_bndrs body (call_pat@(qvars, pats), rule_number)
                            -- See Note [Transfer activation]
         ; return (spec_usg, OS { os_pat = call_pat, os_rule = rule
                                , os_id = spec_id
+                               , os_orig_id = fn
                                , os_rhs = spec_rhs }) }
 
+patToCallUsage :: ScEnv -> CallPat -> Call -> ScUsage
+patToCallUsage env (_qvars, pats) (Call _ args _)
+    = pprTrace "patToCallUsage" (ppr pats <+> ppr args <+> ppr usage) $
+      usage
+  where
+    usage = combineUsages $ zipWith go pats args
+    go e at App{} (Var v)
+        | (Var f, args) <- collectArgs e
+        , Just dc <- isDataConWorkId_maybe f
+        , Just RecArg <- lookupHowBound env v
+        = let dc_usage = unitUFM dc (map (const UnkOcc) args)
+          in  nullUsage { scu_occs = unitVarEnv v (ScrutOcc dc_usage) }
+    go _ _ = nullUsage
 
 -- See Note [Strictness information in worker binders]
 handOutStrictnessInformation :: [Demand] -> [Var] -> [Var]


From git at git.haskell.org  Tue Mar 20 22:20:52 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 20 Mar 2018 22:20:52 +0000 (UTC)
Subject: [commit: ghc] wip/T14951: Improve and write Note about cascading
 specialization (b855db7)
Message-ID: <20180320222052.818C63A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/T14951
Link       : http://ghc.haskell.org/trac/ghc/changeset/b855db7e70dc9ead1b09fe02d2483b0a01ab9609/ghc

>---------------------------------------------------------------

commit b855db7e70dc9ead1b09fe02d2483b0a01ab9609
Author: Joachim Breitner <mail at joachim-breitner.de>
Date:   Tue Mar 20 15:48:29 2018 -0400

    Improve and write Note about cascading specialization


>---------------------------------------------------------------

b855db7e70dc9ead1b09fe02d2483b0a01ab9609
 compiler/specialise/SpecConstr.hs | 72 +++++++++++++++++++++++++++++++++++----
 1 file changed, 66 insertions(+), 6 deletions(-)

diff --git a/compiler/specialise/SpecConstr.hs b/compiler/specialise/SpecConstr.hs
index f0a03a8..44fdf66 100644
--- a/compiler/specialise/SpecConstr.hs
+++ b/compiler/specialise/SpecConstr.hs
@@ -1760,20 +1760,44 @@ spec_one env fn arg_bndrs body (call_pat@(qvars, pats), rule_number)
                                , os_orig_id = fn
                                , os_rhs = spec_rhs }) }
 
+-- See Note [ArgOcc from calls to specialized functions]
 patToCallUsage :: ScEnv -> CallPat -> Call -> ScUsage
 patToCallUsage env (_qvars, pats) (Call _ args _)
     = pprTrace "patToCallUsage" (ppr pats <+> ppr args <+> ppr usage) $
       usage
   where
     usage = combineUsages $ zipWith go pats args
-    go e at App{} (Var v)
-        | (Var f, args) <- collectArgs e
-        , Just dc <- isDataConWorkId_maybe f
-        , Just RecArg <- lookupHowBound env v
-        = let dc_usage = unitUFM dc (map (const UnkOcc) args)
-          in  nullUsage { scu_occs = unitVarEnv v (ScrutOcc dc_usage) }
+
+    go :: CoreExpr -> CoreExpr -> ScUsage
+    -- The interesting case
+    go pat (Var v)
+        | Just RecArg <- lookupHowBound env v
+        , arg_occ at ScrutOcc{} <- patToArgOcc pat -- skip if we get UnkOcc
+        = nullUsage { scu_occs = unitVarEnv v arg_occ }
+
+    -- Transparent cases
+    go (Tick _ p) e = go p e
+    go (Cast p _) e = go p e
+    go p (Tick _ e) = go p e
+    go p (Cast e _) = go p e
+
+
+    -- Traverse the tree
+    go (App pf pa) (App f a)
+        = go pf f `combineUsage` go pa a
+
+    -- Boring catch-all
     go _ _ = nullUsage
 
+patToArgOcc :: CoreExpr -> ArgOcc
+patToArgOcc e at App{}
+    | (Var f, args) <- collectArgs e
+    , Just dc <- isDataConWorkId_maybe f
+    = let arg_occs = [ patToArgOcc arg | arg <- args, not (isTypeArg arg) ]
+      in ScrutOcc $ unitUFM dc arg_occs
+patToArgOcc _
+    = UnkOcc
+
 -- See Note [Strictness information in worker binders]
 handOutStrictnessInformation :: [Demand] -> [Var] -> [Var]
 handOutStrictnessInformation = go
@@ -1809,6 +1833,42 @@ calcSpecStrictness fn qvars pats
     go_one env _         _ = env
 
 {-
+Note [ArgOcc from calls to specialized functions]
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+We collect the ArgOcc to find out which parameters are being scrutinized in the
+body function, and only generate specializations when they would lead to some
+optimization: In
+
+  foo x = … case x of (a,b) -> …
+
+We are willing to specialize foo. If we have
+
+  foo x = … bar x …
+    where bar y = …
+
+we normally don’t. But what if we specialize bar? Then we have
+
+  foo x = … bar x …
+    where $sbar a b = …
+          bar y = …
+          {-# RULE forall a b. bar (a,b) = $sbar a b #-}
+
+and now it would be beneficial to create a specialized version of foo that
+calls $sbar directly.
+
+To achieve this, after we specialize bar, we look at the calls to it (found in
+scu_calls), and all the specializations that we created. If there is a call `bar x`
+and a specialization pattern `(x,y)`, then we treat that as if we found a case
+analysis of x, and include `x ↦ ScrutOcc` in scu_occs. This unblocks specialization
+of foo, and so on.
+
+(We might want to generalize this to any call to `baz x` where `baz` has
+rewrite rules that match on constructor arguments, not only for when _we_ _just_
+created specializations.)
+
+(See #14951)
+
 Note [spec_usg includes rhs_usg]
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 In calls to 'specialise', the returned ScUsage must include the rhs_usg in


From git at git.haskell.org  Wed Mar 21 13:18:22 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Wed, 21 Mar 2018 13:18:22 +0000 (UTC)
Subject: [commit: ghc] master: Fix #14869 by being more mindful of Type vs.
 Constraint (49ac3f0)
Message-ID: <20180321131822.A40703A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/49ac3f0f2a13f66fea31a258fa98b0de39bfbf10/ghc

>---------------------------------------------------------------

commit 49ac3f0f2a13f66fea31a258fa98b0de39bfbf10
Author: Ryan Scott <ryan.gl.scott at gmail.com>
Date:   Wed Mar 21 08:59:28 2018 -0400

    Fix #14869 by being more mindful of Type vs. Constraint
    
    Summary:
    Before, we were using `isLiftedTypeKind` in `reifyType`
    before checking if a type was `Constraint`. But as it turns out,
    `isLiftedTypeKind` treats `Constraint` the same as `Type`, so every
    occurrence of `Constraint` would be reified as `Type`! To make things
    worse, the documentation for `isLiftedTypeKind` stated that it
    treats `Constraint` //differently// from `Type`, which simply isn't
    true.
    
    This revises the documentation for `isLiftedTypeKind` to reflect
    reality, and defers the `isLiftedTypeKind` check in `reifyType` so
    that it does not accidentally swallow `Constraint`.
    
    Test Plan: make test TEST=T14869
    
    Reviewers: goldfire, bgamari
    
    Reviewed By: goldfire
    
    Subscribers: rwbarton, thomie, carter
    
    GHC Trac Issues: #14869
    
    Differential Revision: https://phabricator.haskell.org/D4474


>---------------------------------------------------------------

49ac3f0f2a13f66fea31a258fa98b0de39bfbf10
 compiler/typecheck/TcSplice.hs   |  7 ++++--
 compiler/types/Kind.hs           | 31 +++++++++++++--------------
 compiler/types/TyCoRep.hs        | 46 ++++++++++++++++++++++++++++++----------
 testsuite/tests/th/T14869.hs     | 25 ++++++++++++++++++++++
 testsuite/tests/th/T14869.stderr | 17 +++++++++++++++
 testsuite/tests/th/all.T         |  2 ++
 6 files changed, 99 insertions(+), 29 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc 49ac3f0f2a13f66fea31a258fa98b0de39bfbf10

From git at git.haskell.org  Wed Mar 21 19:42:32 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Wed, 21 Mar 2018 19:42:32 +0000 (UTC)
Subject: [commit: ghc] wip/T14951: Do cascading SpecConstr also for
 non-recursive bindings (0aa7d87)
Message-ID: <20180321194232.70C363A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/T14951
Link       : http://ghc.haskell.org/trac/ghc/changeset/0aa7d8796a95298e906ea81fe4a52590d75c2e47/ghc

>---------------------------------------------------------------

commit 0aa7d8796a95298e906ea81fe4a52590d75c2e47
Author: Joachim Breitner <mail at joachim-breitner.de>
Date:   Wed Mar 21 15:29:15 2018 -0400

    Do cascading SpecConstr also for non-recursive bindings
    
    just for the sake of consistency, and clean up the code a bit.


>---------------------------------------------------------------

0aa7d8796a95298e906ea81fe4a52590d75c2e47
 compiler/specialise/SpecConstr.hs | 36 +++++++++++++++++++++---------------
 1 file changed, 21 insertions(+), 15 deletions(-)

diff --git a/compiler/specialise/SpecConstr.hs b/compiler/specialise/SpecConstr.hs
index 44fdf66..ab2490e 100644
--- a/compiler/specialise/SpecConstr.hs
+++ b/compiler/specialise/SpecConstr.hs
@@ -1511,7 +1511,8 @@ specNonRec :: ScEnv
                                                --     plus details of specialisations
 
 specNonRec env body_usg rhs_info
-  = specialise env (scu_calls body_usg) rhs_info
+  = addPatUsages env (scu_calls body_usg) <$>
+    specialise env (scu_calls body_usg) rhs_info
                (noSpecInfo { si_mb_unspec = Just (ri_rhs_usg rhs_info) })
 
 ----------------------
@@ -1522,22 +1523,9 @@ specRec :: TopLevelFlag -> ScEnv
                                            --     plus details of specialisations
 
 specRec top_lvl env body_usg rhs_infos
-  = add_pat_usages <$>
+  = addPatUsagess env (scu_calls body_usg) <$>
     go 1 seed_calls nullUsage init_spec_infos
   where
-    -- Calculate the stronger demand on all all arguments to fn that
-    -- is useful once we have this specialization
-    add_pat_usages (usg, spec_infos) = (usg `combineUsage` extra_usages, spec_infos)
-      where extra_usages = combineUsages
-                [ patToCallUsage env call_pat call
-                | si <- spec_infos
-                , os <- si_specs si
-                , let fn  = os_orig_id os
-                      call_pat = os_pat os
-                , pprTrace "add_pat_usages" (ppr fn <+> ppr call_pat)  True
-                , call <- fromMaybe [] $ lookupVarEnv all_calls fn
-                ]
-
     (seed_calls, init_spec_infos)    -- Note [Seeding top-level recursive groups]
        | isTopLevel top_lvl
        , any (isExportedId . ri_fn) rhs_infos   -- Seed from body and RHSs
@@ -1761,6 +1749,24 @@ spec_one env fn arg_bndrs body (call_pat@(qvars, pats), rule_number)
                                , os_rhs = spec_rhs }) }
 
 -- See Note [ArgOcc from calls to specialized functions]
+addPatUsagess :: ScEnv -> CallEnv -> (ScUsage, [SpecInfo]) -> (ScUsage, [SpecInfo])
+addPatUsagess env body_calls (usg, spec_infos) = (usg `combineUsage` extra_usages, spec_infos)
+  where extra_usages = combineUsages [ extraPatUsages env body_calls si | si <- spec_infos ]
+
+addPatUsages :: ScEnv -> CallEnv -> (ScUsage, SpecInfo) -> (ScUsage, SpecInfo)
+addPatUsages env body_calls (usg, spec_info) = (usg `combineUsage` extra_usage, spec_info)
+  where extra_usage = extraPatUsages env body_calls spec_info
+
+extraPatUsages :: ScEnv -> CallEnv -> SpecInfo -> ScUsage
+extraPatUsages env body_calls si  = combineUsages
+    [ patToCallUsage env call_pat call
+    | os <- si_specs si
+    , let fn  = os_orig_id os
+          call_pat = os_pat os
+    , pprTrace "add_pat_usages" (ppr fn <+> ppr call_pat)  True
+    , call <- fromMaybe [] $ lookupVarEnv body_calls fn
+    ]
+
 patToCallUsage :: ScEnv -> CallPat -> Call -> ScUsage
 patToCallUsage env (_qvars, pats) (Call _ args _)
     = pprTrace "patToCallUsage" (ppr pats <+> ppr args <+> ppr usage) $


From git at git.haskell.org  Wed Mar 21 21:25:36 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Wed, 21 Mar 2018 21:25:36 +0000 (UTC)
Subject: [commit: ghc] wip/T14068: Run SpecConstr only once again (c663b71)
Message-ID: <20180321212536.83F163A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/T14068
Link       : http://ghc.haskell.org/trac/ghc/changeset/c663b715b6201d460e8bf2b6fb26e61c700384e0/ghc

>---------------------------------------------------------------

commit c663b715b6201d460e8bf2b6fb26e61c700384e0
Author: Joachim Breitner <mail at joachim-breitner.de>
Date:   Tue Mar 20 13:42:31 2018 -0400

    Run SpecConstr only once again


>---------------------------------------------------------------

c663b715b6201d460e8bf2b6fb26e61c700384e0
 compiler/simplCore/SimplCore.hs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/compiler/simplCore/SimplCore.hs b/compiler/simplCore/SimplCore.hs
index 9f260a6..41f0a9a 100644
--- a/compiler/simplCore/SimplCore.hs
+++ b/compiler/simplCore/SimplCore.hs
@@ -344,9 +344,9 @@ getCoreToDo dflags
 
         runWhen spec_constr CoreDoSpecConstr,
 
-        simpl_phase 0 ["between-core-spec"] max_iter,
+        -- simpl_phase 0 ["between-core-spec"] max_iter,
 
-        runWhen spec_constr CoreDoSpecConstr,
+        -- runWhen spec_constr CoreDoSpecConstr,
 
         maybe_rule_check (Phase 0),
 


From git at git.haskell.org  Wed Mar 21 21:25:39 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Wed, 21 Mar 2018 21:25:39 +0000 (UTC)
Subject: [commit: ghc] wip/T14068: Merge branch 'wip/T14951' into wip/T14068
 (4a47fd3)
Message-ID: <20180321212539.7FC123A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/T14068
Link       : http://ghc.haskell.org/trac/ghc/changeset/4a47fd33d2f16070d4fe8bd32a104587608061cd/ghc

>---------------------------------------------------------------

commit 4a47fd33d2f16070d4fe8bd32a104587608061cd
Merge: c663b71 0aa7d87
Author: Joachim Breitner <mail at joachim-breitner.de>
Date:   Wed Mar 21 17:02:21 2018 -0400

    Merge branch 'wip/T14951' into wip/T14068



>---------------------------------------------------------------


Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc 4a47fd33d2f16070d4fe8bd32a104587608061cd

From git at git.haskell.org  Wed Mar 21 21:25:41 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Wed, 21 Mar 2018 21:25:41 +0000 (UTC)
Subject: [commit: ghc] wip/T14068's head updated: Merge branch 'wip/T14951'
 into wip/T14068 (4a47fd3)
Message-ID: <20180321212541.D4AEA3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

Branch 'wip/T14068' now includes:

     2a3702d Comments and tiny refactor
     5a1ad23 Update test for #5129:
     f9a6d42 Add a build with 32bit Ubuntu container
     2918abf rts: Add --internal-counters RTS flag and several counters
     3d378d9 Also check local rules with -frules-check
     39c7406 Be more selective in which conditionals we invert
     fad822e Improve the warning message of qualified unused imports.
     0db0e46 Get rid of more CPP in cmm/ and codeGen/
     bbcea13 Hoopl: improve postorder calculation
     a00b88b Implement -dword-hex-literals
     b37a87b PPC nativeGen: Add support for MO_SS_Conv_W32_W64
     5241f29 SPARC nativeGen: Support for MO_SS_Conv_W32_W64
     d27336e [RFC] nativeGen: Add support for MO_SS_Conv_W32_W64 on i386
     20cbb01 Improve accuracy of get/setAllocationCounter
     256577f CmmUtils: get rid of insertBlock
     fbd9b88 Implement equalKeysUFM the right way
     9868f91 Turn a TH Name for built-in syntax into an unqualified RdrName
     e358854 Require GHC 8.2 to bootstrap GHC
     c3aea39 Fix #14934 by including axSub0R in typeNatCoAxiomRules
     f748c52 Don't permit data types with return kind Constraint
     fdec06a Update tests for #12870 to pass with a slow run of the testsuite.
     98c1f22 Bump array submodule
     960cd42 Fix typo in user guide about ConstraintKinds
     82e8d1f Fix typo
     b3b394b gen-data-layout.sh: Use bash array for readability
     2d4bda2 rts, base: Refactor stats.c to improve --machine-readable report
     afad556 Add -flate-specialise which runs a later specialisation pass
     6a71ef7 Bump autoconf version bound to >= 2.69
     d718023 relnotes: Fix parsing of Version: field from Cabal file
     60aa53d configure: Accept version suffix in solaris name
     57001d9 Update T5129 test:
     0a778eb Revert "rts, base: Refactor stats.c to improve --machine-readable report"
     abaf43d Fix seq# case of exprOkForSpeculation
     c663b71 Run SpecConstr only once again
     a5555df Create stronger ArgOccs from calls to specialized functions
     b855db7 Improve and write Note about cascading specialization
     0aa7d87 Do cascading SpecConstr also for non-recursive bindings
     4a47fd3 Merge branch 'wip/T14951' into wip/T14068

From git at git.haskell.org  Thu Mar 22 08:25:19 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Thu, 22 Mar 2018 08:25:19 +0000 (UTC)
Subject: [commit: ghc] master: Fix two obscure bugs in rule matching (3446cee)
Message-ID: <20180322082519.21A3D3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/3446cee05e08d78033e141fa46d4de6929542cbb/ghc

>---------------------------------------------------------------

commit 3446cee05e08d78033e141fa46d4de6929542cbb
Author: Simon Peyton Jones <simonpj at microsoft.com>
Date:   Wed Mar 21 17:25:23 2018 +0000

    Fix two obscure bugs in rule matching
    
    This patch fixes Trac #14777, a compiler crash.
    
    There were actually two bugs.
    
    1. In Rules.matchN, I was (consciously) not rename the template binders
       of the rule. Sadly, in rare cases an accidental coincidence of
       uniques could mean that a term variable was mapped to a type
       variable, utterly bogusly.  See "Historical note" in
       Note [Cloning the template binders] in Rules.
    
       This was hard to find, but easy to fix.
    
    2. The fix to (1) showed up a bug in Unify.hs.  The test in
       Unify.tvBindFlag was previously using the domain of the RnEnv2
       to detect locally-bound variables (e.g. when unifying under
       a forall).  That's fine when teh RnEnv2 starts empty, as it
       does in most entry points.  But the tcMatchTyKisX entry point,
       used from the rule matcher, passes in a non-empty RnEnv2 (by
       design).  Now the domain of the RnEnv doesn't idenfity those
       locally-bound variables any more :-(.
    
       Solution: extend UmEnv with a new field um_skols, to capture
       the skolems directly.  Simple, easy, works.


>---------------------------------------------------------------

3446cee05e08d78033e141fa46d4de6929542cbb
 compiler/specialise/Rules.hs | 153 +++++++++++++++++++++++++------------------
 compiler/types/Unify.hs      | 121 ++++++++++++++++++----------------
 2 files changed, 154 insertions(+), 120 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc 3446cee05e08d78033e141fa46d4de6929542cbb

From git at git.haskell.org  Thu Mar 22 08:25:21 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Thu, 22 Mar 2018 08:25:21 +0000 (UTC)
Subject: [commit: ghc] master: Allow as-patterns in unidirectional patttern
 synonyms (411a97e)
Message-ID: <20180322082521.E52403A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/411a97e2c0083529b4259d0cad8f453bae110dee/ghc

>---------------------------------------------------------------

commit 411a97e2c0083529b4259d0cad8f453bae110dee
Author: Simon Peyton Jones <simonpj at microsoft.com>
Date:   Wed Mar 21 17:21:15 2018 +0000

    Allow as-patterns in unidirectional patttern synonyms
    
    This patch implements GHC Proposal #94, described here
       https://github.com/ghc-proposals/ghc-proposals/pull/94
    
    The effect is simply to lift a totally-undocumented restriction to
    unidirecional pattern synonyms, namely that they can't have as-patterns
    or n+k patterns.
    
    The fix is easy: just remove the checks.
    
    I also took the opportunity to improve the manual entry for
    the semantics of pattern matching for pattern synonyms.


>---------------------------------------------------------------

411a97e2c0083529b4259d0cad8f453bae110dee
 compiler/typecheck/TcPatSyn.hs                     | 65 ----------------------
 docs/users_guide/glasgow_exts.rst                  | 18 ++++++
 testsuite/tests/patsyn/should_fail/all.T           |  2 +-
 testsuite/tests/patsyn/should_fail/as-pattern.hs   |  1 +
 .../tests/patsyn/should_fail/as-pattern.stderr     |  5 --
 5 files changed, 20 insertions(+), 71 deletions(-)

diff --git a/compiler/typecheck/TcPatSyn.hs b/compiler/typecheck/TcPatSyn.hs
index 1e2d85e..9c8880e 100644
--- a/compiler/typecheck/TcPatSyn.hs
+++ b/compiler/typecheck/TcPatSyn.hs
@@ -72,7 +72,6 @@ tcInferPatSynDecl PSB{ psb_id = lname@(L _ name), psb_args = details,
                        psb_def = lpat, psb_dir = dir }
   = addPatSynCtxt lname $
     do { traceTc "tcInferPatSynDecl {" $ ppr name
-       ; tcCheckPatSynPat lpat
 
        ; let (arg_names, rec_fields, is_infix) = collectPatSynArgInfo details
        ; (tclvl, wanted, ((lpat', args), pat_ty))
@@ -250,8 +249,6 @@ tcCheckPatSynDecl psb at PSB{ psb_id = lname@(L _ name), psb_args = details
          vcat [ ppr implicit_tvs, ppr explicit_univ_tvs, ppr req_theta
               , ppr explicit_ex_tvs, ppr prov_theta, ppr sig_body_ty ]
 
-       ; tcCheckPatSynPat lpat
-
        ; (arg_tys, pat_ty) <- case tcSplitFunTysN decl_arity sig_body_ty of
                                  Right stuff  -> return stuff
                                  Left missing -> wrongNumberOfParmsErr name decl_arity missing
@@ -1032,68 +1029,6 @@ Any change to this ordering should make sure to change deSugar/DsExpr.hs if you
 want to avoid difficult to decipher core lint errors!
  -}
 
-tcCheckPatSynPat :: LPat GhcRn -> TcM ()
-tcCheckPatSynPat = go
-  where
-    go :: LPat GhcRn -> TcM ()
-    go = addLocM go1
-
-    go1 :: Pat GhcRn -> TcM ()
-    -- See Note [Bad patterns]
-    go1 p@(AsPat _ _)         = asPatInPatSynErr p
-    go1 p at NPlusKPat{}         = nPlusKPatInPatSynErr p
-
-    go1   (ConPatIn _ info)   = mapM_ go (hsConPatArgs info)
-    go1   VarPat{}            = return ()
-    go1   WildPat{}           = return ()
-    go1   (LazyPat pat)       = go pat
-    go1   (ParPat pat)        = go pat
-    go1   (BangPat pat)       = go pat
-    go1   (PArrPat pats _)    = mapM_ go pats
-    go1   (ListPat pats _ _)  = mapM_ go pats
-    go1   (TuplePat pats _ _) = mapM_ go pats
-    go1   (SumPat pat _ _ _)  = go pat
-    go1   LitPat{}            = return ()
-    go1   NPat{}              = return ()
-    go1   (SigPatIn pat _)    = go pat
-    go1   (ViewPat _ pat _)   = go pat
-    go1   (SplicePat splice)
-      | HsSpliced mod_finalizers (HsSplicedPat pat) <- splice
-                              = do addModFinalizersWithLclEnv mod_finalizers
-                                   go1 pat
-      | otherwise             = panic "non-pattern from spliced thing"
-    go1   ConPatOut{}         = panic "ConPatOut in output of renamer"
-    go1   SigPatOut{}         = panic "SigPatOut in output of renamer"
-    go1   CoPat{}             = panic "CoPat in output of renamer"
-
-asPatInPatSynErr :: (SourceTextX p, OutputableBndrId p) => Pat p -> TcM a
-asPatInPatSynErr pat
-  = failWithTc $
-    hang (text "Pattern synonym definition cannot contain as-patterns (@):")
-       2 (ppr pat)
-
-nPlusKPatInPatSynErr :: (SourceTextX p, OutputableBndrId p) => Pat p -> TcM a
-nPlusKPatInPatSynErr pat
-  = failWithTc $
-    hang (text "Pattern synonym definition cannot contain n+k-pattern:")
-       2 (ppr pat)
-
-{- Note [Bad patterns]
-~~~~~~~~~~~~~~~~~~~~~~
-We don't currently allow as-patterns or n+k patterns in a pattern synonym.
-Reason: consider
-  pattern P x y = x@(Just y)
-
-What would
-  f (P Nothing False) = e
-mean?  Presumably something like
-  f Nothing@(Just False) = e
-But as-patterns don't allow a pattern before the @ sign!  Perhaps they
-should -- with p1 at p2 meaning match both p1 and p2 -- but they don't
-currently.  Hence bannning them in pattern synonyms.  Actually lifting
-the restriction would be simple and well-defined.  See Trac #9793.
--}
-
 
 nonBidirectionalErr :: Outputable name => name -> TcM a
 nonBidirectionalErr name = failWithTc $
diff --git a/docs/users_guide/glasgow_exts.rst b/docs/users_guide/glasgow_exts.rst
index 49c6ed4..1717cbb 100644
--- a/docs/users_guide/glasgow_exts.rst
+++ b/docs/users_guide/glasgow_exts.rst
@@ -5586,6 +5586,24 @@ Matching of pattern synonyms
 
 A pattern synonym occurrence in a pattern is evaluated by first matching
 against the pattern synonym itself, and then on the argument patterns.
+
+More precisely, the semantics of pattern matching is given in
+`Section 3.17 of the Haskell 2010 report <https://www.haskell.org/onlinereport/haskell2010/haskellch3.html#x8-580003.17>`__.   To the informal semantics in Section 3.17.2 we add this extra rule:
+
+* If the pattern is a constructor pattern ``(P p1 ... pn)``, where ``P`` is
+  a pattern synonym defined by ``P x1 ... xn = p`` or ``P x1 ... xn <- p``, then:
+
+  (a) Match the value ``v`` against ``p``. If this match fails or diverges,
+      so does the whole (pattern synonym) match.   Otherwise the match
+      against ``p`` must bind the variables ``x1 ... xn``; let them be bound to values ``v1 ... vn``.
+
+  (b) Match ``v1`` against ``p1``, ``v2`` against ``p2`` and so on.
+      If any of these matches fail or diverge, so does the whole match.
+
+  (c) If all the matches against the ``pi`` succeed, the match succeeds,
+      binding the variables bound by the ``pi`` . (The ``xi`` are not
+      bound; they remain local to the pattern synonym declaration.)
+
 For example, in the following program, ``f`` and ``f'`` are equivalent: ::
 
     pattern Pair x y <- [x, y]
diff --git a/testsuite/tests/patsyn/should_fail/all.T b/testsuite/tests/patsyn/should_fail/all.T
index 0f4c608..d3a0a9b 100644
--- a/testsuite/tests/patsyn/should_fail/all.T
+++ b/testsuite/tests/patsyn/should_fail/all.T
@@ -1,7 +1,7 @@
 test('mono', normal, compile_fail, [''])
 test('unidir', normal, compile_fail, [''])
 test('local', normal, compile_fail, [''])
-test('as-pattern', normal, compile_fail, [''])
+test('as-pattern', normal, compile, [''])
 test('T9161-1', normal, compile_fail, [''])
 test('T9161-2', normal, compile_fail, [''])
 test('T9705-1', normal, compile_fail, [''])
diff --git a/testsuite/tests/patsyn/should_fail/as-pattern.hs b/testsuite/tests/patsyn/should_fail/as-pattern.hs
index 2794bed..f3ec9c9 100644
--- a/testsuite/tests/patsyn/should_fail/as-pattern.hs
+++ b/testsuite/tests/patsyn/should_fail/as-pattern.hs
@@ -1,4 +1,5 @@
 {-# LANGUAGE PatternSynonyms #-}
 module ShouldFail where
 
+-- This is now ok (following GHC proposal #94)
 pattern P x y <- x@(Just y)
diff --git a/testsuite/tests/patsyn/should_fail/as-pattern.stderr b/testsuite/tests/patsyn/should_fail/as-pattern.stderr
deleted file mode 100644
index 61df617..0000000
--- a/testsuite/tests/patsyn/should_fail/as-pattern.stderr
+++ /dev/null
@@ -1,5 +0,0 @@
-
-as-pattern.hs:4:18: error:
-    • Pattern synonym definition cannot contain as-patterns (@):
-        x@(Just y)
-    • In the declaration for pattern synonym ‘P’


From git at git.haskell.org  Thu Mar 22 11:02:01 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Thu, 22 Mar 2018 11:02:01 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4394: Refactored coercionKindsRole (as
 per #11735) (ecc0716)
Message-ID: <20180322110201.4B5183A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/tdammers/D4394
Link       : http://ghc.haskell.org/trac/ghc/changeset/ecc0716b8deca3dd5e28a895f59b9d314456338b/ghc

>---------------------------------------------------------------

commit ecc0716b8deca3dd5e28a895f59b9d314456338b
Author: Tobias Dammers <tdammers at gmail.com>
Date:   Wed Jan 24 17:20:20 2018 +0100

    Refactored coercionKindsRole (as per #11735)


>---------------------------------------------------------------

ecc0716b8deca3dd5e28a895f59b9d314456338b
 compiler/types/Coercion.hs | 74 ++++++++++++++++------------------------------
 1 file changed, 25 insertions(+), 49 deletions(-)

diff --git a/compiler/types/Coercion.hs b/compiler/types/Coercion.hs
index f559a3a..5c9da1b 100644
--- a/compiler/types/Coercion.hs
+++ b/compiler/types/Coercion.hs
@@ -1794,77 +1794,53 @@ coercionKinds tys = sequenceA $ map coercionKind tys
 -- | Get a coercion's kind and role.
 -- Why both at once?  See Note [Computing a coercion kind and role]
 coercionKindRole :: Coercion -> (Pair Type, Role)
-coercionKindRole = go
+coercionKindRole co = (coercionKind co, coercionRole co)
+
+-- | Retrieve the role from a coercion.
+coercionRole :: Coercion -> Role
+coercionRole = go
   where
-    go (Refl r ty) = (Pair ty ty, r)
-    go (TyConAppCo r tc cos)
-      = (mkTyConApp tc <$> (sequenceA $ map coercionKind cos), r)
-    go (AppCo co1 co2)
-      = let (tys1, r1) = go co1 in
-        (mkAppTy <$> tys1 <*> coercionKind co2, r1)
-    go (ForAllCo tv1 k_co co)
-      = let Pair _ k2          = coercionKind k_co
-            tv2                = setTyVarKind tv1 k2
-            (Pair ty1 ty2, r)  = go co
-            subst = zipTvSubst [tv1] [TyVarTy tv2 `mkCastTy` mkSymCo k_co]
-            ty2' = substTyAddInScope subst ty2 in
-            -- We need free vars of ty2 in scope to satisfy the invariant
-            -- from Note [The substitution invariant]
-            -- This is doing repeated substitutions and probably doesn't
-            -- need to, see #11735
-        (mkInvForAllTy <$> Pair tv1 tv2 <*> Pair ty1 ty2', r)
-    go (FunCo r co1 co2)
-      = (mkFunTy <$> coercionKind co1 <*> coercionKind co2, r)
+    go (Refl r _) = r
+    go (TyConAppCo r _ _) = r
+    go (AppCo co1 _) = go co1
+    go (ForAllCo _ _ co) = go co
+    go (FunCo r _ _) = r
     go (CoVarCo cv) = go_var cv
     go (HoleCo h)   = go_var (coHoleCoVar h)
-    go co@(AxiomInstCo ax _ _) = (coercionKind co, coAxiomRole ax)
-    go (UnivCo _ r ty1 ty2)  = (Pair ty1 ty2, r)
-    go (SymCo co) = first swap $ go co
-    go (TransCo co1 co2)
-      = let (tys1, r) = go co1 in
-        (Pair (pFst tys1) (pSnd $ coercionKind co2), r)
+    go (AxiomInstCo ax _ _) = coAxiomRole ax
+    go (UnivCo _ r _ _)  = r
+    go (SymCo co) = go co
+    go (TransCo co1 co2) = go co1
     go (NthCo d co)
       | Just (tv1, _) <- splitForAllTy_maybe ty1
       = ASSERT( d == 0 )
-        let (tv2, _) = splitForAllTy ty2 in
-        (tyVarKind <$> Pair tv1 tv2, Nominal)
+        Nominal
 
       | otherwise
       = let (tc1,  args1) = splitTyConApp ty1
             (_tc2, args2) = splitTyConApp ty2
         in
         ASSERT2( tc1 == _tc2, ppr d $$ ppr tc1 $$ ppr _tc2 )
-        ((`getNth` d) <$> Pair args1 args2, nthRole r tc1 d)
+        (nthRole r tc1 d)
 
       where
-        (Pair ty1 ty2, r) = go co
-    go co@(LRCo {}) = (coercionKind co, Nominal)
+        (Pair ty1 ty2, r) = coercionKindRole co
+    go (LRCo {}) = Nominal
     go (InstCo co arg) = go_app co [arg]
-    go (CoherenceCo co1 co2)
-      = let (Pair t1 t2, r) = go co1 in
-        (Pair (t1 `mkCastTy` co2) t2, r)
-    go co@(KindCo {}) = (coercionKind co, Nominal)
-    go (SubCo co) = (coercionKind co, Representational)
-    go co@(AxiomRuleCo ax _) = (coercionKind co, coaxrRole ax)
+    go (CoherenceCo co1 _) = go co1
+    go (KindCo {}) = Nominal
+    go (SubCo _) = Representational
+    go (AxiomRuleCo ax _) = coaxrRole ax
 
     -------------
-    go_var cv = (coVarTypes cv, coVarRole cv)
+    go_var = coVarRole
 
     -------------
-    go_app :: Coercion -> [Coercion] -> (Pair Type, Role)
+    go_app :: Coercion -> [Coercion] -> Role
     -- Collect up all the arguments and apply all at once
     -- See Note [Nested InstCos]
     go_app (InstCo co arg) args = go_app co (arg:args)
-    go_app co              args
-      = let (pair, r) = go co in
-        (piResultTys <$> pair <*> (sequenceA $ map coercionKind args), r)
-
--- | Retrieve the role from a coercion.
-coercionRole :: Coercion -> Role
-coercionRole = snd . coercionKindRole
-  -- There's not a better way to do this, because NthCo needs the *kind*
-  -- and role of its argument. Luckily, laziness should generally avoid
-  -- the need for computing kinds in other cases.
+    go_app co              args = go co
 
 {-
 Note [Nested InstCos]


From git at git.haskell.org  Thu Mar 22 11:02:04 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Thu, 22 Mar 2018 11:02:04 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4394: Added SCCs to hunt down #14683
 (38ee99b)
Message-ID: <20180322110204.285423A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/tdammers/D4394
Link       : http://ghc.haskell.org/trac/ghc/changeset/38ee99b16a728c0d48b6993737690b9acacb20fc/ghc

>---------------------------------------------------------------

commit 38ee99b16a728c0d48b6993737690b9acacb20fc
Author: Tobias Dammers <tdammers at gmail.com>
Date:   Wed Jan 24 16:07:00 2018 +0100

    Added SCCs to hunt down #14683


>---------------------------------------------------------------

38ee99b16a728c0d48b6993737690b9acacb20fc
 compiler/simplCore/Simplify.hs | 79 +++++++++++++++++++++++++-----------------
 compiler/types/TyCoRep.hs      |  9 ++---
 2 files changed, 53 insertions(+), 35 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc 38ee99b16a728c0d48b6993737690b9acacb20fc

From git at git.haskell.org  Thu Mar 22 11:02:06 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Thu, 22 Mar 2018 11:02:06 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4394: Applying patch suggested in #11735
 to improve coercionKind perf (a38a2b8)
Message-ID: <20180322110206.E80513A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/tdammers/D4394
Link       : http://ghc.haskell.org/trac/ghc/changeset/a38a2b855d00ea46fb75efd247da4a6f091cbabb/ghc

>---------------------------------------------------------------

commit a38a2b855d00ea46fb75efd247da4a6f091cbabb
Author: Tobias Dammers <tdammers at gmail.com>
Date:   Wed Jan 24 16:05:55 2018 +0100

    Applying patch suggested in #11735 to improve coercionKind perf


>---------------------------------------------------------------

a38a2b855d00ea46fb75efd247da4a6f091cbabb
 compiler/types/Coercion.hs | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/compiler/types/Coercion.hs b/compiler/types/Coercion.hs
index 7a7918c..f559a3a 100644
--- a/compiler/types/Coercion.hs
+++ b/compiler/types/Coercion.hs
@@ -1784,6 +1784,8 @@ substitute for them all at once.  Remarkably, for Trac #11735 this single
 change reduces /total/ compile time by a factor of more than ten.
 
 -}
+=======
+>>>>>>> Applying patch suggested in #11735 to improve coercionKind perf
 
 -- | Apply 'coercionKind' to multiple 'Coercion's
 coercionKinds :: [Coercion] -> Pair [Type]


From git at git.haskell.org  Thu Mar 22 11:02:09 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Thu, 22 Mar 2018 11:02:09 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4394: Caching coercion roles in NthCo
 (#11735) (4c94815)
Message-ID: <20180322110209.C0ED23A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/tdammers/D4394
Link       : http://ghc.haskell.org/trac/ghc/changeset/4c94815b4677ede2d7c9ca990eb728ee695d205c/ghc

>---------------------------------------------------------------

commit 4c94815b4677ede2d7c9ca990eb728ee695d205c
Author: Tobias Dammers <tdammers at gmail.com>
Date:   Thu Jan 25 20:33:58 2018 +0100

    Caching coercion roles in NthCo (#11735)


>---------------------------------------------------------------

4c94815b4677ede2d7c9ca990eb728ee695d205c
 compiler/coreSyn/CoreFVs.hs      |  2 +-
 compiler/coreSyn/CoreLint.hs     |  2 +-
 compiler/iface/TcIface.hs        |  2 +-
 compiler/iface/ToIface.hs        |  2 +-
 compiler/typecheck/TcTyDecls.hs  |  2 +-
 compiler/typecheck/TcType.hs     |  2 +-
 compiler/typecheck/TcUnify.hs    |  2 +-
 compiler/typecheck/TcValidity.hs |  2 +-
 compiler/types/Coercion.hs       | 45 ++++++++++++++++++++++------------------
 compiler/types/FamInstEnv.hs     |  2 +-
 compiler/types/OptCoercion.hs    |  4 ++--
 compiler/types/TyCoRep.hs        | 36 +++++++++++++++++++++++++-------
 compiler/types/Type.hs           |  8 +++----
 13 files changed, 68 insertions(+), 43 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc 4c94815b4677ede2d7c9ca990eb728ee695d205c

From git at git.haskell.org  Thu Mar 22 11:02:15 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Thu, 22 Mar 2018 11:02:15 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4394: Make mkNthCo take a Role parameter.
 (b2b5d3a)
Message-ID: <20180322110215.655A23A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/tdammers/D4394
Link       : http://ghc.haskell.org/trac/ghc/changeset/b2b5d3ade22bcf33c18490e8dcf03c1dc3e5061d/ghc

>---------------------------------------------------------------

commit b2b5d3ade22bcf33c18490e8dcf03c1dc3e5061d
Author: Richard Eisenberg <rae at cs.brynmawr.edu>
Date:   Fri Jan 26 22:09:33 2018 -0500

    Make mkNthCo take a Role parameter.
    
    Most callers of mkNthCo know the role of the coercion they
    are trying to make. So instead of calculating this role, just
    pass it in.


>---------------------------------------------------------------

b2b5d3ade22bcf33c18490e8dcf03c1dc3e5061d
 compiler/coreSyn/CoreLint.hs      |  11 ++-
 compiler/coreSyn/CoreOpt.hs       |  24 +++----
 compiler/coreSyn/CoreUtils.hs     |   4 +-
 compiler/iface/TcIface.hs         |   2 +-
 compiler/typecheck/TcCanonical.hs |   2 +-
 compiler/typecheck/TcEvidence.hs  |  11 +--
 compiler/typecheck/TcUnify.hs     |   4 +-
 compiler/types/Coercion.hs        | 139 ++++++++++++++++++++------------------
 compiler/types/Coercion.hs-boot   |   2 +-
 compiler/types/OptCoercion.hs     | 109 +++++++++++++-----------------
 compiler/types/TyCoRep.hs         |  11 ++-
 compiler/types/Type.hs            |   6 +-
 compiler/types/Unify.hs           |   4 +-
 13 files changed, 163 insertions(+), 166 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc b2b5d3ade22bcf33c18490e8dcf03c1dc3e5061d

From git at git.haskell.org  Thu Mar 22 11:02:12 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Thu, 22 Mar 2018 11:02:12 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4394: Simplification as per #11735
 (28ff8db)
Message-ID: <20180322110212.8AE363A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/tdammers/D4394
Link       : http://ghc.haskell.org/trac/ghc/changeset/28ff8db516843a073c0554047dd47f8dabf66ff2/ghc

>---------------------------------------------------------------

commit 28ff8db516843a073c0554047dd47f8dabf66ff2
Author: Tobias Dammers <tdammers at gmail.com>
Date:   Thu Jan 25 11:16:30 2018 +0100

    Simplification as per #11735
    
    (https://ghc.haskell.org/trac/ghc/ticket/11735#comment:19)


>---------------------------------------------------------------

28ff8db516843a073c0554047dd47f8dabf66ff2
 compiler/types/Coercion.hs | 10 ++++------
 1 file changed, 4 insertions(+), 6 deletions(-)

diff --git a/compiler/types/Coercion.hs b/compiler/types/Coercion.hs
index 5c9da1b..56341d0 100644
--- a/compiler/types/Coercion.hs
+++ b/compiler/types/Coercion.hs
@@ -1826,7 +1826,7 @@ coercionRole = go
       where
         (Pair ty1 ty2, r) = coercionKindRole co
     go (LRCo {}) = Nominal
-    go (InstCo co arg) = go_app co [arg]
+    go (InstCo co arg) = go_app co
     go (CoherenceCo co1 _) = go co1
     go (KindCo {}) = Nominal
     go (SubCo _) = Representational
@@ -1836,11 +1836,9 @@ coercionRole = go
     go_var = coVarRole
 
     -------------
-    go_app :: Coercion -> [Coercion] -> Role
-    -- Collect up all the arguments and apply all at once
-    -- See Note [Nested InstCos]
-    go_app (InstCo co arg) args = go_app co (arg:args)
-    go_app co              args = go co
+    go_app :: Coercion -> Role
+    go_app (InstCo co arg) = go_app co
+    go_app co              = go co
 
 {-
 Note [Nested InstCos]


From git at git.haskell.org  Thu Mar 22 11:02:18 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Thu, 22 Mar 2018 11:02:18 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4394: Fixed unused variables (fe5a03c)
Message-ID: <20180322110218.2C1583A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/tdammers/D4394
Link       : http://ghc.haskell.org/trac/ghc/changeset/fe5a03c1c02131aa2c790f1f0b2a6c14fe96fd3b/ghc

>---------------------------------------------------------------

commit fe5a03c1c02131aa2c790f1f0b2a6c14fe96fd3b
Author: Tobias Dammers <tdammers at gmail.com>
Date:   Mon Mar 5 15:18:41 2018 +0100

    Fixed unused variables


>---------------------------------------------------------------

fe5a03c1c02131aa2c790f1f0b2a6c14fe96fd3b
 compiler/types/Coercion.hs | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/compiler/types/Coercion.hs b/compiler/types/Coercion.hs
index 8550e85..1e529f7 100644
--- a/compiler/types/Coercion.hs
+++ b/compiler/types/Coercion.hs
@@ -826,8 +826,8 @@ mkNthCo r n co
     good_call
       -- If the Coercion passed in is between forall-types, then the Int must
       -- be 0 and the role must be Nominal.
-      | Just (tv1, _) <- splitForAllTy_maybe ty1
-      , Just (tv2, _) <- splitForAllTy_maybe ty2
+      | Just (_tv1, _) <- splitForAllTy_maybe ty1
+      , Just (_tv2, _) <- splitForAllTy_maybe ty2
       = n == 0 && r == Nominal
 
       -- If the Coercion passed in is between T tys and T tys', then the Int
@@ -1288,12 +1288,12 @@ mkCoCast c g
        -- g1 :: s1 ~# s2
        -- g2 :: t1 ~# t2
     (tc, _) = splitTyConApp (pFst $ coercionKind g)
-    (n_args, role)
-      | tc `hasKey` eqPrimTyConKey     = (4, Nominal)
-      | tc `hasKey` eqReprPrimTyConKey = (4, Representational)
-      | tc `hasKey` eqTyConKey         = (3, Nominal)
-      | tc `hasKey` heqTyConKey        = (4, Nominal)
-      | tc `hasKey` coercibleTyConKey  = (3, Representational)
+    n_args
+      | tc `hasKey` eqPrimTyConKey     = 4
+      | tc `hasKey` eqReprPrimTyConKey = 4
+      | tc `hasKey` eqTyConKey         = 3
+      | tc `hasKey` heqTyConKey        = 4
+      | tc `hasKey` coercibleTyConKey  = 3
       | otherwise                      = pprPanic "mkCoCast" (ppr g $$ ppr (coercionKind g))
     co_list = decomposeCo (tyConArity tc) g (tyConRolesRepresentational tc)
     g1 = co_list `getNth` (n_args - 2)


From git at git.haskell.org  Thu Mar 22 11:02:20 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Thu, 22 Mar 2018 11:02:20 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4394: Documented invariant on cached
 roles (766ae47)
Message-ID: <20180322110220.E6DF13A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/tdammers/D4394
Link       : http://ghc.haskell.org/trac/ghc/changeset/766ae4795c15ea70f3445c88de56a6ce9fa7c6ae/ghc

>---------------------------------------------------------------

commit 766ae4795c15ea70f3445c88de56a6ce9fa7c6ae
Author: Tobias Dammers <tdammers at gmail.com>
Date:   Wed Feb 7 13:45:01 2018 +0100

    Documented invariant on cached roles


>---------------------------------------------------------------

766ae4795c15ea70f3445c88de56a6ce9fa7c6ae
 compiler/types/TyCoRep.hs | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/compiler/types/TyCoRep.hs b/compiler/types/TyCoRep.hs
index b6ccc93..c32bdb6 100644
--- a/compiler/types/TyCoRep.hs
+++ b/compiler/types/TyCoRep.hs
@@ -857,7 +857,11 @@ data Coercion
     -- :: "e" _ -> e0 -> e (inverse of TyConAppCo, see Note [TyConAppCo roles])
     -- Using NthCo on a ForAllCo gives an N coercion always
     -- See Note [NthCo and newtypes]
+    --
+    -- Invariant:  (NthCo r i co), it is always the case that r = role of (Nth i co)
+    -- That is: the role of the entire coercion is redundantly cached here.
     -- See Note [NthCo Cached Roles]
+    --
     -- The Role might be more permissive than otherwise possible. That is, even
     -- if the Coercion inside is Nominal, the role could be Representational
     -- (it's like using a SubCo)


From git at git.haskell.org  Thu Mar 22 11:02:23 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Thu, 22 Mar 2018 11:02:23 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4394: Tighten cached role in NthCo
 (c678314)
Message-ID: <20180322110223.BA3373A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/tdammers/D4394
Link       : http://ghc.haskell.org/trac/ghc/changeset/c67831495fe7d728e789632dc161bddd29e5fd9d/ghc

>---------------------------------------------------------------

commit c67831495fe7d728e789632dc161bddd29e5fd9d
Author: Richard Eisenberg <rae at cs.brynmawr.edu>
Date:   Mon Feb 12 13:02:23 2018 -0500

    Tighten cached role in NthCo


>---------------------------------------------------------------

c67831495fe7d728e789632dc161bddd29e5fd9d
 compiler/coreSyn/CoreLint.hs     |   9 +--
 compiler/coreSyn/CoreUtils.hs    |   2 +-
 compiler/iface/TcIface.hs        |   3 +-
 compiler/iface/ToIface.hs        |   2 +-
 compiler/typecheck/TcEvidence.hs |   3 +-
 compiler/types/Coercion.hs       | 168 ++++++++++++++++++++++-----------------
 compiler/types/Coercion.hs-boot  |   2 +-
 compiler/types/OptCoercion.hs    |  20 ++---
 compiler/types/TyCoRep.hs        |   6 +-
 docs/core-spec/CoreLint.ott      |   5 +-
 10 files changed, 115 insertions(+), 105 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc c67831495fe7d728e789632dc161bddd29e5fd9d

From git at git.haskell.org  Thu Mar 22 11:02:34 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Thu, 22 Mar 2018 11:02:34 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4394: Fix test to reflect changed NthCo
 ctor (1af89d5)
Message-ID: <20180322110234.D47EE3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/tdammers/D4394
Link       : http://ghc.haskell.org/trac/ghc/changeset/1af89d545b8a605a6d2c6036fde1a20b147b294f/ghc

>---------------------------------------------------------------

commit 1af89d545b8a605a6d2c6036fde1a20b147b294f
Author: Tobias Dammers <tdammers at gmail.com>
Date:   Tue Mar 13 13:59:36 2018 +0100

    Fix test to reflect changed NthCo ctor


>---------------------------------------------------------------

1af89d545b8a605a6d2c6036fde1a20b147b294f
 testsuite/tests/pmcheck/should_compile/T11195.hs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/testsuite/tests/pmcheck/should_compile/T11195.hs b/testsuite/tests/pmcheck/should_compile/T11195.hs
index 236932e..0c35b4f 100644
--- a/testsuite/tests/pmcheck/should_compile/T11195.hs
+++ b/testsuite/tests/pmcheck/should_compile/T11195.hs
@@ -62,7 +62,7 @@ opt_transList :: InScopeSet -> [NormalCo] -> [NormalCo] -> [NormalCo]
 opt_transList is = zipWith (opt_trans is)
 
 opt_trans_rule :: InScopeSet -> NormalNonIdCo -> NormalNonIdCo -> Maybe NormalCo
-opt_trans_rule is in_co1@(NthCo d1 co1) in_co2@(NthCo d2 co2)
+opt_trans_rule is in_co1@(NthCo r1 d1 co1) in_co2@(NthCo r2 d2 co2)
   | d1 == d2
   , co1 `compatible_co` co2 = undefined
 


From git at git.haskell.org  Thu Mar 22 11:02:29 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Thu, 22 Mar 2018 11:02:29 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4394: Refactored setNominalRole_maybe to
 avoid dragging role through recursion (0869056)
Message-ID: <20180322110229.4A9283A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/tdammers/D4394
Link       : http://ghc.haskell.org/trac/ghc/changeset/08690568f1285b0fce694589d411998b3c37f3ed/ghc

>---------------------------------------------------------------

commit 08690568f1285b0fce694589d411998b3c37f3ed
Author: Tobias Dammers <tdammers at gmail.com>
Date:   Mon Mar 5 12:34:30 2018 +0100

    Refactored setNominalRole_maybe to avoid dragging role through recursion


>---------------------------------------------------------------

08690568f1285b0fce694589d411998b3c37f3ed
 compiler/types/Coercion.hs | 66 ++++++++++++++++++++++++----------------------
 1 file changed, 35 insertions(+), 31 deletions(-)

diff --git a/compiler/types/Coercion.hs b/compiler/types/Coercion.hs
index fbb8de9..dd4d055 100644
--- a/compiler/types/Coercion.hs
+++ b/compiler/types/Coercion.hs
@@ -1054,37 +1054,41 @@ setNominalRole_maybe :: Role -- of input coercion
                      -> Coercion -> Maybe Coercion
 setNominalRole_maybe r co
   | r == Nominal = Just co
-setNominalRole_maybe _ (SubCo co)  = Just co
-setNominalRole_maybe _ (Refl _ ty) = Just $ Refl Nominal ty
-setNominalRole_maybe _ (TyConAppCo Representational tc cos)
-  = do { cos' <- zipWithM setNominalRole_maybe (tyConRolesX Representational tc) cos
-       ; return $ TyConAppCo Nominal tc cos' }
-setNominalRole_maybe _ (FunCo Representational co1 co2)
-  = do { co1' <- setNominalRole_maybe Representational co1
-       ; co2' <- setNominalRole_maybe Representational co2
-       ; return $ FunCo Nominal co1' co2'
-       }
-setNominalRole_maybe r (SymCo co)
-  = SymCo <$> setNominalRole_maybe r co
-setNominalRole_maybe r (TransCo co1 co2)
-  = TransCo <$> setNominalRole_maybe r co1 <*> setNominalRole_maybe r co2
-setNominalRole_maybe r (AppCo co1 co2)
-  = AppCo <$> setNominalRole_maybe r co1 <*> pure co2
-setNominalRole_maybe r (ForAllCo tv kind_co co)
-  = ForAllCo tv kind_co <$> setNominalRole_maybe r co
-setNominalRole_maybe _ (NthCo _r n co)
-  = NthCo Nominal n <$> setNominalRole_maybe (coercionRole co) co
-setNominalRole_maybe r (InstCo co arg)
-  = InstCo <$> setNominalRole_maybe r co <*> pure arg
-setNominalRole_maybe r (CoherenceCo co1 co2)
-  = CoherenceCo <$> setNominalRole_maybe r co1 <*> pure co2
-setNominalRole_maybe _ (UnivCo prov _ co1 co2)
-  | case prov of UnsafeCoerceProv -> True   -- it's always unsafe
-                 PhantomProv _    -> False  -- should always be phantom
-                 ProofIrrelProv _ -> True   -- it's always safe
-                 PluginProv _     -> False  -- who knows? This choice is conservative.
-  = Just $ UnivCo prov Nominal co1 co2
-setNominalRole_maybe _ _ = Nothing
+  | otherwise = setNominalRole_maybe_helper co
+  where
+    setNominalRole_maybe_helper (SubCo co)  = Just co
+    setNominalRole_maybe_helper (Refl _ ty) = Just $ Refl Nominal ty
+    setNominalRole_maybe_helper (TyConAppCo Representational tc cos)
+      = do { cos' <- zipWithM setNominalRole_maybe (tyConRolesX Representational tc) cos
+           ; return $ TyConAppCo Nominal tc cos' }
+    setNominalRole_maybe_helper (FunCo Representational co1 co2)
+      = do { co1' <- setNominalRole_maybe Representational co1
+           ; co2' <- setNominalRole_maybe Representational co2
+           ; return $ FunCo Nominal co1' co2'
+           }
+    setNominalRole_maybe_helper (SymCo co)
+      = SymCo <$> setNominalRole_maybe_helper co
+    setNominalRole_maybe_helper (TransCo co1 co2)
+      = TransCo <$> setNominalRole_maybe_helper co1 <*> setNominalRole_maybe_helper co2
+    setNominalRole_maybe_helper (AppCo co1 co2)
+      = AppCo <$> setNominalRole_maybe_helper co1 <*> pure co2
+    setNominalRole_maybe_helper (ForAllCo tv kind_co co)
+      = ForAllCo tv kind_co <$> setNominalRole_maybe_helper co
+    setNominalRole_maybe_helper (NthCo _r n co)
+      -- NB, this case recurses via setNominalRole_maybe, not
+      -- setNominalRole_maybe_helper!
+      = NthCo Nominal n <$> setNominalRole_maybe (coercionRole co) co
+    setNominalRole_maybe_helper (InstCo co arg)
+      = InstCo <$> setNominalRole_maybe_helper co <*> pure arg
+    setNominalRole_maybe_helper (CoherenceCo co1 co2)
+      = CoherenceCo <$> setNominalRole_maybe_helper co1 <*> pure co2
+    setNominalRole_maybe_helper (UnivCo prov _ co1 co2)
+      | case prov of UnsafeCoerceProv -> True   -- it's always unsafe
+                     PhantomProv _    -> False  -- should always be phantom
+                     ProofIrrelProv _ -> True   -- it's always safe
+                     PluginProv _     -> False  -- who knows? This choice is conservative.
+      = Just $ UnivCo prov Nominal co1 co2
+    setNominalRole_maybe_helper _ = Nothing
 
 -- | Make a phantom coercion between two types. The coercion passed
 -- in must be a nominal coercion between the kinds of the


From git at git.haskell.org  Thu Mar 22 11:02:32 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Thu, 22 Mar 2018 11:02:32 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4394: Fixes to Coercion.hs (4fa4034)
Message-ID: <20180322110232.1BD493A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/tdammers/D4394
Link       : http://ghc.haskell.org/trac/ghc/changeset/4fa4034bdf1b7ef1444602bef6499e14ab5b58b9/ghc

>---------------------------------------------------------------

commit 4fa4034bdf1b7ef1444602bef6499e14ab5b58b9
Author: Tobias Dammers <tdammers at gmail.com>
Date:   Mon Mar 5 11:20:34 2018 +0100

    Fixes to Coercion.hs


>---------------------------------------------------------------

4fa4034bdf1b7ef1444602bef6499e14ab5b58b9
 compiler/types/Coercion.hs | 19 ++++++++++---------
 1 file changed, 10 insertions(+), 9 deletions(-)

diff --git a/compiler/types/Coercion.hs b/compiler/types/Coercion.hs
index a1368de..af3cb2c 100644
--- a/compiler/types/Coercion.hs
+++ b/compiler/types/Coercion.hs
@@ -815,16 +815,17 @@ mkTransCo co1 co2       = TransCo co1 co2
 mkNthCo :: HasDebugCallStack
         => Role  -- the role of the coercion you're creating
         -> Int
-				-> Coercion
-				-> Coercion
+        -> Coercion
+        -> Coercion
 mkNthCo r n co
   = ASSERT(good_call)
     go r n co
   where
-		(ty1, ty2) = coercionKind co
+    Pair ty1 ty2 = coercionKind co
+
     good_call
-		  -- If the Coercion passed in is between forall-types, then the Int must
-		  -- be 0 and the role must be Nominal.
+      -- If the Coercion passed in is between forall-types, then the Int must
+      -- be 0 and the role must be Nominal.
       | Just (tv1, _) <- splitForAllTy_maybe ty1
       , Just (tv2, _) <- splitForAllTy_maybe ty2
       = n == 0 && r == Nominal
@@ -841,8 +842,8 @@ mkNthCo r n co
       -- See also Note [NthCo Cached Roles] if you're wondering why it's
       -- blaringly obvious that we should be *computing* this role instead of
       -- passing it in.
-      | Just (tc1, tys1) <- splitTyConnApp_maybe ty1
-      , Just (tc2, tys1) <- splitForAllTy_maybe ty2
+      | Just (tc1, tys1) <- splitTyConApp_maybe ty1
+      , Just (tc2, tys2) <- splitTyConApp_maybe ty2
       , tc1 == tc2
       = let len1 = length tys1
             len2 = length tys2
@@ -853,7 +854,7 @@ mkNthCo r n co
         in len1 == len2 && n < len1 && good_role
 
       | otherwise
-			= True
+      = True
 
     go r 0 (Refl _ ty)
       | Just (tv, _) <- splitForAllTy_maybe ty
@@ -905,7 +906,7 @@ mkNthCo r n co
                                                             , ppr r ]) )
                                              arg_cos `getNth` n
 
-    mkNthCo r n co =
+    go r n co =
       NthCo r n co
 
 -- | If you're about to call @mkNthCo r n co@, then @r@ should be


From git at git.haskell.org  Thu Mar 22 11:02:26 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Thu, 22 Mar 2018 11:02:26 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4394: NthCo handling,
 assertions and documentation improvements (8e673eb)
Message-ID: <20180322110226.832073A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/tdammers/D4394
Link       : http://ghc.haskell.org/trac/ghc/changeset/8e673eb99f6b1ae9edff09bc9f8651dbd9917a5c/ghc

>---------------------------------------------------------------

commit 8e673eb99f6b1ae9edff09bc9f8651dbd9917a5c
Author: Tobias Dammers <tdammers at gmail.com>
Date:   Sun Mar 4 21:07:13 2018 +0100

    NthCo handling, assertions and documentation improvements


>---------------------------------------------------------------

8e673eb99f6b1ae9edff09bc9f8651dbd9917a5c
 compiler/types/Coercion.hs | 160 +++++++++++++++++++++++++++------------------
 1 file changed, 95 insertions(+), 65 deletions(-)

diff --git a/compiler/types/Coercion.hs b/compiler/types/Coercion.hs
index 31db1d3..a1368de 100644
--- a/compiler/types/Coercion.hs
+++ b/compiler/types/Coercion.hs
@@ -230,7 +230,8 @@ where co_rep1, co_rep2 are the coercions on the representations.
 -- > decomposeCo 3 c [r1, r2, r3] = [nth r1 0 c, nth r2 1 c, nth r3 2 c]
 decomposeCo :: Arity -> Coercion
             -> [Role]  -- the roles of the output coercions
-                       -- this must have at least as many entries as the Arity provided
+                       -- this must have at least as many
+                       -- entries as the Arity provided
             -> [Coercion]
 decomposeCo arity co rs
   = [mkNthCo r n co | (n,r) <- [0..(arity-1)] `zip` rs ]
@@ -813,70 +814,99 @@ mkTransCo co1 co2       = TransCo co1 co2
 
 mkNthCo :: HasDebugCallStack
         => Role  -- the role of the coercion you're creating
-        -> Int -> Coercion -> Coercion
--- If the Coercion passed in is between forall-types, then the Int must
--- be 0 and the role must be Nominal. If the Coercion passed in is between
--- T tys and T tys', then the Int must be less than the length of tys/tys'
--- (which must be the same lengths). If the role of the Coercion is
--- nominal, then the role passed in must be nominal. If the role of the
--- Coercion is representational, then the role passed in must be
--- tyConRolesRepresentational T !! n. If the role of the Coercion
--- is Phantom, then the role passed in must be Phantom.
--- See also Note [NthCo Cached Roles] if you're wondering why it's
--- blaringly obvious that we should be *computing* this role instead
--- of passing it in.
-mkNthCo r 0 (Refl _ ty)
-  | Just (tv, _) <- splitForAllTy_maybe ty
-  = ASSERT( r == Nominal )
-    Refl r (tyVarKind tv)
-mkNthCo r n (Refl r0 ty)
-  = ASSERT2( ok_tc_app ty n, ppr n $$ ppr ty )
-    ASSERT( nthRole r0 tc n == r )
-    mkReflCo r (tyConAppArgN n ty)
-  where tc = tyConAppTyCon ty
-
-        ok_tc_app :: Type -> Int -> Bool
-        ok_tc_app ty n
-          | Just (_, tys) <- splitTyConApp_maybe ty
-          = tys `lengthExceeds` n
-          | isForAllTy ty  -- nth:0 pulls out a kind coercion from a hetero forall
-          = n == 0
-          | otherwise
-          = False
-
-mkNthCo r 0 (ForAllCo _ kind_co _)
-  = ASSERT( r == Nominal )
-    kind_co
-  -- If co :: (forall a1:k1. t1) ~ (forall a2:k2. t2)
-  -- then (nth 0 co :: k1 ~N k2)
-
-mkNthCo r n co@(FunCo r0 arg res)
-  -- See Note [Function coercions]
-  -- If FunCo _ arg_co res_co ::   (s1:TYPE sk1 -> s2:TYPE sk2)
-  --                             ~ (t1:TYPE tk1 -> t2:TYPE tk2)
-  -- Then we want to behave as if co was
-  --    TyConAppCo argk_co resk_co arg_co res_co
-  -- where
-  --    argk_co :: sk1 ~ tk1  =  mkNthCo 0 (mkKindCo arg_co)
-  --    resk_co :: sk2 ~ tk2  =  mkNthCo 0 (mkKindCo res_co)
-  --                             i.e. mkRuntimeRepCo
-  = case n of
-      0 -> ASSERT( r == Nominal ) mkRuntimeRepCo arg
-      1 -> ASSERT( r == Nominal ) mkRuntimeRepCo res
-      2 -> ASSERT( r == r0 )      arg
-      3 -> ASSERT( r == r0 )      res
-      _ -> pprPanic "mkNthCo(FunCo)" (ppr n $$ ppr co)
-
-mkNthCo r n (TyConAppCo r0 tc arg_cos) = ASSERT2( r == nthRole r0 tc n
-                                                , (vcat [ ppr tc
-                                                        , ppr arg_cos
-                                                        , ppr r0
-                                                        , ppr n
-                                                        , ppr r ]) )
-                                         arg_cos `getNth` n
-
-mkNthCo r n co =
-  NthCo r n co
+        -> Int
+				-> Coercion
+				-> Coercion
+mkNthCo r n co
+  = ASSERT(good_call)
+    go r n co
+  where
+		(ty1, ty2) = coercionKind co
+    good_call
+		  -- If the Coercion passed in is between forall-types, then the Int must
+		  -- be 0 and the role must be Nominal.
+      | Just (tv1, _) <- splitForAllTy_maybe ty1
+      , Just (tv2, _) <- splitForAllTy_maybe ty2
+      = n == 0 && r == Nominal
+
+      -- If the Coercion passed in is between T tys and T tys', then the Int
+      -- must be less than the length of tys/tys' (which must be the same
+      -- lengths).
+      --
+      -- If the role of the Coercion is nominal, then the role passed in must
+      -- be nominal. If the role of the Coercion is representational, then the
+      -- role passed in must be tyConRolesRepresentational T !! n. If the role
+      -- of the Coercion is Phantom, then the role passed in must be Phantom.
+      --
+      -- See also Note [NthCo Cached Roles] if you're wondering why it's
+      -- blaringly obvious that we should be *computing* this role instead of
+      -- passing it in.
+      | Just (tc1, tys1) <- splitTyConnApp_maybe ty1
+      , Just (tc2, tys1) <- splitForAllTy_maybe ty2
+      , tc1 == tc2
+      = let len1 = length tys1
+            len2 = length tys2
+            good_role = case coercionRole co of
+                          Nominal -> r == Nominal
+                          Representational -> r == (tyConRolesRepresentational tc1 !! n)
+                          Phantom -> r == Phantom
+        in len1 == len2 && n < len1 && good_role
+
+      | otherwise
+			= True
+
+    go r 0 (Refl _ ty)
+      | Just (tv, _) <- splitForAllTy_maybe ty
+      = ASSERT( r == Nominal )
+        Refl r (tyVarKind tv)
+    go r n (Refl r0 ty)
+      = ASSERT2( ok_tc_app ty n, ppr n $$ ppr ty )
+        ASSERT( nthRole r0 tc n == r )
+        mkReflCo r (tyConAppArgN n ty)
+      where tc = tyConAppTyCon ty
+
+            ok_tc_app :: Type -> Int -> Bool
+            ok_tc_app ty n
+              | Just (_, tys) <- splitTyConApp_maybe ty
+              = tys `lengthExceeds` n
+              | isForAllTy ty  -- nth:0 pulls out a kind coercion from a hetero forall
+              = n == 0
+              | otherwise
+              = False
+
+    go r 0 (ForAllCo _ kind_co _)
+      = ASSERT( r == Nominal )
+        kind_co
+      -- If co :: (forall a1:k1. t1) ~ (forall a2:k2. t2)
+      -- then (nth 0 co :: k1 ~N k2)
+
+    go r n co@(FunCo r0 arg res)
+      -- See Note [Function coercions]
+      -- If FunCo _ arg_co res_co ::   (s1:TYPE sk1 -> s2:TYPE sk2)
+      --                             ~ (t1:TYPE tk1 -> t2:TYPE tk2)
+      -- Then we want to behave as if co was
+      --    TyConAppCo argk_co resk_co arg_co res_co
+      -- where
+      --    argk_co :: sk1 ~ tk1  =  mkNthCo 0 (mkKindCo arg_co)
+      --    resk_co :: sk2 ~ tk2  =  mkNthCo 0 (mkKindCo res_co)
+      --                             i.e. mkRuntimeRepCo
+      = case n of
+          0 -> ASSERT( r == Nominal ) mkRuntimeRepCo arg
+          1 -> ASSERT( r == Nominal ) mkRuntimeRepCo res
+          2 -> ASSERT( r == r0 )      arg
+          3 -> ASSERT( r == r0 )      res
+          _ -> pprPanic "mkNthCo(FunCo)" (ppr n $$ ppr co)
+
+    go r n (TyConAppCo r0 tc arg_cos) = ASSERT2( r == nthRole r0 tc n
+                                                    , (vcat [ ppr tc
+                                                            , ppr arg_cos
+                                                            , ppr r0
+                                                            , ppr n
+                                                            , ppr r ]) )
+                                             arg_cos `getNth` n
+
+    mkNthCo r n co =
+      NthCo r n co
 
 -- | If you're about to call @mkNthCo r n co@, then @r@ should be
 -- whatever @nthCoRole n co@ returns.


From git at git.haskell.org  Thu Mar 22 11:02:37 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Thu, 22 Mar 2018 11:02:37 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4394: Fixed NthCo Note (discussion in
 D4385) (28b59e4)
Message-ID: <20180322110237.9ABBD3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/tdammers/D4394
Link       : http://ghc.haskell.org/trac/ghc/changeset/28b59e41de0932958179a64985cff5557fe1fa0a/ghc

>---------------------------------------------------------------

commit 28b59e41de0932958179a64985cff5557fe1fa0a
Author: Tobias Dammers <tdammers at gmail.com>
Date:   Wed Feb 7 13:19:33 2018 +0100

    Fixed NthCo Note (discussion in D4385)
    
    https://phabricator.haskell.org/D4385#inline-34161


>---------------------------------------------------------------

28b59e41de0932958179a64985cff5557fe1fa0a
 compiler/types/TyCoRep.hs | 22 ++++++++++++++--------
 1 file changed, 14 insertions(+), 8 deletions(-)

diff --git a/compiler/types/TyCoRep.hs b/compiler/types/TyCoRep.hs
index 4614eae..b6ccc93 100644
--- a/compiler/types/TyCoRep.hs
+++ b/compiler/types/TyCoRep.hs
@@ -1181,14 +1181,20 @@ in the "Safe Coercions" paper (ICFP '14).
 
 Note [NthCo Cached Roles]
 ~~~~~~~~~~~~~~~~~~~~~~~~~
-Looking at coercionKind and coercionRole, we see that in order to find the Role
-for an NthCo, we have to know the kind; unfortunately, calculating the coercion
-kind for a nested NthCo is quadratic in the nesting depth, so we would like to
-avoid doing that as much as possible. To this end, we calculate the Role at
-construction time, and store it in the NthCo itself, thus removing the need to
-do the calculation on the fly.
-
-See Trac #11735 for the discussion that led to this.
+Why do we cache the role of NthCo in the NthCo constructor?
+Because computing role(Nth i co) involves figuring out that
+
+  co :: T tys1 ~ T tys2
+
+using coercionKind, and finding (coercionRole co), and then looking
+at the tyConRoles of T. Avoiding bad asymptotic behaviour here means
+we have to compute the kind and role of a coercion simultaneously,
+which makes the code complicated and inefficient.
+
+This only happens for NthCo. Caching the role solves the problem, and
+allows coercionKind and coercionRole to be simple.
+
+See Trac #11735
 
 Note [InstCo roles]
 ~~~~~~~~~~~~~~~~~~~


From git at git.haskell.org  Thu Mar 22 11:02:40 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Thu, 22 Mar 2018 11:02:40 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4394: Caching coercion roles in NthCo and
 coercionKindsRole refactoring (#11735) (6148776)
Message-ID: <20180322110240.635BC3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/tdammers/D4394
Link       : http://ghc.haskell.org/trac/ghc/changeset/614877624bdf59302d57a60ffd6f413a87f54997/ghc

>---------------------------------------------------------------

commit 614877624bdf59302d57a60ffd6f413a87f54997
Author: Richard Eisenberg <rae at cs.brynmawr.edu>
Date:   Fri Jan 26 22:28:42 2018 -0500

    Caching coercion roles in NthCo and coercionKindsRole refactoring (#11735)
    
    Reviewers: goldfire, bgamari
    
    Subscribers: rwbarton, thomie, carter
    
    Differential Revision: https://phabricator.haskell.org/D4394


>---------------------------------------------------------------

614877624bdf59302d57a60ffd6f413a87f54997
 docs/core-spec/CoreLint.ott  |   5 +++--
 docs/core-spec/CoreSyn.ott   |   6 ++++--
 docs/core-spec/core-spec.mng |   2 +-
 docs/core-spec/core-spec.pdf | Bin 354307 -> 355707 bytes
 4 files changed, 8 insertions(+), 5 deletions(-)

diff --git a/docs/core-spec/CoreLint.ott b/docs/core-spec/CoreLint.ott
index 3a3468d..1fb9e09 100644
--- a/docs/core-spec/CoreLint.ott
+++ b/docs/core-spec/CoreLint.ott
@@ -299,12 +299,13 @@ G |-ty ti : k2'
 not (si is_a_coercion)
 not (ti is_a_coercion)
 R' = (tyConRolesX R T)[i]
+R' <= R0
 ---------------------- :: NthCoTyCon
-G |-co nth i g : si k2~R' k2' ti
+G |-co nth R0 i g : si k2~R0 k2' ti
 
 G |-co g : (forall z1_k1.t1) k3~R k4 (forall z2_k2.t2)
 --------------------------- :: NthCoForAll
-G |-co nth 0 g : k1 *~Nom * k2
+G |-co nth R0 0 g : k1 *~R0 * k2
 
 G |-co g : (s1 s2) k~Nom k' (t1 t2)
 G |-ty s1 : k1
diff --git a/docs/core-spec/CoreSyn.ott b/docs/core-spec/CoreSyn.ott
index 78118d5..e12f68b 100644
--- a/docs/core-spec/CoreSyn.ott
+++ b/docs/core-spec/CoreSyn.ott
@@ -152,8 +152,8 @@ g {{ tex \gamma }}, h {{ tex \eta }} :: 'Coercion_' ::= {{ com Coercions, \coder
   | g1 ; g2                 ::   :: TransCo       {{ com \ctor{TransCo}: Transitivity }}
   | mu </ ti // i /> $ </ gj // j />
                             ::   :: AxiomRuleCo   {{ com \ctor{AxiomRuleCo}: Axiom-rule application (for type-nats) }}
-  | nth I g                 ::   :: NthCo         {{ com \ctor{NthCo}: Projection (0-indexed) }}
-    {{ tex \textsf{nth}^{[[I]]}\,[[g]] }}
+  | nth R I g               ::   :: NthCo         {{ com \ctor{NthCo}: Projection (0-indexed) }}
+    {{ tex \textsf{nth}^{[[I]]}_{[[R]]}\,[[g]] }}
   | LorR g                  ::   :: LRCo          {{ com \ctor{LRCo}: Left/right projection }}
   | g @ h                   ::   :: InstCo        {{ com \ctor{InstCo}: Instantiation }}
   | g |> h                  ::   :: CoherenceCo   {{ com \ctor{CoherenceCo}: Coherence }}
@@ -453,6 +453,8 @@ formula :: 'formula_' ::=
   | role_list1 = role_list2            ::   :: eq_role_list
   | R1 /= R2                           ::   :: role_neq
   | R1 = R2                            ::   :: eq_role
+  | R1 <= R2                           ::   :: lte_role
+    {{ tex [[R1]] \leq [[R2]] }}
   | </ Ki // i /> = tyConDataCons T    ::   :: tyConDataCons
   | O ( n ) = R                        ::   :: role_lookup
   | R elt role_list                    ::   :: role_elt
diff --git a/docs/core-spec/core-spec.mng b/docs/core-spec/core-spec.mng
index 5800321..64e90bb 100644
--- a/docs/core-spec/core-spec.mng
+++ b/docs/core-spec/core-spec.mng
@@ -30,7 +30,7 @@ System FC, as implemented in GHC\footnote{This
 document was originally prepared by Richard Eisenberg (\texttt{eir at cis.upenn.edu}),
 but it should be maintained by anyone who edits the functions or data structures
 mentioned in this file. Please feel free to contact Richard for more information.}\\
-\Large 23 October, 2015
+\Large 26 January, 2018
 \end{center}
 
 \section{Introduction}
diff --git a/docs/core-spec/core-spec.pdf b/docs/core-spec/core-spec.pdf
index 1e13911..3732818 100644
Binary files a/docs/core-spec/core-spec.pdf and b/docs/core-spec/core-spec.pdf differ


From git at git.haskell.org  Thu Mar 22 11:02:43 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Thu, 22 Mar 2018 11:02:43 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4394: Refactor mkCoCast (5ab47c0)
Message-ID: <20180322110243.2AF923A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/tdammers/D4394
Link       : http://ghc.haskell.org/trac/ghc/changeset/5ab47c0a152ad8aa7743403b07ad5e1962fb8f28/ghc

>---------------------------------------------------------------

commit 5ab47c0a152ad8aa7743403b07ad5e1962fb8f28
Author: Tobias Dammers <tdammers at gmail.com>
Date:   Tue Mar 6 12:09:56 2018 +0100

    Refactor mkCoCast
    
    Get rid of ugly case pattern matching in favor of simply getting the
    last two arguments unconditionally.


>---------------------------------------------------------------

5ab47c0a152ad8aa7743403b07ad5e1962fb8f28
 compiler/types/Coercion.hs | 19 +++++++------------
 1 file changed, 7 insertions(+), 12 deletions(-)

diff --git a/compiler/types/Coercion.hs b/compiler/types/Coercion.hs
index 1e529f7..33e3802 100644
--- a/compiler/types/Coercion.hs
+++ b/compiler/types/Coercion.hs
@@ -1282,22 +1282,17 @@ mkPiCo r v co | isTyVar v = mkHomoForAllCos [v] co
 -- itself always representational.
 mkCoCast :: Coercion -> CoercionR -> Coercion
 mkCoCast c g
+  | (g2:g1:_) <- reverse co_list
   = mkSymCo g1 `mkTransCo` c `mkTransCo` g2
+
+  | otherwise
+  = pprPanic "mkCoCast" (ppr g $$ ppr (coercionKind g))
   where
-       -- g  :: (s1 ~# t1) ~# (s2 ~# t2)
-       -- g1 :: s1 ~# s2
-       -- g2 :: t1 ~# t2
+    -- g  :: (s1 ~# t1) ~# (s2 ~# t2)
+    -- g1 :: s1 ~# s2
+    -- g2 :: t1 ~# t2
     (tc, _) = splitTyConApp (pFst $ coercionKind g)
-    n_args
-      | tc `hasKey` eqPrimTyConKey     = 4
-      | tc `hasKey` eqReprPrimTyConKey = 4
-      | tc `hasKey` eqTyConKey         = 3
-      | tc `hasKey` heqTyConKey        = 4
-      | tc `hasKey` coercibleTyConKey  = 3
-      | otherwise                      = pprPanic "mkCoCast" (ppr g $$ ppr (coercionKind g))
     co_list = decomposeCo (tyConArity tc) g (tyConRolesRepresentational tc)
-    g1 = co_list `getNth` (n_args - 2)
-    g2 = co_list `getNth` (n_args - 1)
 
 {-
 %************************************************************************


From git at git.haskell.org  Thu Mar 22 11:02:48 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Thu, 22 Mar 2018 11:02:48 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4394: Removed dead code (091d72d)
Message-ID: <20180322110248.B245E3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/tdammers/D4394
Link       : http://ghc.haskell.org/trac/ghc/changeset/091d72de40cbdfc9d5e9d8c118e200fa2f3afefb/ghc

>---------------------------------------------------------------

commit 091d72de40cbdfc9d5e9d8c118e200fa2f3afefb
Author: Tobias Dammers <tdammers at gmail.com>
Date:   Mon Mar 5 12:09:17 2018 +0100

    Removed dead code


>---------------------------------------------------------------

091d72de40cbdfc9d5e9d8c118e200fa2f3afefb
 compiler/types/Coercion.hs | 7 +------
 1 file changed, 1 insertion(+), 6 deletions(-)

diff --git a/compiler/types/Coercion.hs b/compiler/types/Coercion.hs
index af3cb2c..fbb8de9 100644
--- a/compiler/types/Coercion.hs
+++ b/compiler/types/Coercion.hs
@@ -13,7 +13,7 @@ module Coercion (
         Coercion, CoercionN, CoercionR, CoercionP,
         UnivCoProvenance, CoercionHole, LeftOrRight(..),
         Var, CoVar, TyCoVar,
-        Role(..), ltRole, lteRole,
+        Role(..), ltRole,
 
         -- ** Functions over coercions
         coVarTypes, coVarKind, coVarKindsTypesRole, coVarRole,
@@ -1129,11 +1129,6 @@ ltRole Representational _       = False
 ltRole Nominal          Nominal = False
 ltRole Nominal          _       = True
 
-lteRole :: Role -> Role -> Bool
--- Is one role <= the other?
--- Nominal < Representational < Phantom
-lteRole r1 r2 = r1 == r2 || r1 `ltRole` r2
-
 -------------------------------
 
 -- | like mkKindCo, but aggressively & recursively optimizes to avoid using


From git at git.haskell.org  Thu Mar 22 11:02:54 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Thu, 22 Mar 2018 11:02:54 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4394: Fix rebasing mistake (318ce2a)
Message-ID: <20180322110254.4A83F3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/tdammers/D4394
Link       : http://ghc.haskell.org/trac/ghc/changeset/318ce2a5e7398b123c21c09b53c8a51415667cdd/ghc

>---------------------------------------------------------------

commit 318ce2a5e7398b123c21c09b53c8a51415667cdd
Author: Tobias Dammers <tdammers at gmail.com>
Date:   Tue Mar 20 17:08:01 2018 +0100

    Fix rebasing mistake


>---------------------------------------------------------------

318ce2a5e7398b123c21c09b53c8a51415667cdd
 compiler/types/TyCoRep.hs | 4 ----
 libraries/array           | 2 +-
 2 files changed, 1 insertion(+), 5 deletions(-)

diff --git a/compiler/types/TyCoRep.hs b/compiler/types/TyCoRep.hs
index 6695761..3fa88a2 100644
--- a/compiler/types/TyCoRep.hs
+++ b/compiler/types/TyCoRep.hs
@@ -849,10 +849,6 @@ data Coercion
   | SymCo Coercion             -- :: e -> e
   | TransCo Coercion Coercion  -- :: e -> e -> e
 
-    -- The number coercions should match exactly the expectations
-    -- of the CoAxiomRule (i.e., the rule is fully saturated).
-  | AxiomRuleCo CoAxiomRule [Coercion]
-
   | NthCo  Role Int Coercion     -- Zero-indexed; decomposes (T t0 ... tn)
     -- :: "e" -> _ -> e0 -> e (inverse of TyConAppCo, see Note [TyConAppCo roles])
     -- Using NthCo on a ForAllCo gives an N coercion always
diff --git a/libraries/array b/libraries/array
index 1d0435f..9d63218 160000
--- a/libraries/array
+++ b/libraries/array
@@ -1 +1 @@
-Subproject commit 1d0435f4937f03901e32304e279f46ce19b0f089
+Subproject commit 9d63218fd067ff4885c0efa43b388238421a5c89


From git at git.haskell.org  Thu Mar 22 11:02:57 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Thu, 22 Mar 2018 11:02:57 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4394's head updated: Fix rebasing mistake
 (318ce2a)
Message-ID: <20180322110257.015E03A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

Branch 'wip/tdammers/D4394' now includes:

     0a778eb Revert "rts, base: Refactor stats.c to improve --machine-readable report"
     abaf43d Fix seq# case of exprOkForSpeculation
     49ac3f0 Fix #14869 by being more mindful of Type vs. Constraint
     411a97e Allow as-patterns in unidirectional patttern synonyms
     3446cee Fix two obscure bugs in rule matching
     a38a2b8 Applying patch suggested in #11735 to improve coercionKind perf
     38ee99b Added SCCs to hunt down #14683
     ecc0716 Refactored coercionKindsRole (as per #11735)
     28ff8db Simplification as per #11735
     4c94815 Caching coercion roles in NthCo (#11735)
     b2b5d3a Make mkNthCo take a Role parameter.
     6148776 Caching coercion roles in NthCo and coercionKindsRole refactoring (#11735)
     28b59e4 Fixed NthCo Note (discussion in D4385)
     766ae47 Documented invariant on cached roles
     c678314 Tighten cached role in NthCo
     8e673eb NthCo handling, assertions and documentation improvements
     4fa4034 Fixes to Coercion.hs
     091d72d Removed dead code
     0869056 Refactored setNominalRole_maybe to avoid dragging role through recursion
     c1d5e19 Another fix as per D4394
     fe5a03c Fixed unused variables
     5ab47c0 Refactor mkCoCast
     1af89d5 Fix test to reflect changed NthCo ctor
     8d7503a Increased allocation limit for T5321 on OS X
     318ce2a Fix rebasing mistake

From git at git.haskell.org  Thu Mar 22 11:02:45 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Thu, 22 Mar 2018 11:02:45 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4394: Another fix as per D4394 (c1d5e19)
Message-ID: <20180322110245.E7D333A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/tdammers/D4394
Link       : http://ghc.haskell.org/trac/ghc/changeset/c1d5e19d42817b5a0a079a32edd4311280e5e7ff/ghc

>---------------------------------------------------------------

commit c1d5e19d42817b5a0a079a32edd4311280e5e7ff
Author: Tobias Dammers <tdammers at gmail.com>
Date:   Mon Mar 5 12:50:35 2018 +0100

    Another fix as per D4394


>---------------------------------------------------------------

c1d5e19d42817b5a0a079a32edd4311280e5e7ff
 compiler/types/Coercion.hs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/compiler/types/Coercion.hs b/compiler/types/Coercion.hs
index dd4d055..8550e85 100644
--- a/compiler/types/Coercion.hs
+++ b/compiler/types/Coercion.hs
@@ -1295,7 +1295,7 @@ mkCoCast c g
       | tc `hasKey` heqTyConKey        = (4, Nominal)
       | tc `hasKey` coercibleTyConKey  = (3, Representational)
       | otherwise                      = pprPanic "mkCoCast" (ppr g $$ ppr (coercionKind g))
-    co_list = decomposeCo n_args g (replicate (n_args - 2) Nominal ++ repeat role)
+    co_list = decomposeCo (tyConArity tc) g (tyConRolesRepresentational tc)
     g1 = co_list `getNth` (n_args - 2)
     g2 = co_list `getNth` (n_args - 1)
 


From git at git.haskell.org  Thu Mar 22 11:02:51 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Thu, 22 Mar 2018 11:02:51 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4394: Increased allocation limit for
 T5321 on OS X (8d7503a)
Message-ID: <20180322110251.804CF3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/tdammers/D4394
Link       : http://ghc.haskell.org/trac/ghc/changeset/8d7503a926cb5942dfdee3357edeca3b2300cf24/ghc

>---------------------------------------------------------------

commit 8d7503a926cb5942dfdee3357edeca3b2300cf24
Author: Tobias Dammers <tdammers at gmail.com>
Date:   Sat Mar 17 17:58:52 2018 +0100

    Increased allocation limit for T5321 on OS X


>---------------------------------------------------------------

8d7503a926cb5942dfdee3357edeca3b2300cf24
 testsuite/tests/perf/compiler/all.T | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/testsuite/tests/perf/compiler/all.T b/testsuite/tests/perf/compiler/all.T
index 2afa595..f841a68 100644
--- a/testsuite/tests/perf/compiler/all.T
+++ b/testsuite/tests/perf/compiler/all.T
@@ -549,6 +549,9 @@ test('T5321Fun',
              # 2016-04-06: 279922360 x86/Linux
              # 2017-03-24: 244387620 x86/Linux (64-bit machine)
 
+            (platform('x86_64-apple-darwin'), 446893600, 5),
+             # 2018-03-17: 423774560     #  OS X-only (reason unknown, see #11753)
+
             (wordsize(64), 423774560, 5)])
              # prev:       585521080
              # 2012-08-29: 713385808     #  (increase due to new codegen)


From git at git.haskell.org  Thu Mar 22 11:27:38 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Thu, 22 Mar 2018 11:27:38 +0000 (UTC)
Subject: [commit: ghc] master: Fix over-eager constant folding in bitInteger
 (efc844f)
Message-ID: <20180322112738.3EF5C3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/efc844f5b955385d69d8e20b80d38311083a6665/ghc

>---------------------------------------------------------------

commit efc844f5b955385d69d8e20b80d38311083a6665
Author: Simon Peyton Jones <simonpj at microsoft.com>
Date:   Thu Mar 22 09:51:24 2018 +0000

    Fix over-eager constant folding in bitInteger
    
    The RULE for bitInteger was trying to constant-fold
    
        bitInteger 9223372036854775807#
    
    which meant constructing a gigantic Integer at compile
    time.  Very bad idea!  Easily fixed.
    
    Fixes Trac #14959, #14962.


>---------------------------------------------------------------

efc844f5b955385d69d8e20b80d38311083a6665
 compiler/prelude/PrelRules.hs                      | 52 +++++++++++++++-------
 testsuite/tests/simplCore/should_compile/T14959.hs |  5 +++
 testsuite/tests/simplCore/should_compile/all.T     |  1 +
 3 files changed, 42 insertions(+), 16 deletions(-)

diff --git a/compiler/prelude/PrelRules.hs b/compiler/prelude/PrelRules.hs
index 14e3f0f..9fa0db6 100644
--- a/compiler/prelude/PrelRules.hs
+++ b/compiler/prelude/PrelRules.hs
@@ -1152,7 +1152,7 @@ builtinIntegerRules =
                            ru_try = match_Integer_unop op }
           rule_bitInteger str name
            = BuiltinRule { ru_name = fsLit str, ru_fn = name, ru_nargs = 1,
-                           ru_try = match_IntToInteger_unop (bit . fromIntegral) }
+                           ru_try = match_bitInteger }
           rule_binop str name op
            = BuiltinRule { ru_name = fsLit str, ru_fn = name, ru_nargs = 2,
                            ru_try = match_Integer_binop op }
@@ -1307,22 +1307,8 @@ match_Word64ToInteger _ id_unf id [xl]
 match_Word64ToInteger _ _ _ _ = Nothing
 
 -------------------------------------------------
-match_Integer_convert :: Num a
-                      => (DynFlags -> a -> Expr CoreBndr)
-                      -> RuleFun
-match_Integer_convert convert dflags id_unf _ [xl]
-  | Just (LitInteger x _) <- exprIsLiteral_maybe id_unf xl
-  = Just (convert dflags (fromInteger x))
-match_Integer_convert _ _ _ _ _ = Nothing
-
-match_Integer_unop :: (Integer -> Integer) -> RuleFun
-match_Integer_unop unop _ id_unf _ [xl]
-  | Just (LitInteger x i) <- exprIsLiteral_maybe id_unf xl
-  = Just (Lit (LitInteger (unop x) i))
-match_Integer_unop _ _ _ _ _ = Nothing
-
 {- Note [Rewriting bitInteger]
-
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 For most types the bitInteger operation can be implemented in terms of shifts.
 The integer-gmp package, however, can do substantially better than this if
 allowed to provide its own implementation. However, in so doing it previously lost
@@ -1337,6 +1323,40 @@ should expect some funniness given that they will have at very least ignored a
 warning in this case.
 -}
 
+match_bitInteger :: RuleFun
+-- Just for GHC.Integer.Type.bitInteger :: Int# -> Integer
+match_bitInteger dflags id_unf fn [arg]
+  | Just (MachInt x) <- exprIsLiteral_maybe id_unf arg
+  , x >= 0
+  , x <= (wordSizeInBits dflags - 1)
+    -- Make sure x is small enough to yield a decently small iteger
+    -- Attempting to construct the Integer for
+    --    (bitInteger 9223372036854775807#)
+    -- would be a bad idea (Trac #14959)
+  , let x_int = fromIntegral x :: Int
+  = case splitFunTy_maybe (idType fn) of
+    Just (_, integerTy)
+      -> Just (Lit (LitInteger (bit x_int) integerTy))
+    _ -> panic "match_IntToInteger_unop: Id has the wrong type"
+
+match_bitInteger _ _ _ _ = Nothing
+
+
+-------------------------------------------------
+match_Integer_convert :: Num a
+                      => (DynFlags -> a -> Expr CoreBndr)
+                      -> RuleFun
+match_Integer_convert convert dflags id_unf _ [xl]
+  | Just (LitInteger x _) <- exprIsLiteral_maybe id_unf xl
+  = Just (convert dflags (fromInteger x))
+match_Integer_convert _ _ _ _ _ = Nothing
+
+match_Integer_unop :: (Integer -> Integer) -> RuleFun
+match_Integer_unop unop _ id_unf _ [xl]
+  | Just (LitInteger x i) <- exprIsLiteral_maybe id_unf xl
+  = Just (Lit (LitInteger (unop x) i))
+match_Integer_unop _ _ _ _ _ = Nothing
+
 match_IntToInteger_unop :: (Integer -> Integer) -> RuleFun
 match_IntToInteger_unop unop _ id_unf fn [xl]
   | Just (MachInt x) <- exprIsLiteral_maybe id_unf xl
diff --git a/testsuite/tests/simplCore/should_compile/T14959.hs b/testsuite/tests/simplCore/should_compile/T14959.hs
new file mode 100644
index 0000000..692dfdd
--- /dev/null
+++ b/testsuite/tests/simplCore/should_compile/T14959.hs
@@ -0,0 +1,5 @@
+module T14959 where
+
+import Data.Bits (setBit)
+
+f = foldl setBit 0 [x | (x,_) <- zip [0..] [1]] :: Integer
diff --git a/testsuite/tests/simplCore/should_compile/all.T b/testsuite/tests/simplCore/should_compile/all.T
index 362541e..13511ee 100644
--- a/testsuite/tests/simplCore/should_compile/all.T
+++ b/testsuite/tests/simplCore/should_compile/all.T
@@ -296,3 +296,4 @@ test('T14152a', [extra_files(['T14152.hs']), pre_cmd('cp T14152.hs T14152a.hs'),
                 compile, ['-fno-exitification -ddump-simpl'])
 test('T13990', normal, compile, ['-dcore-lint -O'])
 test('T14650', normal, compile, ['-O2'])
+test('T14959', normal, compile, ['-O'])


From git at git.haskell.org  Thu Mar 22 14:12:25 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Thu, 22 Mar 2018 14:12:25 +0000 (UTC)
Subject: [commit: ghc] branch 'wip/T14951-blunt' created
Message-ID: <20180322141225.91DC63A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

New branch : wip/T14951-blunt
Referencing: c323f19891a11d6e7a971301189e5fcd0a4f0696

From git at git.haskell.org  Thu Mar 22 14:12:28 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Thu, 22 Mar 2018 14:12:28 +0000 (UTC)
Subject: [commit: ghc] wip/T14951-blunt: Run SpecConstr twice,
 simplify in between (c323f19)
Message-ID: <20180322141228.5A03C3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/T14951-blunt
Link       : http://ghc.haskell.org/trac/ghc/changeset/c323f19891a11d6e7a971301189e5fcd0a4f0696/ghc

>---------------------------------------------------------------

commit c323f19891a11d6e7a971301189e5fcd0a4f0696
Author: Joachim Breitner <mail at joachim-breitner.de>
Date:   Mon Mar 19 15:20:57 2018 -0400

    Run SpecConstr twice, simplify in between
    
    otherwise, it does not see that certain arguments are actually useful to
    be specialized to. This gets x2n1 performance on par.


>---------------------------------------------------------------

c323f19891a11d6e7a971301189e5fcd0a4f0696
 compiler/simplCore/SimplCore.hs | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/compiler/simplCore/SimplCore.hs b/compiler/simplCore/SimplCore.hs
index 61622ae..2524f49 100644
--- a/compiler/simplCore/SimplCore.hs
+++ b/compiler/simplCore/SimplCore.hs
@@ -346,6 +346,10 @@ getCoreToDo dflags
 
         runWhen spec_constr CoreDoSpecConstr,
 
+        simpl_phase 0 ["between-core-spec"] max_iter,
+
+        runWhen spec_constr CoreDoSpecConstr,
+
         maybe_rule_check (Phase 0),
 
         runWhen late_specialise


From git at git.haskell.org  Thu Mar 22 14:18:28 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Thu, 22 Mar 2018 14:18:28 +0000 (UTC)
Subject: [commit: ghc] wip/T14951: Add testcase for #14951 (3740202)
Message-ID: <20180322141828.5015F3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/T14951
Link       : http://ghc.haskell.org/trac/ghc/changeset/37402025062fab853b58f9e8f7404d9a19105448/ghc

>---------------------------------------------------------------

commit 37402025062fab853b58f9e8f7404d9a19105448
Author: Joachim Breitner <mail at joachim-breitner.de>
Date:   Thu Mar 22 10:17:27 2018 -0400

    Add testcase for #14951


>---------------------------------------------------------------

37402025062fab853b58f9e8f7404d9a19105448
 compiler/specialise/SpecConstr.hs                  |   4 +-
 testsuite/tests/simplCore/should_compile/T14951.hs |  19 ++
 .../tests/simplCore/should_compile/T14951.stderr   | 262 +++++++++++++++++++++
 testsuite/tests/simplCore/should_compile/all.T     |   1 +
 4 files changed, 284 insertions(+), 2 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc 37402025062fab853b58f9e8f7404d9a19105448

From git at git.haskell.org  Thu Mar 22 14:34:46 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Thu, 22 Mar 2018 14:34:46 +0000 (UTC)
Subject: [commit: ghc] master: Improve shortOutIndirections slightly (034c32f)
Message-ID: <20180322143446.24F3E3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/034c32f6b8abd15eb9affca972844d3c6842af69/ghc

>---------------------------------------------------------------

commit 034c32f6b8abd15eb9affca972844d3c6842af69
Author: Simon Peyton Jones <simonpj at microsoft.com>
Date:   Thu Mar 22 14:31:45 2018 +0000

    Improve shortOutIndirections slightly
    
    I found (when investigating Trac #14955) a binding looking like
    
       Rec { exported_id = ....big...lcl_id...
           ; lcl_id = exported_id }
    
    but bizarrely 'lcl_id' was chosen as the loop breaker, and never
    inlined.  It turned out to be an unintended consequence of the
    shortOutIndirections code in SimplCore.  Easily fixed.


>---------------------------------------------------------------

034c32f6b8abd15eb9affca972844d3c6842af69
 compiler/basicTypes/BasicTypes.hs |  4 ++-
 compiler/simplCore/SimplCore.hs   | 61 +++++++++++++++++++++++----------------
 2 files changed, 39 insertions(+), 26 deletions(-)

diff --git a/compiler/basicTypes/BasicTypes.hs b/compiler/basicTypes/BasicTypes.hs
index c2f4429..9b8208e 100644
--- a/compiler/basicTypes/BasicTypes.hs
+++ b/compiler/basicTypes/BasicTypes.hs
@@ -1395,7 +1395,9 @@ pprInline = pprInline' True
 pprInlineDebug :: InlinePragma -> SDoc
 pprInlineDebug = pprInline' False
 
-pprInline' :: Bool -> InlinePragma -> SDoc
+pprInline' :: Bool           -- True <=> do not display the inl_inline field
+           -> InlinePragma
+           -> SDoc
 pprInline' emptyInline (InlinePragma { inl_inline = inline, inl_act = activation
                                     , inl_rule = info, inl_sat = mb_arity })
     = pp_inl inline <> pp_act inline activation <+> pp_sat <+> pp_info
diff --git a/compiler/simplCore/SimplCore.hs b/compiler/simplCore/SimplCore.hs
index 61622ae..a34baa8 100644
--- a/compiler/simplCore/SimplCore.hs
+++ b/compiler/simplCore/SimplCore.hs
@@ -37,7 +37,7 @@ import FloatOut         ( floatOutwards )
 import FamInstEnv
 import Id
 import ErrUtils         ( withTiming )
-import BasicTypes       ( CompilerPhase(..), isDefaultInlinePragma )
+import BasicTypes       ( CompilerPhase(..), isDefaultInlinePragma, defaultInlinePragma )
 import VarSet
 import VarEnv
 import LiberateCase     ( liberateCase )
@@ -844,16 +844,6 @@ save a gratuitous jump (from \tr{x_exported} to \tr{x_local}), and
 makes strictness information propagate better.  This used to happen in
 the final phase, but it's tidier to do it here.
 
-Note [Transferring IdInfo]
-~~~~~~~~~~~~~~~~~~~~~~~~~~
-We want to propagage any useful IdInfo on x_local to x_exported.
-
-STRICTNESS: if we have done strictness analysis, we want the strictness info on
-x_local to transfer to x_exported.  Hence the copyIdInfo call.
-
-RULES: we want to *add* any RULES for x_local to x_exported.
-
-
 Note [Messing up the exported Id's RULES]
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 We must be careful about discarding (obviously) or even merging the
@@ -947,7 +937,6 @@ unfolding for something.
 
 Note [Indirection zapping and ticks]
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
 Unfortunately this is another place where we need a special case for
 ticks. The following happens quite regularly:
 
@@ -987,12 +976,18 @@ shortOutIndirections binds
     zap (Rec pairs)       = [Rec (concatMap zapPair pairs)]
 
     zapPair (bndr, rhs)
-        | bndr `elemVarSet` exp_id_set = []
+        | bndr `elemVarSet` exp_id_set
+        = []   -- Kill the exported-id binding
+
         | Just (exp_id, ticks) <- lookupVarEnv ind_env bndr
-                                       = [(transferIdInfo exp_id bndr,
-                                           mkTicks ticks rhs),
-                                          (bndr, Var exp_id)]
-        | otherwise                    = [(bndr,rhs)]
+        , (exp_id', lcl_id') <- transferIdInfo exp_id bndr
+        =      -- Turn a local-id binding into two bindings
+               --    exp_id = rhs; lcl_id = exp_id
+          [ (exp_id', mkTicks ticks rhs),
+            (lcl_id', Var exp_id') ]
+
+        | otherwise
+        = [(bndr,rhs)]
 
 makeIndEnv :: [CoreBind] -> IndEnv
 makeIndEnv binds
@@ -1045,16 +1040,32 @@ hasShortableIdInfo id
      info = idInfo id
 
 -----------------
-transferIdInfo :: Id -> Id -> Id
+{- Note [Transferring IdInfo]
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+If we have
+     lcl_id = e; exp_id = lcl_id
+
+and lcl_id has useful IdInfo, we don't want to discard it by going
+     gbl_id = e; lcl_id = gbl_id
+
+Instead, transfer IdInfo from lcl_id to exp_id, specifically
+* (Stable) unfolding
+* Strictness
+* Rules
+* Inline pragma
+
+Overwriting, rather than merging, seems to work ok.
+
+We also zap the InlinePragma on the lcl_id. It might originally
+have had a NOINLINE, which we have now transferred; and we really
+want the lcl_id to inline now that its RHS is trivial!
+-}
+
+transferIdInfo :: Id -> Id -> (Id, Id)
 -- See Note [Transferring IdInfo]
--- If we have
---      lcl_id = e; exp_id = lcl_id
--- and lcl_id has useful IdInfo, we don't want to discard it by going
---      gbl_id = e; lcl_id = gbl_id
--- Instead, transfer IdInfo from lcl_id to exp_id
--- Overwriting, rather than merging, seems to work ok.
 transferIdInfo exported_id local_id
-  = modifyIdInfo transfer exported_id
+  = ( modifyIdInfo transfer exported_id
+    , local_id `setInlinePragma` defaultInlinePragma )
   where
     local_info = idInfo local_id
     transfer exp_info = exp_info `setStrictnessInfo`    strictnessInfo local_info


From git at git.haskell.org  Thu Mar 22 17:41:54 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Thu, 22 Mar 2018 17:41:54 +0000 (UTC)
Subject: [commit: ghc] wip/T2893: Add regression test for Trac #14961 (3c66034)
Message-ID: <20180322174154.660BF3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/T2893
Link       : http://ghc.haskell.org/trac/ghc/changeset/3c660341647cb78db461cf80a34880d84b00092f/ghc

>---------------------------------------------------------------

commit 3c660341647cb78db461cf80a34880d84b00092f
Author: Simon Peyton Jones <simonpj at microsoft.com>
Date:   Thu Mar 22 14:37:35 2018 +0000

    Add regression test for Trac #14961
    
    More precisely, for the code in comment:3


>---------------------------------------------------------------

3c660341647cb78db461cf80a34880d84b00092f
 testsuite/tests/quantified-constraints/T14961.hs | 98 ++++++++++++++++++++++++
 testsuite/tests/quantified-constraints/T9123a.hs |  2 +-
 testsuite/tests/quantified-constraints/all.T     |  1 +
 3 files changed, 100 insertions(+), 1 deletion(-)

diff --git a/testsuite/tests/quantified-constraints/T14961.hs b/testsuite/tests/quantified-constraints/T14961.hs
new file mode 100644
index 0000000..6f15ceb
--- /dev/null
+++ b/testsuite/tests/quantified-constraints/T14961.hs
@@ -0,0 +1,98 @@
+{-# LANGUAGE ConstraintKinds           #-}
+{-# LANGUAGE InstanceSigs              #-}
+{-# LANGUAGE FlexibleContexts          #-}
+{-# LANGUAGE FlexibleInstances         #-}
+{-# LANGUAGE GADTs                     #-}
+{-# LANGUAGE MultiParamTypeClasses     #-}
+{-# LANGUAGE RankNTypes                #-}
+{-# LANGUAGE TypeFamilies              #-}
+{-# LANGUAGE TypeFamilyDependencies    #-}
+{-# LANGUAGE TypeInType                #-}
+{-# LANGUAGE TypeOperators             #-}
+{-# LANGUAGE UndecidableInstances      #-}
+{-# LANGUAGE QuantifiedConstraints     #-}
+
+module T14961 where
+
+import           Data.Kind
+
+import           Control.Arrow              (left, right, (&&&), (|||))
+import           Control.Category
+import           Prelude                    hiding (id, (.))
+
+import           Data.Coerce
+
+class    (forall x. f x => g x) => f ~=> g
+instance (forall x. f x => g x) => f ~=> g
+
+type family (#) (p :: Type -> Type -> Type) (ab :: (Type, Type))
+  = (r :: Type) | r -> p ab where
+  p # '(a, b) = p a b
+
+newtype Glass
+  :: ((Type -> Type -> Type) -> Constraint)
+  -> (Type, Type) -> (Type, Type) -> Type where
+  Glass :: (forall p. z p => p # ab -> p # st) -> Glass z st ab
+
+data A_Prism
+
+type family ConstraintOf (tag :: Type)
+  = (r :: (Type -> Type -> Type) -> Constraint) where
+  ConstraintOf A_Prism = Choice
+
+_Left0
+  :: Glass Choice
+       '(Either a x, Either b x)
+       '(a, b)
+_Left0 = Glass left'
+
+_Left1
+  :: c ~=> Choice
+  => Glass c '(Either a x, Either b x) '(a, b)
+_Left1 = Glass left'
+
+-- fails with
+-- • Could not deduce (Choice p)
+-- _Left2
+--   :: (forall p. c p => ConstraintOf A_Prism p)
+--   => Glass c '(Either a x, Either b x) '(a, b)
+-- _Left2 = Glass left'
+
+_Left3
+  :: d ~ ConstraintOf A_Prism
+  => (forall p . c p => d p)
+  => Glass c
+       '(Either a x, Either b x)
+       '(a, b)
+_Left3 = Glass left'
+
+-- fails to typecheck unless at least a partial type signature is provided
+-- l :: c ~=> Choice => Glass c _ _
+-- l = _Left1 . _Left1
+
+newtype Optic o st ab where
+  Optic
+    :: (forall c d. (d ~ ConstraintOf o, c ~=> d) => Glass c st ab)
+    -> Optic o st ab
+
+_Left
+  :: Optic A_Prism
+       '(Either a x, Either b x)
+       '(a, b)
+_Left = Optic _Left1
+
+instance Category (Glass z) where
+  id :: Glass z a a
+  id = Glass id
+
+  (.) :: Glass z uv ab -> Glass z st uv -> Glass z st ab
+  Glass abuv . Glass uvst = Glass (uvst . abuv)
+
+class Profunctor (p :: Type -> Type -> Type) where
+  dimap :: (a -> b) -> (c -> d) -> p b c -> p a d
+  lmap :: (a -> b) -> p b c -> p a c
+  rmap :: (b -> c) -> p a b -> p a c
+
+class Profunctor p => Choice (p :: Type -> Type -> Type) where
+  left' :: p a b -> p (Either a c) (Either b c)
+  right' :: p a b -> p (Either c a) (Either c b)
diff --git a/testsuite/tests/quantified-constraints/T9123a.hs b/testsuite/tests/quantified-constraints/T9123a.hs
index 4e84479..53f09b9 100644
--- a/testsuite/tests/quantified-constraints/T9123a.hs
+++ b/testsuite/tests/quantified-constraints/T9123a.hs
@@ -3,7 +3,7 @@
            , UndecidableInstances
            , GeneralizedNewtypeDeriving #-}
 
-module T9123 where
+module T9123a where
 
 import Data.Coerce
 
diff --git a/testsuite/tests/quantified-constraints/all.T b/testsuite/tests/quantified-constraints/all.T
index 4f63911..fe1f091 100644
--- a/testsuite/tests/quantified-constraints/all.T
+++ b/testsuite/tests/quantified-constraints/all.T
@@ -6,6 +6,7 @@ test('T2893a', normal, compile, [''])
 test('T2893c', normal, compile, [''])
 test('T9123', normal, compile, [''])
 test('T14863', normal, compile, [''])
+test('T14961', normal, compile, [''])
 
 # Not yet
 # test('T9123a', normal, compile, [''])


From git at git.haskell.org  Thu Mar 22 20:44:18 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Thu, 22 Mar 2018 20:44:18 +0000 (UTC)
Subject: [commit: ghc] wip/T14951-blunt: Run a simplifier directly after
 SpecConstr (cbbb872)
Message-ID: <20180322204418.8FD1C3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/T14951-blunt
Link       : http://ghc.haskell.org/trac/ghc/changeset/cbbb872db8a1c265bb13503d33af3de74f9c83fe/ghc

>---------------------------------------------------------------

commit cbbb872db8a1c265bb13503d33af3de74f9c83fe
Author: Joachim Breitner <mail at joachim-breitner.de>
Date:   Thu Mar 22 16:38:10 2018 -0400

    Run a simplifier directly after SpecConstr
    
    this is to measure the effect of a second SpecConstr run on
    perf.haskell.org. The following patch on this branch will add the second
    SpecConstr run, but I want to see which of the changes are just due to
    more runs of the simplifier.


>---------------------------------------------------------------

cbbb872db8a1c265bb13503d33af3de74f9c83fe
 compiler/simplCore/SimplCore.hs | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/compiler/simplCore/SimplCore.hs b/compiler/simplCore/SimplCore.hs
index 61622ae..0905d4f 100644
--- a/compiler/simplCore/SimplCore.hs
+++ b/compiler/simplCore/SimplCore.hs
@@ -346,6 +346,8 @@ getCoreToDo dflags
 
         runWhen spec_constr CoreDoSpecConstr,
 
+        simpl_phase 0 ["between-core-spec"] max_iter,
+
         maybe_rule_check (Phase 0),
 
         runWhen late_specialise


From git at git.haskell.org  Thu Mar 22 20:44:21 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Thu, 22 Mar 2018 20:44:21 +0000 (UTC)
Subject: [commit: ghc] wip/T14951-blunt: Run SpecConstr twice,
 simplify in between (60563fd)
Message-ID: <20180322204421.5808A3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/T14951-blunt
Link       : http://ghc.haskell.org/trac/ghc/changeset/60563fdcbb40246ff3ed781cd704181b557a5400/ghc

>---------------------------------------------------------------

commit 60563fdcbb40246ff3ed781cd704181b557a5400
Author: Joachim Breitner <mail at joachim-breitner.de>
Date:   Mon Mar 19 15:20:57 2018 -0400

    Run SpecConstr twice, simplify in between
    
    otherwise, it does not see that certain arguments are actually useful to
    be specialized to. This gets x2n1 with loopification performance on par.
    But even without loopification, there is definitely stuff to be gained here:
    
    Nofib allocations
    Benchmark name		previous      change	now
    nofib/allocs/event     129683224   +   8.44%	140627312   bytes
    nofib/allocs/fulsom    243329632   -   7.83%	224287920   bytes
    nofib/allocs/mandel2	  922640   -   13.89%	   794448   bytes
    nofib/allocs/minimax	 5371584   -   8.73%	  4902576   bytes
    nofib/allocs/parstof	 3038584   -   3.63%	  2928248   bytes
    
    Nofib instruction
    Benchmark name	             previous	   change	now
    nofib/instr/compress2	    549006516	-   6.36%    514104497
    nofib/instr/fulsom	    755145483	-   3.41%    729394470
    nofib/instr/ida		    261218740	-   3.98%    250820469
    nofib/instr/k-nucleotide   2140743692	-   3.97%   2055743369
    nofib/instr/minimax	      9099200	-   4.38%      8700706


>---------------------------------------------------------------

60563fdcbb40246ff3ed781cd704181b557a5400
 compiler/simplCore/SimplCore.hs | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/compiler/simplCore/SimplCore.hs b/compiler/simplCore/SimplCore.hs
index 0905d4f..2524f49 100644
--- a/compiler/simplCore/SimplCore.hs
+++ b/compiler/simplCore/SimplCore.hs
@@ -348,6 +348,8 @@ getCoreToDo dflags
 
         simpl_phase 0 ["between-core-spec"] max_iter,
 
+        runWhen spec_constr CoreDoSpecConstr,
+
         maybe_rule_check (Phase 0),
 
         runWhen late_specialise


From git at git.haskell.org  Fri Mar 23 16:06:39 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Fri, 23 Mar 2018 16:06:39 +0000 (UTC)
Subject: [commit: ghc] master: Special-case record fields ending with hash
 when deriving Read (d5577f4)
Message-ID: <20180323160639.52ECB3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/d5577f44eaf3b9dfdfc77828038782bf818c176a/ghc

>---------------------------------------------------------------

commit d5577f44eaf3b9dfdfc77828038782bf818c176a
Author: Ryan Scott <ryan.gl.scott at gmail.com>
Date:   Fri Mar 23 11:40:02 2018 -0400

    Special-case record fields ending with hash when deriving Read
    
    Summary:
    In commit dbd81f7e86514498218572b9d978373b1699cc5b, a
    regression was inadvertently introduced which caused derived `Read`
    instances for record data types with fields ending in a `#` symbol
    (using `MagicHash`) would no longer parse on valid output. This
    is ultimately due to the same reasons as #5041, as we cannot parse
    a field name like `foo#` as a single identifier. We fix this issue
    by employing the same workaround as in #5041: first parse the
    identifier name `foo`, then then symbol `#`.
    
    This is accomplished by the new `readFieldHash` function in
    `GHC.Read`. This will likely warrant a `base-4.11.1.0` release.
    
    Test Plan: make test TEST=T14918
    
    Reviewers: tdammers, hvr, bgamari
    
    Reviewed By: bgamari
    
    Subscribers: rwbarton, thomie, carter
    
    GHC Trac Issues: #14918
    
    Differential Revision: https://phabricator.haskell.org/D4502


>---------------------------------------------------------------

d5577f44eaf3b9dfdfc77828038782bf818c176a
 compiler/prelude/PrelNames.hs                      |  3 +-
 compiler/typecheck/TcGenDeriv.hs                   | 16 ++++--
 .../{8.6.1-notes.rst => 8.4.2-notes.rst}           | 65 ++++------------------
 docs/users_guide/index.rst                         |  4 +-
 libraries/base/GHC/Read.hs                         | 17 ++++++
 libraries/base/changelog.md                        |  4 ++
 testsuite/tests/deriving/should_run/T14918.hs      | 18 ++++++
 testsuite/tests/deriving/should_run/T14918.stdout  |  2 +
 testsuite/tests/deriving/should_run/all.T          |  1 +
 9 files changed, 66 insertions(+), 64 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc d5577f44eaf3b9dfdfc77828038782bf818c176a

From git at git.haskell.org  Fri Mar 23 16:06:43 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Fri, 23 Mar 2018 16:06:43 +0000 (UTC)
Subject: [commit: ghc] master: Allow PartialTypeSignatures in standalone
 deriving contexts (affdea8)
Message-ID: <20180323160643.627413A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/affdea82bb70e5a912b679a169c6e9a230e4c93e/ghc

>---------------------------------------------------------------

commit affdea82bb70e5a912b679a169c6e9a230e4c93e
Author: Ryan Scott <ryan.gl.scott at gmail.com>
Date:   Fri Mar 23 12:06:04 2018 -0400

    Allow PartialTypeSignatures in standalone deriving contexts
    
    Summary:
    At its core, this patch is a simple tweak that allows a user
    to write:
    
    ```lang=haskell
    deriving instance _ => Eq (Foo a)
    ```
    
    Which is functionally equivalent to:
    
    ```lang=haskell
    data Foo a = ...
      deriving Eq
    ```
    
    But with the added flexibility that `StandaloneDeriving` gives you
    (namely, the ability to use it anywhere, not just in the same module
    that `Foo` was declared in). This fixes #13324, and should hopefully
    address a use case brought up in #10607.
    
    Currently, only the use of a single, extra-constraints wildcard is
    permitted in a standalone deriving declaration. Any other wildcard
    is rejected, so things like
    `deriving instance (Eq a, _) => Eq (Foo a)` are currently forbidden.
    
    There are quite a few knock-on changes brought on by this change:
    
    * The `HsSyn` type used to represent standalone-derived instances
      was previously `LHsSigType`, which isn't sufficient to hold
      wildcard types. This needed to be changed to `LHsSigWcType` as a
      result.
    
    * Previously, `DerivContext` was a simple type synonym for
      `Maybe ThetaType`, under the assumption that you'd only ever be in
      the `Nothing` case if you were in a `deriving` clause. After this
      patch, that assumption no longer holds true, as you can also be
      in this situation with standalone deriving when an
      extra-constraints wildcard is used.
    
      As a result, I changed `DerivContext` to be a proper datatype that
      reflects the new wrinkle that this patch adds, and plumbed this
      through the relevant parts of `TcDeriv` and friends.
    
    * Relatedly, the error-reporting machinery in `TcErrors` also assumed
      that if you have any unsolved constraints in a derived instance,
      then you should be able to fix it by switching over to standalone
      deriving. This was always sound advice before, but with this new
      feature, it's possible to have unsolved constraints even when
      you're standalone-deriving something!
    
      To rectify this, I tweaked some constructors of `CtOrigin` a bit
      to reflect this new subtlety.
    
    This requires updating the Haddock submodule. See my fork at
    https://github.com/RyanGlScott/haddock/commit/067d52fd4be15a1842cbb05f42d9d482de0ad3a7
    
    Test Plan: ./validate
    
    Reviewers: simonpj, goldfire, bgamari
    
    Reviewed By: simonpj
    
    Subscribers: goldfire, rwbarton, thomie, mpickering, carter
    
    GHC Trac Issues: #13324
    
    Differential Revision: https://phabricator.haskell.org/D4383


>---------------------------------------------------------------

affdea82bb70e5a912b679a169c6e9a230e4c93e
 compiler/deSugar/DsMeta.hs                         |   2 +-
 compiler/hsSyn/Convert.hs                          |   2 +-
 compiler/hsSyn/HsDecls.hs                          |  13 +-
 compiler/parser/Parser.y                           |   3 +-
 compiler/rename/RnSource.hs                        |   2 +-
 compiler/rename/RnTypes.hs                         |  34 ++++-
 compiler/typecheck/TcDeriv.hs                      | 151 ++++++++++++++++-----
 compiler/typecheck/TcDerivInfer.hs                 |  43 ++++--
 compiler/typecheck/TcDerivUtils.hs                 | 144 ++++++++++++++------
 compiler/typecheck/TcErrors.hs                     |  15 +-
 compiler/typecheck/TcRnTypes.hs                    |  27 ++--
 docs/users_guide/8.6.1-notes.rst                   |  10 ++
 docs/users_guide/glasgow_exts.rst                  |  23 +++-
 .../partial-sigs/should_compile/T13324_compile.hs  |   7 +
 testsuite/tests/partial-sigs/should_compile/all.T  |   1 +
 .../tests/partial-sigs/should_fail/T13324_fail1.hs |   8 ++
 .../partial-sigs/should_fail/T13324_fail1.stderr   |  10 ++
 .../tests/partial-sigs/should_fail/T13324_fail2.hs |  11 ++
 .../partial-sigs/should_fail/T13324_fail2.stderr   |  12 ++
 testsuite/tests/partial-sigs/should_fail/all.T     |   2 +
 utils/haddock                                      |   2 +-
 21 files changed, 401 insertions(+), 121 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc affdea82bb70e5a912b679a169c6e9a230e4c93e

From git at git.haskell.org  Sun Mar 25 19:02:18 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Sun, 25 Mar 2018 19:02:18 +0000 (UTC)
Subject: [commit: ghc] master: Support adding objects from TH (ceb9147)
Message-ID: <20180325190218.6318F3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/ceb914771aece0aa6d87339227ce406c7179d1d1/ghc

>---------------------------------------------------------------

commit ceb914771aece0aa6d87339227ce406c7179d1d1
Author: Alec Theriault <alec.theriault at gmail.com>
Date:   Sun Mar 25 13:59:27 2018 -0400

    Support adding objects from TH
    
    The user facing TH interface changes are:
    
      * 'addForeignFile' is renamed to 'addForeignSource'
      * 'qAddForeignFile'/'addForeignFile' now expect 'FilePath's
      * 'RawObject' is now a constructor for 'ForeignSrcLang'
      * 'qAddTempFile'/'addTempFile' let you request a temporary file
        from the compiler.
    
    Test Plan: unsure about this, added a TH test
    
    Reviewers: goldfire, bgamari, angerman
    
    Reviewed By: bgamari, angerman
    
    Subscribers: hsyl20, mboes, carter, simonmar, bitonic, ljli, rwbarton, thomie
    
    GHC Trac Issues: #14298
    
    Differential Revision: https://phabricator.haskell.org/D4217


>---------------------------------------------------------------

ceb914771aece0aa6d87339227ce406c7179d1d1
 compiler/main/CodeOutput.hs                        | 20 +---------
 compiler/main/DriverPipeline.hs                    |  2 +
 compiler/main/HscTypes.hs                          |  4 +-
 compiler/typecheck/TcRnTypes.hs                    |  2 +-
 compiler/typecheck/TcSplice.hs                     | 12 ++++--
 libraries/ghc-boot-th/GHC/ForeignSrcLang/Type.hs   |  2 +-
 libraries/ghci/GHCi/Message.hs                     | 39 +++++++++---------
 libraries/ghci/GHCi/TH.hs                          |  3 +-
 .../template-haskell/Language/Haskell/TH/Syntax.hs | 46 +++++++++++++++++++---
 testsuite/tests/th/T13366.hs                       |  4 +-
 testsuite/tests/th/T14298.hs                       | 24 +++++++++++
 testsuite/tests/th/T14298.stdout                   |  2 +
 testsuite/tests/th/all.T                           |  1 +
 13 files changed, 109 insertions(+), 52 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc ceb914771aece0aa6d87339227ce406c7179d1d1

From git at git.haskell.org  Sun Mar 25 19:02:33 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Sun, 25 Mar 2018 19:02:33 +0000 (UTC)
Subject: [commit: ghc] master: testsuite: Add test for #14931 (7bb1fde)
Message-ID: <20180325190233.804C33A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/7bb1fde13be3b319bb567b1faa84436600aa47ab/ghc

>---------------------------------------------------------------

commit 7bb1fde13be3b319bb567b1faa84436600aa47ab
Author: Ben Gamari <bgamari.foss at gmail.com>
Date:   Sun Mar 25 14:00:12 2018 -0400

    testsuite: Add test for #14931
    
    Reviewers: alpmestan
    
    Reviewed By: alpmestan
    
    Subscribers: rwbarton, thomie, carter
    
    GHC Trac Issues: #14931
    
    Differential Revision: https://phabricator.haskell.org/D4518


>---------------------------------------------------------------

7bb1fde13be3b319bb567b1faa84436600aa47ab
 testsuite/tests/profiling/should_compile/Makefile  |  5 +++++
 .../tests/profiling/should_compile/T14931_Bug.hs   | 24 ++++++++++++++++++++++
 .../tests/profiling/should_compile/T14931_State.hs | 15 ++++++++++++++
 testsuite/tests/profiling/should_compile/all.T     |  1 +
 4 files changed, 45 insertions(+)

diff --git a/testsuite/tests/profiling/should_compile/Makefile b/testsuite/tests/profiling/should_compile/Makefile
index 9101fbd..012890a 100644
--- a/testsuite/tests/profiling/should_compile/Makefile
+++ b/testsuite/tests/profiling/should_compile/Makefile
@@ -1,3 +1,8 @@
 TOP=../../..
 include $(TOP)/mk/boilerplate.mk
 include $(TOP)/mk/test.mk
+
+T14931:
+	"$(TEST_HC)" $(TEST_HC_OPTS) -v0 -c -O -static -dynamic-too -dynosuf dyn_o -dynhisuf dyn_hi T14931_State.hs
+	"$(TEST_HC)" $(TEST_HC_OPTS) -v0 -c -O -prof -osuf p_o -hisuf p_hi T14931_State.hs
+	"$(TEST_HC)" $(TEST_HC_OPTS) -v0 -c -O -prof -osuf p_o -hisuf p_hi T14931_Bug.hs
diff --git a/testsuite/tests/profiling/should_compile/T14931_Bug.hs b/testsuite/tests/profiling/should_compile/T14931_Bug.hs
new file mode 100644
index 0000000..4e6f213
--- /dev/null
+++ b/testsuite/tests/profiling/should_compile/T14931_Bug.hs
@@ -0,0 +1,24 @@
+{-# LANGUAGE FlexibleContexts #-}
+{-# LANGUAGE TemplateHaskell #-}
+module T14931_Bug where
+
+import Prelude (Int, IO, Bool(..), Num(..), Monad(..), not, print)
+import qualified Language.Haskell.TH.Syntax as TH
+import T14931_State
+
+wat :: IO ()
+wat = print $(let playGame []     = do
+                      (_, score) <- get
+                      return score
+                  playGame (x:xs) = do
+                      (on, score) <- get
+                      case x of
+                           'a' | on -> put (on, score + 1)
+                           'b' | on -> put (on, score - 1)
+                           'c'      -> put (not on, score)
+                           _        -> put (on, score)
+                      playGame xs
+
+                  startState :: (Bool, Int)
+                  startState = (False, 0)
+              in TH.lift (evalState (playGame "abcaaacbbcabbab") startState) )
diff --git a/testsuite/tests/profiling/should_compile/T14931_State.hs b/testsuite/tests/profiling/should_compile/T14931_State.hs
new file mode 100644
index 0000000..9008c06
--- /dev/null
+++ b/testsuite/tests/profiling/should_compile/T14931_State.hs
@@ -0,0 +1,15 @@
+{-# LANGUAGE FlexibleInstances #-}
+{-# LANGUAGE FunctionalDependencies #-}
+{-# LANGUAGE MultiParamTypeClasses #-}
+{-# LANGUAGE UndecidableInstances #-}
+module T14931_State (MonadState(..), Lazy.evalState) where
+
+import qualified Control.Monad.Trans.State.Lazy as Lazy (StateT, get, put, evalState)
+
+class Monad m => MonadState s m | m -> s where
+    get :: m s
+    put :: s -> m ()
+
+instance Monad m => MonadState s (Lazy.StateT s m) where
+    get = Lazy.get
+    put = Lazy.put
diff --git a/testsuite/tests/profiling/should_compile/all.T b/testsuite/tests/profiling/should_compile/all.T
index 1ebcb07..4664658 100644
--- a/testsuite/tests/profiling/should_compile/all.T
+++ b/testsuite/tests/profiling/should_compile/all.T
@@ -6,3 +6,4 @@ test('prof002', [only_ways(['normal']), req_profiling], compile_and_run, ['-prof
 test('T2410', [only_ways(['normal']), req_profiling], compile, ['-O2 -prof -fprof-cafs'])
 test('T5889', [only_ways(['normal']), req_profiling, extra_files(['T5889/A.hs', 'T5889/B.hs'])], multimod_compile, ['A B', '-O -prof -fno-prof-count-entries -v0'])
 test('T12790', [only_ways(['normal']), req_profiling], compile, ['-O -prof'])
+test('T14931', [only_ways(['normal']), req_profiling], run_command, ['$MAKE -s --no-print-directory T14931'])


From git at git.haskell.org  Sun Mar 25 19:02:47 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Sun, 25 Mar 2018 19:02:47 +0000 (UTC)
Subject: [commit: ghc] master: Support iOS variants elsewhere when configuring
 (10566a8)
Message-ID: <20180325190247.CA5753A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/10566a814fc07072385fc72c25158d79f25a8a36/ghc

>---------------------------------------------------------------

commit 10566a814fc07072385fc72c25158d79f25a8a36
Author: John Ericson <John.Ericson at Obsidian.Systems>
Date:   Sun Mar 25 14:00:26 2018 -0400

    Support iOS variants elsewhere when configuring
    
    Reviewers: hvr, bgamari, angerman
    
    Reviewed By: angerman
    
    Subscribers: rwbarton, thomie, erikd, carter, angerman
    
    Differential Revision: https://phabricator.haskell.org/D4513


>---------------------------------------------------------------

10566a814fc07072385fc72c25158d79f25a8a36
 aclocal.m4   | 2 +-
 configure.ac | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/aclocal.m4 b/aclocal.m4
index e19cbf2..b0a3d44 100644
--- a/aclocal.m4
+++ b/aclocal.m4
@@ -242,7 +242,7 @@ AC_DEFUN([FPTOOLS_SET_HASKELL_PLATFORM_VARS],
         linux|linux-android)
             test -z "[$]2" || eval "[$]2=OSLinux"
             ;;
-        darwin|ios)
+        darwin|ios|watchos|tvos)
             test -z "[$]2" || eval "[$]2=OSDarwin"
             ;;
         solaris2)
diff --git a/configure.ac b/configure.ac
index 1bab56d..111def2 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1190,7 +1190,7 @@ case ${TargetOS} in
     linux|linux-android|freebsd|dragonfly|netbsd|openbsd|kfreebsdgnu|gnu|solaris2)
         RtsLinkerUseMmap=1
         ;;
-    darwin|ios)
+    darwin|ios|watchos|tvos)
         # Don't use mmap on powerpc/darwin as the mmap there doesn't support
         # reallocating. Reallocating is needed to allocate jump islands just
         # after each object image. Jumps to these jump islands use relative


From git at git.haskell.org  Sun Mar 25 19:03:02 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Sun, 25 Mar 2018 19:03:02 +0000 (UTC)
Subject: [commit: ghc] master: Fix two pernicious bugs in DeriveAnyClass
 (9893042)
Message-ID: <20180325190302.F0A853A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/9893042604cda5260cb0f7b674ed5c34b419e403/ghc

>---------------------------------------------------------------

commit 9893042604cda5260cb0f7b674ed5c34b419e403
Author: Ryan Scott <ryan.gl.scott at gmail.com>
Date:   Sun Mar 25 14:00:39 2018 -0400

    Fix two pernicious bugs in DeriveAnyClass
    
    The way GHC was handling `DeriveAnyClass` was subtly wrong
    in two notable ways:
    
    * In `inferConstraintsDAC`, we were //always// bumping the `TcLevel`
      of newly created unification variables, under the assumption that
      we would always place those unification variables inside an
      implication constraint. But #14932 showed precisely the scenario
      where we had `DeriveAnyClass` //without// any of the generated
      constraints being used inside an implication, which made GHC
      incorrectly believe the unification variables were untouchable.
    * Even worse, we were using the generated unification variables from
      `inferConstraintsDAC` in every single iteration of `simplifyDeriv`.
      In #14933, however, we have a scenario where we fill in a
      unification variable with a skolem in one iteration, discard it,
      proceed on to another iteration, use the same unification variable
      (still filled in with the old skolem), and try to unify it with
      a //new// skolem! This results in an utter disaster.
    
    The root of both these problems is `inferConstraintsDAC`. This patch
    fixes the issue by no longer generating unification variables
    directly in `inferConstraintsDAC`. Instead, we store the original
    variables from a generic default type signature in `to_metas`, a new
    field of `ThetaOrigin`, and in each iteration of `simplifyDeriv`, we
    generate fresh meta tyvars (avoiding the second issue). Moreover,
    this allows us to more carefully fine-tune the `TcLevel` under which
    we create these meta tyvars, fixing the first issue.
    
    Test Plan: make test TEST="T14932 T14933"
    
    Reviewers: simonpj, bgamari
    
    Reviewed By: simonpj
    
    Subscribers: rwbarton, thomie, carter
    
    GHC Trac Issues: #14932, #14933
    
    Differential Revision: https://phabricator.haskell.org/D4507


>---------------------------------------------------------------

9893042604cda5260cb0f7b674ed5c34b419e403
 compiler/typecheck/TcDerivInfer.hs                | 106 ++++++++++++----------
 compiler/typecheck/TcDerivUtils.hs                |  97 ++++++++++++++------
 testsuite/tests/deriving/should_compile/T14932.hs |  23 +++++
 testsuite/tests/deriving/should_compile/T14933.hs |  22 +++++
 testsuite/tests/deriving/should_compile/all.T     |   2 +
 5 files changed, 171 insertions(+), 79 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc 9893042604cda5260cb0f7b674ed5c34b419e403

From git at git.haskell.org  Sun Mar 25 19:03:17 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Sun, 25 Mar 2018 19:03:17 +0000 (UTC)
Subject: [commit: ghc] master: Add Note [BLACKHOLE points to IND] (cf80995)
Message-ID: <20180325190317.6F1DE3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/cf809950efb744ca884e0e0833a80ffd50527ca1/ghc

>---------------------------------------------------------------

commit cf809950efb744ca884e0e0833a80ffd50527ca1
Author: Simon Marlow <marlowsd at gmail.com>
Date:   Sun Mar 25 14:02:16 2018 -0400

    Add Note [BLACKHOLE points to IND]
    
    Test Plan: ci
    
    Reviewers: osa1, bgamari, erikd
    
    Reviewed By: osa1
    
    Subscribers: rwbarton, thomie, carter
    
    Differential Revision: https://phabricator.haskell.org/D4517


>---------------------------------------------------------------

cf809950efb744ca884e0e0833a80ffd50527ca1
 rts/Messages.c          |  1 +
 rts/StgMiscClosures.cmm |  1 +
 rts/sm/Evac.c           | 13 +++++++++++++
 3 files changed, 15 insertions(+)

diff --git a/rts/Messages.c b/rts/Messages.c
index a9c794d..2b13b63 100644
--- a/rts/Messages.c
+++ b/rts/Messages.c
@@ -203,6 +203,7 @@ loop:
         // just been replaced with an IND by another thread in
         // updateThunk().  In which case, if we read the indirectee
         // again we should get the value.
+        // See Note [BLACKHOLE pointing to IND] in sm/Evac.c
         goto loop;
     }
 
diff --git a/rts/StgMiscClosures.cmm b/rts/StgMiscClosures.cmm
index 595d3ce..9fd5fb8 100644
--- a/rts/StgMiscClosures.cmm
+++ b/rts/StgMiscClosures.cmm
@@ -302,6 +302,7 @@ retry:
         // This could happen, if e.g. we got a BLOCKING_QUEUE that has
         // just been replaced with an IND by another thread in
         // wakeBlockingQueue().
+        // See Note [BLACKHOLE pointing to IND] in sm/Evac.c
         goto retry;
     }
 
diff --git a/rts/sm/Evac.c b/rts/sm/Evac.c
index 27f2806..06648c3 100644
--- a/rts/sm/Evac.c
+++ b/rts/sm/Evac.c
@@ -747,6 +747,19 @@ loop:
               copy(p,info,q,sizeofW(StgInd),gen_no);
               return;
           }
+          // Note [BLACKHOLE pointing to IND]
+          //
+          // BLOCKING_QUEUE can be overwritten by IND (see
+          // wakeBlockingQueue()). However, when this happens we must
+          // be updating the BLACKHOLE, so the BLACKHOLE's indirectee
+          // should now point to the value.
+          //
+          // The mutator might observe an inconsistent state, because
+          // the writes are happening in another thread, so it's
+          // possible for the mutator to follow an indirectee and find
+          // an IND. But this should never happen in the GC, because
+          // the mutators are all stopped and the writes have
+          // completed.
           ASSERT(i != &stg_IND_info);
       }
       q = r;


From git at git.haskell.org  Sun Mar 25 19:03:34 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Sun, 25 Mar 2018 19:03:34 +0000 (UTC)
Subject: [commit: ghc] master: Run C finalizers incrementally during mutation
 (f7bbc34)
Message-ID: <20180325190334.534A23A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/f7bbc343a624710ecf8f8f5eda620c4f35c90fc8/ghc

>---------------------------------------------------------------

commit f7bbc343a624710ecf8f8f5eda620c4f35c90fc8
Author: Simon Marlow <marlowsd at gmail.com>
Date:   Sun Mar 25 14:04:02 2018 -0400

    Run C finalizers incrementally during mutation
    
    With a large heap it's possible to build up a lot of finalizers
    between GCs.  We've observed GC spending up to 50% of its time running
    finalizers.  But there's no reason we have to run finalizers during
    GC, and especially no reason we have to block *all* the mutator
    threads while *one* GC thread runs finalizers one by one.
    
    I thought about a bunch of alternative ways to handle this, which are
    documented along with runSomeFinalizers() in Weak.c.  The approach I
    settled on is to have a capability run finalizers if it is idle.  So
    running finalizers is like a low-priority background thread. This
    requires some minor scheduler changes, but not much.  In the future we
    might be able to move more GC work into here (I have my eye on freeing
    large blocks, for example).
    
    Test Plan:
    * validate
    * tested on our system and saw reductions in GC pauses of 40-50%.
    
    Reviewers: bgamari, niteria, osa1, erikd
    
    Reviewed By: bgamari, osa1
    
    Subscribers: rwbarton, thomie, carter
    
    Differential Revision: https://phabricator.haskell.org/D4521


>---------------------------------------------------------------

f7bbc343a624710ecf8f8f5eda620c4f35c90fc8
 rts/Schedule.c |  14 ++++++-
 rts/Weak.c     | 119 +++++++++++++++++++++++++++++++++++++++++++++++++++------
 rts/Weak.h     |   1 +
 rts/sm/GC.c    |  25 ++++++++++++
 rts/sm/GC.h    |   2 +
 5 files changed, 149 insertions(+), 12 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc f7bbc343a624710ecf8f8f5eda620c4f35c90fc8

From git at git.haskell.org  Sun Mar 25 19:03:49 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Sun, 25 Mar 2018 19:03:49 +0000 (UTC)
Subject: [commit: ghc] master: Fix panic on module re-exports of
 DuplicateRcordFields (fb462f9)
Message-ID: <20180325190349.485953A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/fb462f948b4a10406fab84fd5878149c11aafe8a/ghc

>---------------------------------------------------------------

commit fb462f948b4a10406fab84fd5878149c11aafe8a
Author: Adam Gundry <adam at well-typed.com>
Date:   Sun Mar 25 14:05:55 2018 -0400

    Fix panic on module re-exports of DuplicateRcordFields
    
    Test Plan: new test overloadedrecflds/should_fail/T14953
    
    Reviewers: mpickering, simonpj, bgamari
    
    Reviewed By: bgamari
    
    Subscribers: rwbarton, thomie, carter
    
    GHC Trac Issues: #14953
    
    Differential Revision: https://phabricator.haskell.org/D4527


>---------------------------------------------------------------

fb462f948b4a10406fab84fd5878149c11aafe8a
 compiler/basicTypes/RdrName.hs                     |  1 +
 compiler/typecheck/TcRnExports.hs                  | 45 +++++++++++++++-------
 .../tests/overloadedrecflds/should_fail/T14953.hs  |  4 ++
 .../overloadedrecflds/should_fail/T14953.stderr    | 30 +++++++++++++++
 .../overloadedrecflds/should_fail/T14953_A.hs      |  3 ++
 .../overloadedrecflds/should_fail/T14953_B.hs      |  3 ++
 .../tests/overloadedrecflds/should_fail/all.T      |  2 +
 7 files changed, 75 insertions(+), 13 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc fb462f948b4a10406fab84fd5878149c11aafe8a

From git at git.haskell.org  Sun Mar 25 19:04:09 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Sun, 25 Mar 2018 19:04:09 +0000 (UTC)
Subject: [commit: ghc] master: document: fix trac issue #14229 (c16df60)
Message-ID: <20180325190409.7B2A03A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/c16df6061abd33c67797b1cd676a980457f52533/ghc

>---------------------------------------------------------------

commit c16df6061abd33c67797b1cd676a980457f52533
Author: Võ Anh Duy <voanhduy1512 at live.com>
Date:   Sun Mar 25 14:06:11 2018 -0400

    document: fix trac issue #14229
    
    Accroding to
    https://git.haskell.org/ghc.git/commitdiff/49672659113371c3bee691e6d913d
    f8e6f60a1d8,
    `-Wredundant-constraints` is no longer turn on by default.
    
    Reviewers: bgamari
    
    Reviewed By: bgamari
    
    Subscribers: rwbarton, thomie, carter
    
    Differential Revision: https://phabricator.haskell.org/D4528


>---------------------------------------------------------------

c16df6061abd33c67797b1cd676a980457f52533
 docs/users_guide/using-warnings.rst | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/docs/users_guide/using-warnings.rst b/docs/users_guide/using-warnings.rst
index aeb402d..b72ae42 100644
--- a/docs/users_guide/using-warnings.rst
+++ b/docs/users_guide/using-warnings.rst
@@ -685,8 +685,8 @@ of ``-W(no-)*``.
     Similar warnings are given for a redundant constraint in an instance
     declaration.
 
-    This option is on by default. As usual you can suppress it on a
-    per-module basis with :ghc-flag:`-Wno-redundant-constraints <-Wredundant-constraints>`.
+    When turning on, you can suppress it on a per-module basis with 
+    :ghc-flag:`-Wno-redundant-constraints <-Wredundant-constraints>`.
     Occasionally you may specifically want a function to have a more
     constrained signature than necessary, perhaps to leave yourself
     wiggle-room for changing the implementation without changing the


From git at git.haskell.org  Sun Mar 25 19:45:21 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Sun, 25 Mar 2018 19:45:21 +0000 (UTC)
Subject: [commit: ghc] ghc-8.4: configure: Accept version suffix in solaris
 name (06f3367)
Message-ID: <20180325194521.D82413A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : ghc-8.4
Link       : http://ghc.haskell.org/trac/ghc/changeset/06f3367c0a198c5cfc88b1b55ef59fb611631125/ghc

>---------------------------------------------------------------

commit 06f3367c0a198c5cfc88b1b55ef59fb611631125
Author: Ben Gamari <bgamari.foss at gmail.com>
Date:   Mon Mar 19 13:32:14 2018 -0400

    configure: Accept version suffix in solaris name
    
    Summary: OpenIndiana apparently reports a triple of i386-pc-solaris2.11.
    
    Reviewers: hvr
    
    Subscribers: rwbarton, thomie, erikd, carter
    
    Differential Revision: https://phabricator.haskell.org/D4487
    
    (cherry picked from commit 4fa077a2a1d6e6e7a45ef03a1075ff3c7dddb23d)


>---------------------------------------------------------------

06f3367c0a198c5cfc88b1b55ef59fb611631125
 aclocal.m4 | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/aclocal.m4 b/aclocal.m4
index 91cdd40..7c85e06 100644
--- a/aclocal.m4
+++ b/aclocal.m4
@@ -1869,6 +1869,9 @@ case "$1" in
   mips*)
     $2="mips"
     ;;
+  nios2)
+    $2="nios2"
+    ;;
   powerpc64le*)
     $2="powerpc64le"
     ;;


From git at git.haskell.org  Sun Mar 25 19:45:24 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Sun, 25 Mar 2018 19:45:24 +0000 (UTC)
Subject: [commit: ghc] ghc-8.4: configure: Accept suffix in OpenBSD triple's
 OS name (5b0eb47)
Message-ID: <20180325194524.A1B893A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : ghc-8.4
Link       : http://ghc.haskell.org/trac/ghc/changeset/5b0eb477709c013554ec62661ac2afb222317752/ghc

>---------------------------------------------------------------

commit 5b0eb477709c013554ec62661ac2afb222317752
Author: Ben Gamari <bgamari.foss at gmail.com>
Date:   Thu Mar 8 13:29:01 2018 -0500

    configure: Accept suffix in OpenBSD triple's OS name
    
    Reviewers: hvr
    
    Subscribers: rwbarton, thomie, erikd, carter
    
    Differential Revision: https://phabricator.haskell.org/D4483
    
    (cherry picked from commit a25b763fa9e09d3bf7c82fef1eaed89a7afc54f7)


>---------------------------------------------------------------

5b0eb477709c013554ec62661ac2afb222317752
 aclocal.m4 | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/aclocal.m4 b/aclocal.m4
index 7c85e06..ac20bbc 100644
--- a/aclocal.m4
+++ b/aclocal.m4
@@ -1978,8 +1978,11 @@ AC_DEFUN([GHC_CONVERT_OS],[
       linux-*|linux)
         $3="linux"
         ;;
+      openbsd*)
+        $3="openbsd"
+        ;;
       # As far as I'm aware, none of these have relevant variants
-      freebsd|netbsd|openbsd|dragonfly|hpux|linuxaout|kfreebsdgnu|freebsd2|mingw32|darwin|gnu|nextstep2|nextstep3|sunos4|ultrix|haiku)
+      freebsd|netbsd|dragonfly|hpux|linuxaout|kfreebsdgnu|freebsd2|mingw32|darwin|gnu|nextstep2|nextstep3|sunos4|ultrix|haiku)
         $3="$1"
         ;;
       aix*) # e.g. powerpc-ibm-aix7.1.3.0


From git at git.haskell.org  Sun Mar 25 19:45:28 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Sun, 25 Mar 2018 19:45:28 +0000 (UTC)
Subject: [commit: ghc] ghc-8.4: Special-case record fields ending with hash
 when deriving Read (32e1842)
Message-ID: <20180325194528.B6DCF3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : ghc-8.4
Link       : http://ghc.haskell.org/trac/ghc/changeset/32e18420b328b1f939dd92333d3b7637c26ef3a8/ghc

>---------------------------------------------------------------

commit 32e18420b328b1f939dd92333d3b7637c26ef3a8
Author: Ryan Scott <ryan.gl.scott at gmail.com>
Date:   Fri Mar 23 11:40:02 2018 -0400

    Special-case record fields ending with hash when deriving Read
    
    Summary:
    In commit dbd81f7e86514498218572b9d978373b1699cc5b, a
    regression was inadvertently introduced which caused derived `Read`
    instances for record data types with fields ending in a `#` symbol
    (using `MagicHash`) would no longer parse on valid output. This
    is ultimately due to the same reasons as #5041, as we cannot parse
    a field name like `foo#` as a single identifier. We fix this issue
    by employing the same workaround as in #5041: first parse the
    identifier name `foo`, then then symbol `#`.
    
    This is accomplished by the new `readFieldHash` function in
    `GHC.Read`. This will likely warrant a `base-4.11.1.0` release.
    
    Test Plan: make test TEST=T14918
    
    Reviewers: tdammers, hvr, bgamari
    
    Reviewed By: bgamari
    
    Subscribers: rwbarton, thomie, carter
    
    GHC Trac Issues: #14918
    
    Differential Revision: https://phabricator.haskell.org/D4502
    
    (cherry picked from commit d5577f44eaf3b9dfdfc77828038782bf818c176a)


>---------------------------------------------------------------

32e18420b328b1f939dd92333d3b7637c26ef3a8
 compiler/prelude/PrelNames.hs                     |  3 +-
 compiler/typecheck/TcGenDeriv.hs                  | 16 +++--
 docs/users_guide/8.4.2-notes.rst                  | 88 +++++++++++++++++++++++
 docs/users_guide/index.rst                        |  1 +
 libraries/base/GHC/Read.hs                        | 17 +++++
 libraries/base/changelog.md                       |  4 ++
 testsuite/tests/deriving/should_run/T14918.hs     | 18 +++++
 testsuite/tests/deriving/should_run/T14918.stdout |  2 +
 testsuite/tests/deriving/should_run/all.T         |  1 +
 9 files changed, 143 insertions(+), 7 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc 32e18420b328b1f939dd92333d3b7637c26ef3a8

From git at git.haskell.org  Sun Mar 25 19:45:31 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Sun, 25 Mar 2018 19:45:31 +0000 (UTC)
Subject: [commit: ghc] ghc-8.4: relnotes: Fix parsing of Version: field from
 Cabal file (c3a45d5)
Message-ID: <20180325194531.8427C3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : ghc-8.4
Link       : http://ghc.haskell.org/trac/ghc/changeset/c3a45d5e8272b3e9f6f0fcb2f0cf93141d06a26a/ghc

>---------------------------------------------------------------

commit c3a45d5e8272b3e9f6f0fcb2f0cf93141d06a26a
Author: Ben Gamari <bgamari.foss at gmail.com>
Date:   Mon Mar 19 13:31:46 2018 -0400

    relnotes: Fix parsing of Version: field from Cabal file
    
    Subscribers: rwbarton, thomie, carter
    
    Differential Revision: https://phabricator.haskell.org/D4491
    
    (cherry picked from commit d718023e86c8681b87f212bd64eb6ca10ac8935e)


>---------------------------------------------------------------

c3a45d5e8272b3e9f6f0fcb2f0cf93141d06a26a
 docs/users_guide/ghc_packages.py | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/docs/users_guide/ghc_packages.py b/docs/users_guide/ghc_packages.py
index d4a688b..6419834 100644
--- a/docs/users_guide/ghc_packages.py
+++ b/docs/users_guide/ghc_packages.py
@@ -8,13 +8,13 @@ from utils import build_table_from_list
 def read_cabal_file(pkg_path):
     import re
     cabal_file = open(pkg_path, 'r').read()
-    pkg_name = re.search(r'[nN]ame:\s*([-a-zA-Z0-9]+)', cabal_file)
+    pkg_name = re.search(r'^[nN]ame\s*:\s*([-a-zA-Z0-9]+)', cabal_file, re.MULTILINE)
     if pkg_name is not None:
         pkg_name = pkg_name.group(1)
     else:
         raise RuntimeError("Failed to parse `Name:` field from %s" % pkg_path)
 
-    pkg_version = re.search(r'[vV]ersion:\s*(\d+(\.\d+)*)', cabal_file)
+    pkg_version = re.search(r'^[vV]ersion\s*:\s*(\d+(\.\d+)*)', cabal_file, re.MULTILINE)
     if pkg_version is not None:
         pkg_version = pkg_version.group(1)
     else:


From git at git.haskell.org  Mon Mar 26 00:12:04 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 26 Mar 2018 00:12:04 +0000 (UTC)
Subject: [commit: ghc] master: rts/RetainerProfile: Dump closure type if
 push() fails (9a00bfb)
Message-ID: <20180326001204.B86FA3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/9a00bfba122cd7138892c934c9cc3376dc2abe98/ghc

>---------------------------------------------------------------

commit 9a00bfba122cd7138892c934c9cc3376dc2abe98
Author: Ryan Scott <ryan.gl.scott at gmail.com>
Date:   Sun Mar 25 15:33:37 2018 -0400

    rts/RetainerProfile: Dump closure type if push() fails
    
    While investigating #14947, I noticed that the `barf`ed
    error message in `push()` doesn't print out the closure type that
    causes it to crash. Let's do so.
    
    Reviewers: bgamari, erikd, simonmar
    
    Reviewed By: bgamari
    
    Subscribers: alexbiehl, rwbarton, thomie, carter
    
    Differential Revision: https://phabricator.haskell.org/D4525


>---------------------------------------------------------------

9a00bfba122cd7138892c934c9cc3376dc2abe98
 rts/RetainerProfile.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/rts/RetainerProfile.c b/rts/RetainerProfile.c
index cad3bb4..42ddae3 100644
--- a/rts/RetainerProfile.c
+++ b/rts/RetainerProfile.c
@@ -631,7 +631,7 @@ push( StgClosure *c, retainer c_child_r, StgClosure **first_child )
     case IND:
     case INVALID_OBJECT:
     default:
-        barf("Invalid object *c in push()");
+        barf("Invalid object *c in push(): %d", get_itbl(c)->type);
         return;
     }
 


From git at git.haskell.org  Mon Mar 26 00:12:18 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 26 Mar 2018 00:12:18 +0000 (UTC)
Subject: [commit: ghc] master: testsuite: Add test for #14925 (0703c00)
Message-ID: <20180326001218.BA11C3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/0703c00f7172608ee6d7ff7d422fe3755339e9bc/ghc

>---------------------------------------------------------------

commit 0703c00f7172608ee6d7ff7d422fe3755339e9bc
Author: Ben Gamari <bgamari.foss at gmail.com>
Date:   Sun Mar 25 15:33:48 2018 -0400

    testsuite: Add test for #14925
    
    Test Plan: Validate
    
    Reviewers: alpmestan
    
    Reviewed By: alpmestan
    
    Subscribers: alpmestan, leftaroundabout, rwbarton, thomie, carter
    
    GHC Trac Issues: #14925
    
    Differential Revision: https://phabricator.haskell.org/D4512


>---------------------------------------------------------------

0703c00f7172608ee6d7ff7d422fe3755339e9bc
 T14925.stdout                                  | 1 +
 testsuite/tests/typecheck/should_run/T14925.hs | 6 ++++++
 testsuite/tests/typecheck/should_run/all.T     | 1 +
 3 files changed, 8 insertions(+)

diff --git a/T14925.stdout b/T14925.stdout
new file mode 100644
index 0000000..6a44a99
--- /dev/null
+++ b/T14925.stdout
@@ -0,0 +1 @@
+Ω
diff --git a/testsuite/tests/typecheck/should_run/T14925.hs b/testsuite/tests/typecheck/should_run/T14925.hs
new file mode 100644
index 0000000..ed57a82
--- /dev/null
+++ b/testsuite/tests/typecheck/should_run/T14925.hs
@@ -0,0 +1,6 @@
+import Data.Typeable
+
+data Ω = Ω
+
+main :: IO ()
+main = print $ typeOf Ω
diff --git a/testsuite/tests/typecheck/should_run/all.T b/testsuite/tests/typecheck/should_run/all.T
index 2907612..f7643ba 100755
--- a/testsuite/tests/typecheck/should_run/all.T
+++ b/testsuite/tests/typecheck/should_run/all.T
@@ -125,3 +125,4 @@ test('T11715', exit_code(1), compile_and_run, [''])
 test('T13594a', normal, ghci_script, ['T13594a.script'])
 test('T14218', normal, compile_and_run, [''])
 test('T14236', normal, compile_and_run, [''])
+test('T14925', expect_broken(14925), compile_and_run, [''])


From git at git.haskell.org  Mon Mar 26 00:12:33 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 26 Mar 2018 00:12:33 +0000 (UTC)
Subject: [commit: ghc] master: Fix #14916 with an additional validity check in
 deriveTyData (20f14b4)
Message-ID: <20180326001233.4223F3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/20f14b4fd4eaf2c3ab375b8fc6d40ee9e6db94fd/ghc

>---------------------------------------------------------------

commit 20f14b4fd4eaf2c3ab375b8fc6d40ee9e6db94fd
Author: Ryan Scott <ryan.gl.scott at gmail.com>
Date:   Sun Mar 25 15:34:05 2018 -0400

    Fix #14916 with an additional validity check in deriveTyData
    
    Manually-written instances and standalone-derived instances
    have the benefit of having the `checkValidInstHead` function run over
    them, which catches manual instances of built-in types like `(~)` and
    `Coercible`. However, instances generated from `deriving` clauses
    weren't being passed through `checkValidInstHead`, leading to
    confusing results as in #14916.
    
    `checkValidInstHead` also has additional validity checks for language
    extensions like `FlexibleInstances` and `MultiParamTypeClasses`. Up
    until now, GHC has never required these language extensions for
    `deriving` clause, so to avoid unnecessary breakage, I opted to
    suppress these language extension checks for `deriving` clauses, just
    like we currently suppress them for `SPECIALIZE instance` pragmas.
    
    Test Plan: make test TEST=T14916
    
    Reviewers: goldfire, bgamari
    
    Reviewed By: bgamari
    
    Subscribers: rwbarton, thomie, carter
    
    GHC Trac Issues: #14916
    
    Differential Revision: https://phabricator.haskell.org/D4501


>---------------------------------------------------------------

20f14b4fd4eaf2c3ab375b8fc6d40ee9e6db94fd
 compiler/typecheck/TcDeriv.hs                      |  9 ++++++++-
 compiler/typecheck/TcType.hs                       |  2 ++
 compiler/typecheck/TcValidity.hs                   |  8 +++++---
 testsuite/tests/deriving/should_fail/T14916.hs     |  8 ++++++++
 testsuite/tests/deriving/should_fail/T14916.stderr | 10 ++++++++++
 testsuite/tests/deriving/should_fail/all.T         |  1 +
 6 files changed, 34 insertions(+), 4 deletions(-)

diff --git a/compiler/typecheck/TcDeriv.hs b/compiler/typecheck/TcDeriv.hs
index 152292d..0e7268b 100644
--- a/compiler/typecheck/TcDeriv.hs
+++ b/compiler/typecheck/TcDeriv.hs
@@ -26,6 +26,7 @@ import TcValidity( allDistinctTyVars )
 import TcClassDcl( instDeclCtxt3, tcATDefault, tcMkDeclCtxt )
 import TcEnv
 import TcGenDeriv                       -- Deriv stuff
+import TcValidity
 import InstEnv
 import Inst
 import FamInstEnv
@@ -782,8 +783,9 @@ deriveTyData tvs tc tc_args deriv_strat deriv_pred
 
         ; traceTc "derivTyData2" (vcat [ ppr tkvs ])
 
+        ; let final_tc_app = mkTyConApp tc final_tc_args
         ; checkTc (allDistinctTyVars (mkVarSet tkvs) args_to_drop)     -- (a, b, c)
-                  (derivingEtaErr cls final_cls_tys (mkTyConApp tc final_tc_args))
+                  (derivingEtaErr cls final_cls_tys final_tc_app)
                 -- Check that
                 --  (a) The args to drop are all type variables; eg reject:
                 --              data instance T a Int = .... deriving( Monad )
@@ -799,6 +801,11 @@ deriveTyData tvs tc tc_args deriv_strat deriv_pred
                 -- expand any type synonyms.
                 -- See Note [Eta-reducing type synonyms]
 
+        ; checkValidInstHead DerivClauseCtxt cls $
+                             final_cls_tys ++ [final_tc_app]
+                -- Check that we aren't deriving an instance of a magical
+                -- type like (~) or Coercible (#14916).
+
         ; spec <- mkEqnHelp Nothing tkvs
                             cls final_cls_tys tc final_tc_args
                             (InferContext Nothing) deriv_strat
diff --git a/compiler/typecheck/TcType.hs b/compiler/typecheck/TcType.hs
index de37aa8..d378fcb 100644
--- a/compiler/typecheck/TcType.hs
+++ b/compiler/typecheck/TcType.hs
@@ -617,6 +617,7 @@ data UserTypeCtxt
                         --      f :: <S> => a -> a
   | DataTyCtxt Name     -- The "stupid theta" part of a data decl
                         --      data <S> => T a = MkT a
+  | DerivClauseCtxt     -- A 'deriving' clause
 
 {-
 -- Notes re TySynCtxt
@@ -652,6 +653,7 @@ pprUserTypeCtxt (ClassSCCtxt c)   = text "the super-classes of class" <+> quotes
 pprUserTypeCtxt SigmaCtxt         = text "the context of a polymorphic type"
 pprUserTypeCtxt (DataTyCtxt tc)   = text "the context of the data type declaration for" <+> quotes (ppr tc)
 pprUserTypeCtxt (PatSynCtxt n)    = text "the signature for pattern synonym" <+> quotes (ppr n)
+pprUserTypeCtxt (DerivClauseCtxt) = text "a `deriving' clause"
 
 isSigMaybe :: UserTypeCtxt -> Maybe Name
 isSigMaybe (FunSigCtxt n _) = Just n
diff --git a/compiler/typecheck/TcValidity.hs b/compiler/typecheck/TcValidity.hs
index 3bf9f52..d2d32c6 100644
--- a/compiler/typecheck/TcValidity.hs
+++ b/compiler/typecheck/TcValidity.hs
@@ -9,7 +9,7 @@ module TcValidity (
   Rank, UserTypeCtxt(..), checkValidType, checkValidMonoType,
   ContextKind(..), expectedKindInCtxt,
   checkValidTheta, checkValidFamPats,
-  checkValidInstance, validDerivPred,
+  checkValidInstance, checkValidInstHead, validDerivPred,
   checkInstTermination, checkTySynRhs,
   ClsInstInfo, checkValidCoAxiom, checkValidCoAxBranch,
   checkValidTyFamEqn,
@@ -921,6 +921,7 @@ okIPCtxt (InstDeclCtxt {}) = False
 okIPCtxt (SpecInstCtxt {}) = False
 okIPCtxt (RuleSigCtxt {})  = False
 okIPCtxt DefaultDeclCtxt   = False
+okIPCtxt DerivClauseCtxt   = False
 
 {-
 Note [Kind polymorphic type classes]
@@ -1050,9 +1051,9 @@ checkValidInstHead ctxt clas cls_args
              checkHasFieldInst clas cls_args
 
            -- Check language restrictions;
-           -- but not for SPECIALISE instance pragmas
+           -- but not for SPECIALISE instance pragmas or deriving clauses
        ; let ty_args = filterOutInvisibleTypes (classTyCon clas) cls_args
-       ; unless spec_inst_prag $
+       ; unless (spec_inst_prag || deriv_clause) $
          do { checkTc (xopt LangExt.TypeSynonymInstances dflags ||
                        all tcInstHeadTyNotSynonym ty_args)
                  (instTypeErr clas cls_args head_type_synonym_msg)
@@ -1068,6 +1069,7 @@ checkValidInstHead ctxt clas cls_args
        ; mapM_ checkValidTypePat ty_args }
   where
     spec_inst_prag = case ctxt of { SpecInstCtxt -> True; _ -> False }
+    deriv_clause   = case ctxt of { DerivClauseCtxt -> True; _ -> False }
 
     head_type_synonym_msg = parens (
                 text "All instance types must be of the form (T t1 ... tn)" $$
diff --git a/testsuite/tests/deriving/should_fail/T14916.hs b/testsuite/tests/deriving/should_fail/T14916.hs
new file mode 100644
index 0000000..19b323f
--- /dev/null
+++ b/testsuite/tests/deriving/should_fail/T14916.hs
@@ -0,0 +1,8 @@
+{-# LANGUAGE DeriveAnyClass #-}
+module T14916 where
+
+import Data.Coerce
+import Data.Typeable
+
+data A = MkA deriving ((~) A)
+data B = MkB deriving (Coercible B)
diff --git a/testsuite/tests/deriving/should_fail/T14916.stderr b/testsuite/tests/deriving/should_fail/T14916.stderr
new file mode 100644
index 0000000..2a6cca1
--- /dev/null
+++ b/testsuite/tests/deriving/should_fail/T14916.stderr
@@ -0,0 +1,10 @@
+
+T14916.hs:7:24: error:
+    • Illegal instance declaration for ‘A ~ A’
+        Manual instances of this class are not permitted.
+    • In the data declaration for ‘A’
+
+T14916.hs:8:24: error:
+    • Illegal instance declaration for ‘Coercible B B’
+        Manual instances of this class are not permitted.
+    • In the data declaration for ‘B’
diff --git a/testsuite/tests/deriving/should_fail/all.T b/testsuite/tests/deriving/should_fail/all.T
index acd3486..8dc5b78 100644
--- a/testsuite/tests/deriving/should_fail/all.T
+++ b/testsuite/tests/deriving/should_fail/all.T
@@ -71,3 +71,4 @@ test('T14365', [extra_files(['T14365B.hs','T14365B.hs-boot'])],
                multimod_compile_fail, ['T14365A',''])
 test('T14728a', normal, compile_fail, [''])
 test('T14728b', normal, compile_fail, [''])
+test('T14916', normal, compile_fail, [''])


From git at git.haskell.org  Mon Mar 26 00:12:47 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 26 Mar 2018 00:12:47 +0000 (UTC)
Subject: [commit: ghc] master: Don't refer to blocks in debug info when -g1
 (0cbb13b)
Message-ID: <20180326001247.75C413A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/0cbb13b3dfd70b4c9665109cd6c4a150cb7b99df/ghc

>---------------------------------------------------------------

commit 0cbb13b3dfd70b4c9665109cd6c4a150cb7b99df
Author: Bartosz Nitka <niteria at gmail.com>
Date:   Sun Mar 25 15:34:27 2018 -0400

    Don't refer to blocks in debug info when -g1
    
    -g1 removes block information, but it turns out that procs can
    refer to block information through parents.
    Note [Splitting DebugBlocks] explains the parentage relationship.
    
    Test Plan:
    * ./validate
    * added a new test
    
    Reviewers: bgamari, simonmar
    
    Reviewed By: bgamari
    
    Subscribers: rwbarton, thomie, carter
    
    GHC Trac Issues: #14894
    
    Differential Revision: https://phabricator.haskell.org/D4496


>---------------------------------------------------------------

0cbb13b3dfd70b4c9665109cd6c4a150cb7b99df
 compiler/nativeGen/Dwarf.hs                                   | 11 +++++++++--
 testsuite/tests/simplCore/should_run/T14894.hs                |  9 +++++++++
 .../tests/simplCore/should_run/T14894.stdout                  |  0
 testsuite/tests/simplCore/should_run/all.T                    |  1 +
 4 files changed, 19 insertions(+), 2 deletions(-)

diff --git a/compiler/nativeGen/Dwarf.hs b/compiler/nativeGen/Dwarf.hs
index db16958..0e645a2 100644
--- a/compiler/nativeGen/Dwarf.hs
+++ b/compiler/nativeGen/Dwarf.hs
@@ -182,10 +182,17 @@ procToDwarf df prc
                          _otherwise -> showSDocDump df $ ppr $ dblLabel prc
                     , dwLabel    = dblCLabel prc
                     , dwParent   = fmap mkAsmTempDieLabel
-                                   $ mfilter (/= dblCLabel prc)
+                                   $ mfilter goodParent
                                    $ fmap dblCLabel (dblParent prc)
-                      -- Omit parent if it would be self-referential
                     }
+  where
+  goodParent a | a == dblCLabel prc = False
+               -- Omit parent if it would be self-referential
+  goodParent a | not (externallyVisibleCLabel a)
+               , debugLevel df < 2 = False
+               -- We strip block information when running -g0 or -g1, don't
+               -- refer to blocks in that case. Fixes #14894.
+  goodParent _ = True
 
 -- | Generate DWARF info for a block
 blockToDwarf :: DynFlags -> DebugBlock -> DwarfInfo
diff --git a/testsuite/tests/simplCore/should_run/T14894.hs b/testsuite/tests/simplCore/should_run/T14894.hs
new file mode 100644
index 0000000..420b85e
--- /dev/null
+++ b/testsuite/tests/simplCore/should_run/T14894.hs
@@ -0,0 +1,9 @@
+{-# OPTIONS_GHC -g1 -O #-}
+import System.Environment
+summap :: (Int -> Int) -> (Int -> Int)
+summap f n = f 10
+{-# NOINLINE summap #-}
+
+main = do
+  n <- length `fmap` getArgs
+  print $ summap (+ n) n
diff --git a/libraries/base/tests/IO/T4895.stdout b/testsuite/tests/simplCore/should_run/T14894.stdout
similarity index 100%
copy from libraries/base/tests/IO/T4895.stdout
copy to testsuite/tests/simplCore/should_run/T14894.stdout
diff --git a/testsuite/tests/simplCore/should_run/all.T b/testsuite/tests/simplCore/should_run/all.T
index d1ea496..d697605 100644
--- a/testsuite/tests/simplCore/should_run/all.T
+++ b/testsuite/tests/simplCore/should_run/all.T
@@ -82,3 +82,4 @@ test('T14768', reqlib('vector'), compile_and_run, [''])
 test('T14868',
      [when((arch('powerpc64') or arch('powerpc64le')), expect_broken(11261))],
      compile_and_run, [''])
+test('T14894', normal, compile_and_run, [''])


From git at git.haskell.org  Mon Mar 26 00:13:02 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 26 Mar 2018 00:13:02 +0000 (UTC)
Subject: [commit: ghc] master: Fix scoped type variables in TH for several
 constructs (a3986d7)
Message-ID: <20180326001302.148593A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/a3986d7fa59d96a77ac0f25bcf1dcf96b8746994/ghc

>---------------------------------------------------------------

commit a3986d7fa59d96a77ac0f25bcf1dcf96b8746994
Author: HE, Tao <sighingnow at gmail.com>
Date:   Sun Mar 25 15:34:45 2018 -0400

    Fix scoped type variables in TH for several constructs
    
    Namely class methods, default signatures and pattern synonyms.
    
    When scoped type variables occur inside class default methods,
    default signatures and pattern synonyms, avoid re-create explicit
    type variables when represent the type signatures.
    
    This patch should fix Trac#14885.
    
    Signed-off-by: HE, Tao <sighingnow at gmail.com>
    
    Test Plan: make test TEST="T14885a T14885b T14885c"
    
    Reviewers: goldfire, bgamari, simonpj, RyanGlScott
    
    Reviewed By: simonpj, RyanGlScott
    
    Subscribers: rwbarton, thomie, carter
    
    GHC Trac Issues: #14885
    
    Differential Revision: https://phabricator.haskell.org/D4469


>---------------------------------------------------------------

a3986d7fa59d96a77ac0f25bcf1dcf96b8746994
 compiler/deSugar/DsMeta.hs       | 197 ++++++++++++++++++++++++---------------
 docs/users_guide/8.6.1-notes.rst |   3 +
 testsuite/tests/th/T14885a.hs    |  18 ++++
 testsuite/tests/th/T14885b.hs    |  16 ++++
 testsuite/tests/th/T14885c.hs    |  14 +++
 testsuite/tests/th/T7064.stdout  |   4 +-
 testsuite/tests/th/all.T         |   3 +
 7 files changed, 177 insertions(+), 78 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc a3986d7fa59d96a77ac0f25bcf1dcf96b8746994

From git at git.haskell.org  Mon Mar 26 00:59:36 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 26 Mar 2018 00:59:36 +0000 (UTC)
Subject: [commit: ghc] master: llvmGen: Pass -optlo flags last to opt (41db237)
Message-ID: <20180326005936.790593A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/41db237e1290b650e52eb07323eca71de941e184/ghc

>---------------------------------------------------------------

commit 41db237e1290b650e52eb07323eca71de941e184
Author: Oleg Grenrus <oleg.grenrus at iki.fi>
Date:   Sun Mar 25 20:13:18 2018 -0400

    llvmGen: Pass -optlo flags last to opt
    
    LLVM, like GHC, processes flags in the order that they appear.
    Consequently, we need to ensure the user-provided flags appear last so
    they can override flags produced by GHC. See #14821.
    
    Test Plan: `ghc -O2 -optlo-O2 -v3 $FILE` and ensure that `opt` and `llc`
    are invoked with `-O2`.
    
    Subscribers: rwbarton, thomie, carter
    
    GHC Trac Issues: #14821
    
    Differential Revision: https://phabricator.haskell.org/D4421


>---------------------------------------------------------------

41db237e1290b650e52eb07323eca71de941e184
 compiler/main/SysTools/Tasks.hs | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/compiler/main/SysTools/Tasks.hs b/compiler/main/SysTools/Tasks.hs
index 82560af..66cc1ec 100644
--- a/compiler/main/SysTools/Tasks.hs
+++ b/compiler/main/SysTools/Tasks.hs
@@ -147,7 +147,9 @@ runLlvmOpt :: DynFlags -> [Option] -> IO ()
 runLlvmOpt dflags args = do
   let (p,args0) = pgm_lo dflags
       args1 = map Option (getOpts dflags opt_lo)
-  runSomething dflags "LLVM Optimiser" p (args0 ++ args1 ++ args)
+      -- We take care to pass -optlo flags (e.g. args0) last to ensure that the
+      -- user can override flags passed by GHC. See #14821.
+  runSomething dflags "LLVM Optimiser" p (args1 ++ args ++ args0)
 
 -- | Run the LLVM Compiler
 runLlvmLlc :: DynFlags -> [Option] -> IO ()


From git at git.haskell.org  Mon Mar 26 01:03:28 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 26 Mar 2018 01:03:28 +0000 (UTC)
Subject: [commit: ghc] ghc-8.4: Don't refer to blocks in debug info when -g1
 (59d7347)
Message-ID: <20180326010328.34A2C3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : ghc-8.4
Link       : http://ghc.haskell.org/trac/ghc/changeset/59d7347119c9f17e83b02d428f4efec823c065e1/ghc

>---------------------------------------------------------------

commit 59d7347119c9f17e83b02d428f4efec823c065e1
Author: Bartosz Nitka <niteria at gmail.com>
Date:   Sun Mar 25 15:34:27 2018 -0400

    Don't refer to blocks in debug info when -g1
    
    -g1 removes block information, but it turns out that procs can
    refer to block information through parents.
    Note [Splitting DebugBlocks] explains the parentage relationship.
    
    Test Plan:
    * ./validate
    * added a new test
    
    Reviewers: bgamari, simonmar
    
    Reviewed By: bgamari
    
    Subscribers: rwbarton, thomie, carter
    
    GHC Trac Issues: #14894
    
    Differential Revision: https://phabricator.haskell.org/D4496
    
    (cherry picked from commit 0cbb13b3dfd70b4c9665109cd6c4a150cb7b99df)


>---------------------------------------------------------------

59d7347119c9f17e83b02d428f4efec823c065e1
 compiler/nativeGen/Dwarf.hs                                   | 11 +++++++++--
 testsuite/tests/simplCore/should_run/T14894.hs                |  9 +++++++++
 .../tests/simplCore/should_run/T14894.stdout                  |  0
 testsuite/tests/simplCore/should_run/all.T                    |  1 +
 4 files changed, 19 insertions(+), 2 deletions(-)

diff --git a/compiler/nativeGen/Dwarf.hs b/compiler/nativeGen/Dwarf.hs
index b858b77..8ccf408 100644
--- a/compiler/nativeGen/Dwarf.hs
+++ b/compiler/nativeGen/Dwarf.hs
@@ -182,10 +182,17 @@ procToDwarf df prc
                          _otherwise -> showSDocDump df $ ppr $ dblLabel prc
                     , dwLabel    = dblCLabel prc
                     , dwParent   = fmap mkAsmTempDieLabel
-                                   $ mfilter (/= dblCLabel prc)
+                                   $ mfilter goodParent
                                    $ fmap dblCLabel (dblParent prc)
-                      -- Omit parent if it would be self-referential
                     }
+  where
+  goodParent a | a == dblCLabel prc = False
+               -- Omit parent if it would be self-referential
+  goodParent a | not (externallyVisibleCLabel a)
+               , debugLevel df < 2 = False
+               -- We strip block information when running -g0 or -g1, don't
+               -- refer to blocks in that case. Fixes #14894.
+  goodParent _ = True
 
 -- | Generate DWARF info for a block
 blockToDwarf :: DynFlags -> DebugBlock -> DwarfInfo
diff --git a/testsuite/tests/simplCore/should_run/T14894.hs b/testsuite/tests/simplCore/should_run/T14894.hs
new file mode 100644
index 0000000..420b85e
--- /dev/null
+++ b/testsuite/tests/simplCore/should_run/T14894.hs
@@ -0,0 +1,9 @@
+{-# OPTIONS_GHC -g1 -O #-}
+import System.Environment
+summap :: (Int -> Int) -> (Int -> Int)
+summap f n = f 10
+{-# NOINLINE summap #-}
+
+main = do
+  n <- length `fmap` getArgs
+  print $ summap (+ n) n
diff --git a/libraries/base/tests/IO/T4895.stdout b/testsuite/tests/simplCore/should_run/T14894.stdout
similarity index 100%
copy from libraries/base/tests/IO/T4895.stdout
copy to testsuite/tests/simplCore/should_run/T14894.stdout
diff --git a/testsuite/tests/simplCore/should_run/all.T b/testsuite/tests/simplCore/should_run/all.T
index d1ea496..d697605 100644
--- a/testsuite/tests/simplCore/should_run/all.T
+++ b/testsuite/tests/simplCore/should_run/all.T
@@ -82,3 +82,4 @@ test('T14768', reqlib('vector'), compile_and_run, [''])
 test('T14868',
      [when((arch('powerpc64') or arch('powerpc64le')), expect_broken(11261))],
      compile_and_run, [''])
+test('T14894', normal, compile_and_run, [''])


From git at git.haskell.org  Mon Mar 26 02:13:26 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 26 Mar 2018 02:13:26 +0000 (UTC)
Subject: [commit: ghc] master: base: Fix Unicode handling of TyCon's Show
 instance (20ae19f)
Message-ID: <20180326021326.6CD3F3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/20ae19fc7297dceaefde8d3443099bfd9cd1e905/ghc

>---------------------------------------------------------------

commit 20ae19fc7297dceaefde8d3443099bfd9cd1e905
Author: Ben Gamari <bgamari.foss at gmail.com>
Date:   Sun Mar 25 22:12:49 2018 -0400

    base: Fix Unicode handling of TyCon's Show instance
    
    Test Plan: `make test TEST=T14925`
    
    Reviewers: hvr, dfeuer
    
    Reviewed By: dfeuer
    
    Subscribers: rwbarton, thomie, carter
    
    GHC Trac Issues: #14925
    
    Differential Revision: https://phabricator.haskell.org/D4530


>---------------------------------------------------------------

20ae19fc7297dceaefde8d3443099bfd9cd1e905
 libraries/base/GHC/Show.hs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libraries/base/GHC/Show.hs b/libraries/base/GHC/Show.hs
index a7a7f89..798dff9 100644
--- a/libraries/base/GHC/Show.hs
+++ b/libraries/base/GHC/Show.hs
@@ -215,7 +215,7 @@ instance Show TyCon where
 
 -- | @since 4.9.0.0
 instance Show TrName where
-  showsPrec _ (TrNameS s) = showString (unpackCString# s)
+  showsPrec _ (TrNameS s) = showString (unpackCStringUtf8# s)
   showsPrec _ (TrNameD s) = showString s
 
 -- | @since 4.9.0.0


From git at git.haskell.org  Mon Mar 26 02:53:54 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 26 Mar 2018 02:53:54 +0000 (UTC)
Subject: [commit: ghc] master: Add new debugging flag -dinline-check (ecfb4d3)
Message-ID: <20180326025354.C20163A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/ecfb4d363daf06cda82a4b062eb4798dee99d0e3/ghc

>---------------------------------------------------------------

commit ecfb4d363daf06cda82a4b062eb4798dee99d0e3
Author: Ben Gamari <ben at smart-cactus.org>
Date:   Sun Mar 25 22:17:24 2018 -0400

    Add new debugging flag -dinline-check
    
    This flag reports a summary of the inlining decision for identifiers
    prefixed by the flag's argument.
    
    For example, `-dinline-check foo` will report why definitions whose
    prefix is `foo` are inlined or not.
    
    Previously the only way to get this information was to pass a
    combination of `-dverbose-core2core` and `-ddump-inlinings`.
    
    This combination led to a log of 12 million lines in a module of about
    200 lines I recently had to apply it to. This flag provides a much more
    direct way to find the occurence you care about.
    
    Reviewers: osa1, dfeuer, bgamari
    
    Reviewed By: bgamari
    
    Subscribers: rwbarton, thomie, carter
    
    Differential Revision: https://phabricator.haskell.org/D4458


>---------------------------------------------------------------

ecfb4d363daf06cda82a4b062eb4798dee99d0e3
 compiler/coreSyn/CoreUnfold.hs             | 24 +++++++++++++++---------
 compiler/main/DynFlags.hs                  |  4 ++++
 docs/users_guide/debugging.rst             | 14 ++++++++++++++
 testsuite/tests/driver/all.T               |  1 +
 testsuite/tests/driver/inline-check.hs     | 12 ++++++++++++
 testsuite/tests/driver/inline-check.stderr | 26 ++++++++++++++++++++++++++
 6 files changed, 72 insertions(+), 9 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc ecfb4d363daf06cda82a4b062eb4798dee99d0e3

From git at git.haskell.org  Mon Mar 26 03:17:36 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 26 Mar 2018 03:17:36 +0000 (UTC)
Subject: [commit: ghc] master: Add unaligned bytearray access primops. Fixes
 #4442. (efd70cf)
Message-ID: <20180326031736.928FF3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/efd70cfb4b0b9932a880ab417d75eaf95da3d5e6/ghc

>---------------------------------------------------------------

commit efd70cfb4b0b9932a880ab417d75eaf95da3d5e6
Author: Reiner Pope <reinerp at google.com>
Date:   Sun Mar 25 23:16:03 2018 -0400

    Add unaligned bytearray access primops. Fixes #4442.
    
    Reviewers: bgamari, simonmar
    
    Reviewed By: bgamari
    
    Subscribers: dfeuer, rwbarton, thomie, carter
    
    GHC Trac Issues: #4442
    
    Differential Revision: https://phabricator.haskell.org/D4488


>---------------------------------------------------------------

efd70cfb4b0b9932a880ab417d75eaf95da3d5e6
 compiler/codeGen/StgCmmPrim.hs                  |  53 +++++
 compiler/prelude/primops.txt.pp                 | 210 +++++++++++++++++++
 testsuite/tests/primops/should_run/T4442.hs     | 257 ++++++++++++++++++++++++
 testsuite/tests/primops/should_run/T4442.stdout |  21 ++
 testsuite/tests/primops/should_run/all.T        |   3 +-
 5 files changed, 543 insertions(+), 1 deletion(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc efd70cfb4b0b9932a880ab417d75eaf95da3d5e6

From git at git.haskell.org  Mon Mar 26 03:50:23 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 26 Mar 2018 03:50:23 +0000 (UTC)
Subject: [commit: ghc] ghc-8.4: Fix #14916 with an additional validity check
 in deriveTyData (1887441)
Message-ID: <20180326035023.19A213A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : ghc-8.4
Link       : http://ghc.haskell.org/trac/ghc/changeset/1887441a84e3adde7db48d6459db9a47fc6cc8e2/ghc

>---------------------------------------------------------------

commit 1887441a84e3adde7db48d6459db9a47fc6cc8e2
Author: Ryan Scott <ryan.gl.scott at gmail.com>
Date:   Sun Mar 25 15:34:05 2018 -0400

    Fix #14916 with an additional validity check in deriveTyData
    
    Manually-written instances and standalone-derived instances
    have the benefit of having the `checkValidInstHead` function run over
    them, which catches manual instances of built-in types like `(~)` and
    `Coercible`. However, instances generated from `deriving` clauses
    weren't being passed through `checkValidInstHead`, leading to
    confusing results as in #14916.
    
    `checkValidInstHead` also has additional validity checks for language
    extensions like `FlexibleInstances` and `MultiParamTypeClasses`. Up
    until now, GHC has never required these language extensions for
    `deriving` clause, so to avoid unnecessary breakage, I opted to
    suppress these language extension checks for `deriving` clauses, just
    like we currently suppress them for `SPECIALIZE instance` pragmas.
    
    Test Plan: make test TEST=T14916
    
    Reviewers: goldfire, bgamari
    
    Reviewed By: bgamari
    
    Subscribers: rwbarton, thomie, carter
    
    GHC Trac Issues: #14916
    
    Differential Revision: https://phabricator.haskell.org/D4501
    
    (cherry picked from commit 20f14b4fd4eaf2c3ab375b8fc6d40ee9e6db94fd)


>---------------------------------------------------------------

1887441a84e3adde7db48d6459db9a47fc6cc8e2
 compiler/typecheck/TcDeriv.hs                      |  9 ++++++++-
 compiler/typecheck/TcType.hs                       |  2 ++
 compiler/typecheck/TcValidity.hs                   |  8 +++++---
 testsuite/tests/deriving/should_fail/T14916.hs     |  8 ++++++++
 testsuite/tests/deriving/should_fail/T14916.stderr | 10 ++++++++++
 testsuite/tests/deriving/should_fail/all.T         |  1 +
 6 files changed, 34 insertions(+), 4 deletions(-)

diff --git a/compiler/typecheck/TcDeriv.hs b/compiler/typecheck/TcDeriv.hs
index a93712c..f15c003 100644
--- a/compiler/typecheck/TcDeriv.hs
+++ b/compiler/typecheck/TcDeriv.hs
@@ -26,6 +26,7 @@ import TcValidity( allDistinctTyVars )
 import TcClassDcl( instDeclCtxt3, tcATDefault, tcMkDeclCtxt )
 import TcEnv
 import TcGenDeriv                       -- Deriv stuff
+import TcValidity
 import InstEnv
 import Inst
 import FamInstEnv
@@ -742,8 +743,9 @@ deriveTyData tvs tc tc_args deriv_strat deriv_pred
 
         ; traceTc "derivTyData2" (vcat [ ppr tkvs ])
 
+        ; let final_tc_app = mkTyConApp tc final_tc_args
         ; checkTc (allDistinctTyVars (mkVarSet tkvs) args_to_drop)     -- (a, b, c)
-                  (derivingEtaErr cls final_cls_tys (mkTyConApp tc final_tc_args))
+                  (derivingEtaErr cls final_cls_tys final_tc_app)
                 -- Check that
                 --  (a) The args to drop are all type variables; eg reject:
                 --              data instance T a Int = .... deriving( Monad )
@@ -759,6 +761,11 @@ deriveTyData tvs tc tc_args deriv_strat deriv_pred
                 -- expand any type synonyms.
                 -- See Note [Eta-reducing type synonyms]
 
+        ; checkValidInstHead DerivClauseCtxt cls $
+                             final_cls_tys ++ [final_tc_app]
+                -- Check that we aren't deriving an instance of a magical
+                -- type like (~) or Coercible (#14916).
+
         ; spec <- mkEqnHelp Nothing tkvs
                             cls final_cls_tys tc final_tc_args
                             Nothing deriv_strat
diff --git a/compiler/typecheck/TcType.hs b/compiler/typecheck/TcType.hs
index ba3cd6f..f6343da 100644
--- a/compiler/typecheck/TcType.hs
+++ b/compiler/typecheck/TcType.hs
@@ -617,6 +617,7 @@ data UserTypeCtxt
                         --      f :: <S> => a -> a
   | DataTyCtxt Name     -- The "stupid theta" part of a data decl
                         --      data <S> => T a = MkT a
+  | DerivClauseCtxt     -- A 'deriving' clause
 
 {-
 -- Notes re TySynCtxt
@@ -652,6 +653,7 @@ pprUserTypeCtxt (ClassSCCtxt c)   = text "the super-classes of class" <+> quotes
 pprUserTypeCtxt SigmaCtxt         = text "the context of a polymorphic type"
 pprUserTypeCtxt (DataTyCtxt tc)   = text "the context of the data type declaration for" <+> quotes (ppr tc)
 pprUserTypeCtxt (PatSynCtxt n)    = text "the signature for pattern synonym" <+> quotes (ppr n)
+pprUserTypeCtxt (DerivClauseCtxt) = text "a `deriving' clause"
 
 isSigMaybe :: UserTypeCtxt -> Maybe Name
 isSigMaybe (FunSigCtxt n _) = Just n
diff --git a/compiler/typecheck/TcValidity.hs b/compiler/typecheck/TcValidity.hs
index 8c01460..6b3b24d 100644
--- a/compiler/typecheck/TcValidity.hs
+++ b/compiler/typecheck/TcValidity.hs
@@ -9,7 +9,7 @@ module TcValidity (
   Rank, UserTypeCtxt(..), checkValidType, checkValidMonoType,
   ContextKind(..), expectedKindInCtxt,
   checkValidTheta, checkValidFamPats,
-  checkValidInstance, validDerivPred,
+  checkValidInstance, checkValidInstHead, validDerivPred,
   checkInstTermination, checkTySynRhs,
   ClsInstInfo, checkValidCoAxiom, checkValidCoAxBranch,
   checkValidTyFamEqn,
@@ -915,6 +915,7 @@ okIPCtxt (InstDeclCtxt {}) = False
 okIPCtxt (SpecInstCtxt {}) = False
 okIPCtxt (RuleSigCtxt {})  = False
 okIPCtxt DefaultDeclCtxt   = False
+okIPCtxt DerivClauseCtxt   = False
 
 {-
 Note [Kind polymorphic type classes]
@@ -1044,9 +1045,9 @@ checkValidInstHead ctxt clas cls_args
              checkHasFieldInst clas cls_args
 
            -- Check language restrictions;
-           -- but not for SPECIALISE instance pragmas
+           -- but not for SPECIALISE instance pragmas or deriving clauses
        ; let ty_args = filterOutInvisibleTypes (classTyCon clas) cls_args
-       ; unless spec_inst_prag $
+       ; unless (spec_inst_prag || deriv_clause) $
          do { checkTc (xopt LangExt.TypeSynonymInstances dflags ||
                        all tcInstHeadTyNotSynonym ty_args)
                  (instTypeErr clas cls_args head_type_synonym_msg)
@@ -1062,6 +1063,7 @@ checkValidInstHead ctxt clas cls_args
        ; mapM_ checkValidTypePat ty_args }
   where
     spec_inst_prag = case ctxt of { SpecInstCtxt -> True; _ -> False }
+    deriv_clause   = case ctxt of { DerivClauseCtxt -> True; _ -> False }
 
     head_type_synonym_msg = parens (
                 text "All instance types must be of the form (T t1 ... tn)" $$
diff --git a/testsuite/tests/deriving/should_fail/T14916.hs b/testsuite/tests/deriving/should_fail/T14916.hs
new file mode 100644
index 0000000..19b323f
--- /dev/null
+++ b/testsuite/tests/deriving/should_fail/T14916.hs
@@ -0,0 +1,8 @@
+{-# LANGUAGE DeriveAnyClass #-}
+module T14916 where
+
+import Data.Coerce
+import Data.Typeable
+
+data A = MkA deriving ((~) A)
+data B = MkB deriving (Coercible B)
diff --git a/testsuite/tests/deriving/should_fail/T14916.stderr b/testsuite/tests/deriving/should_fail/T14916.stderr
new file mode 100644
index 0000000..2a6cca1
--- /dev/null
+++ b/testsuite/tests/deriving/should_fail/T14916.stderr
@@ -0,0 +1,10 @@
+
+T14916.hs:7:24: error:
+    • Illegal instance declaration for ‘A ~ A’
+        Manual instances of this class are not permitted.
+    • In the data declaration for ‘A’
+
+T14916.hs:8:24: error:
+    • Illegal instance declaration for ‘Coercible B B’
+        Manual instances of this class are not permitted.
+    • In the data declaration for ‘B’
diff --git a/testsuite/tests/deriving/should_fail/all.T b/testsuite/tests/deriving/should_fail/all.T
index acd3486..8dc5b78 100644
--- a/testsuite/tests/deriving/should_fail/all.T
+++ b/testsuite/tests/deriving/should_fail/all.T
@@ -71,3 +71,4 @@ test('T14365', [extra_files(['T14365B.hs','T14365B.hs-boot'])],
                multimod_compile_fail, ['T14365A',''])
 test('T14728a', normal, compile_fail, [''])
 test('T14728b', normal, compile_fail, [''])
+test('T14916', normal, compile_fail, [''])


From git at git.haskell.org  Mon Mar 26 03:50:32 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 26 Mar 2018 03:50:32 +0000 (UTC)
Subject: [commit: ghc] ghc-8.4: base: Fix Unicode handling of TyCon's Show
 instance (b88228d)
Message-ID: <20180326035032.B3C4A3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : ghc-8.4
Link       : http://ghc.haskell.org/trac/ghc/changeset/b88228d5af6a795fc6bf7582160f271b23608fbe/ghc

>---------------------------------------------------------------

commit b88228d5af6a795fc6bf7582160f271b23608fbe
Author: Ben Gamari <bgamari.foss at gmail.com>
Date:   Sun Mar 25 22:12:49 2018 -0400

    base: Fix Unicode handling of TyCon's Show instance
    
    Test Plan: `make test TEST=T14925`
    
    Reviewers: hvr, dfeuer
    
    Reviewed By: dfeuer
    
    Subscribers: rwbarton, thomie, carter
    
    GHC Trac Issues: #14925
    
    Differential Revision: https://phabricator.haskell.org/D4530
    
    (cherry picked from commit 20ae19fc7297dceaefde8d3443099bfd9cd1e905)


>---------------------------------------------------------------

b88228d5af6a795fc6bf7582160f271b23608fbe
 libraries/base/GHC/Show.hs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libraries/base/GHC/Show.hs b/libraries/base/GHC/Show.hs
index d1c6075..b639681 100644
--- a/libraries/base/GHC/Show.hs
+++ b/libraries/base/GHC/Show.hs
@@ -208,7 +208,7 @@ instance Show TyCon where
 
 -- | @since 4.9.0.0
 instance Show TrName where
-  showsPrec _ (TrNameS s) = showString (unpackCString# s)
+  showsPrec _ (TrNameS s) = showString (unpackCStringUtf8# s)
   showsPrec _ (TrNameD s) = showString s
 
 -- | @since 4.9.0.0


From git at git.haskell.org  Mon Mar 26 05:29:58 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 26 Mar 2018 05:29:58 +0000 (UTC)
Subject: [commit: ghc] ghc-8.4: Slighly improve infix con app pattern errors
 (161467c)
Message-ID: <20180326052958.74CBA3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : ghc-8.4
Link       : http://ghc.haskell.org/trac/ghc/changeset/161467c13eee5e5aadd6595be232587f8d52293a/ghc

>---------------------------------------------------------------

commit 161467c13eee5e5aadd6595be232587f8d52293a
Author: Ömer Sinan Ağacan <omeragacan at gmail.com>
Date:   Wed Mar 14 09:16:51 2018 +0300

    Slighly improve infix con app pattern errors
    
    Given this program:
    
        main = do
          f $ do
            a <- return 3
              c <- do
              return 5
    
    GHC previously gave this error message:
    
        Main.hs:2:7: error:
            Parse error in pattern: do a <- return 3 c
            Possibly caused by a missing 'do'?
          |
        2 |   f $ do
          |       ^^...
    
    What happened is GHC considered the whole `f $ do a <- return 3 c` as a
    pattern. When parsed as an expression it becomes an infix application of
    `($)`, and GHC checks left and right hand sides before checking if `($)`
    is a valid infix constructor name, and shows the first error it got.
    
    If instead we first check if the infix op is valid in pattern context,
    the error message becomes much clearer:
    
        Main.hs:2:3: error:
            Parse error in pattern: f $ do a <- return 3 c
            Possibly caused by a missing 'do'?
          |
        2 |   f $ do
          |   ^^^^^^...
    
    This may not entirely fix #11188 but I think it's an improvement.
    
    Reviewers: bgamari
    
    Reviewed By: bgamari
    
    Subscribers: rwbarton, thomie, carter
    
    GHC Trac Issues: #11188
    
    Differential Revision: https://phabricator.haskell.org/D4497
    
    (cherry picked from commit cb6d8589c83247ec96d5faa82df3e93f419bbfe0)


>---------------------------------------------------------------

161467c13eee5e5aadd6595be232587f8d52293a
 compiler/parser/RdrHsSyn.hs                              | 13 +++++++------
 testsuite/tests/parser/should_fail/InfixAppPatErr.hs     |  5 +++++
 testsuite/tests/parser/should_fail/InfixAppPatErr.stderr |  4 ++++
 testsuite/tests/parser/should_fail/all.T                 |  1 +
 4 files changed, 17 insertions(+), 6 deletions(-)

diff --git a/compiler/parser/RdrHsSyn.hs b/compiler/parser/RdrHsSyn.hs
index 126e92e..119c5c6 100644
--- a/compiler/parser/RdrHsSyn.hs
+++ b/compiler/parser/RdrHsSyn.hs
@@ -875,12 +875,13 @@ checkAPat msg loc e0 = do
                       | extopt LangExt.NPlusKPatterns opts && (plus == plus_RDR)
                       -> return (mkNPlusKPat (L nloc n) (L lloc lit))
 
-   OpApp l op _fix r  -> do l <- checkLPat msg l
-                            r <- checkLPat msg r
-                            case op of
-                               L cl (HsVar (L _ c)) | isDataOcc (rdrNameOcc c)
-                                      -> return (ConPatIn (L cl c) (InfixCon l r))
-                               _ -> patFail msg loc e0
+   OpApp l (L cl (HsVar (L _ c))) _fix r
+     | isDataOcc (rdrNameOcc c) -> do
+         l <- checkLPat msg l
+         r <- checkLPat msg r
+         return (ConPatIn (L cl c) (InfixCon l r))
+
+   OpApp _l _op _fix _r -> patFail msg loc e0
 
    HsPar e            -> checkLPat msg e >>= (return . ParPat)
    ExplicitList _ _ es  -> do ps <- mapM (checkLPat msg) es
diff --git a/testsuite/tests/parser/should_fail/InfixAppPatErr.hs b/testsuite/tests/parser/should_fail/InfixAppPatErr.hs
new file mode 100644
index 0000000..5a56f71
--- /dev/null
+++ b/testsuite/tests/parser/should_fail/InfixAppPatErr.hs
@@ -0,0 +1,5 @@
+main = do
+  f $ do
+    a <- return 3
+      c <- do
+      return 5
diff --git a/testsuite/tests/parser/should_fail/InfixAppPatErr.stderr b/testsuite/tests/parser/should_fail/InfixAppPatErr.stderr
new file mode 100644
index 0000000..69839e3
--- /dev/null
+++ b/testsuite/tests/parser/should_fail/InfixAppPatErr.stderr
@@ -0,0 +1,4 @@
+
+InfixAppPatErr.hs:2:3: error:
+    Parse error in pattern: f $ do a <- return 3 c
+    Possibly caused by a missing 'do'?
diff --git a/testsuite/tests/parser/should_fail/all.T b/testsuite/tests/parser/should_fail/all.T
index abe3da9..503cab3 100644
--- a/testsuite/tests/parser/should_fail/all.T
+++ b/testsuite/tests/parser/should_fail/all.T
@@ -102,3 +102,4 @@ test('T8501a', normal, compile_fail, [''])
 test('T8501b', normal, compile_fail, [''])
 test('T8501c', normal, compile_fail, [''])
 test('T12610', normal, compile_fail, [''])
+test('InfixAppPatErr', normal, compile_fail, [''])


From git at git.haskell.org  Mon Mar 26 05:30:13 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 26 Mar 2018 05:30:13 +0000 (UTC)
Subject: [commit: ghc] ghc-8.4: Fix a debug print in disassembler (#14905)
 (bd85d96)
Message-ID: <20180326053013.701633A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : ghc-8.4
Link       : http://ghc.haskell.org/trac/ghc/changeset/bd85d96305bf7e70d0dda957fcc3124f2b04e410/ghc

>---------------------------------------------------------------

commit bd85d96305bf7e70d0dda957fcc3124f2b04e410
Author: Ömer Sinan Ağacan <omeragacan at gmail.com>
Date:   Fri Mar 9 15:38:58 2018 +0300

    Fix a debug print in disassembler (#14905)
    
    When interpreter is not profiled (see `interpreterProfiled` in
    `DynFlags`) bytecode generator generates a NULL pointer as the cost
    centre of a `BRK_FUN` instruction:
    
        let cc | interpreterProfiled dflags = cc_arr ! tick_no
               | otherwise = toRemotePtr nullPtr
        let breakInstr = BRK_FUN (fromIntegral tick_no) (getUnique this_mod) cc
        return $ breakInstr `consOL` code
    
    We now take this into account when disassembling `BRK_FUN`.
    
    Reviewers: bgamari, simonmar, erikd
    
    Subscribers: rwbarton, thomie, carter
    
    Differential Revision: https://phabricator.haskell.org/D4490
    
    (cherry picked from commit 8e3410134bd7419db638988d74fcc600b03e2a1a)


>---------------------------------------------------------------

bd85d96305bf7e70d0dda957fcc3124f2b04e410
 rts/Disassembler.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/rts/Disassembler.c b/rts/Disassembler.c
index 8c84e13..01d6c3b 100644
--- a/rts/Disassembler.c
+++ b/rts/Disassembler.c
@@ -68,7 +68,11 @@ disInstr ( StgBCO *bco, int pc )
       case bci_BRK_FUN:
          debugBelch ("BRK_FUN  " );  printPtr( ptrs[instrs[pc]] );
          debugBelch (" %d ", instrs[pc+1]); printPtr( ptrs[instrs[pc+2]] );
-         debugBelch(" %s\n", ((CostCentre*)(literals[instrs[pc+3]]))->label);
+         CostCentre* cc = (CostCentre*)literals[instrs[pc+3]];
+         if (cc) {
+           debugBelch(" %s", cc->label);
+         }
+         debugBelch("\n");
          pc += 4;
          break;
       case bci_SWIZZLE:


From git at git.haskell.org  Mon Mar 26 05:30:23 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 26 Mar 2018 05:30:23 +0000 (UTC)
Subject: [commit: ghc] ghc-8.4: Fix over-eager constant folding in bitInteger
 (3c6a057)
Message-ID: <20180326053023.7F62A3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : ghc-8.4
Link       : http://ghc.haskell.org/trac/ghc/changeset/3c6a0578b5a05ce1e8c0089975fdff55aa8747fd/ghc

>---------------------------------------------------------------

commit 3c6a0578b5a05ce1e8c0089975fdff55aa8747fd
Author: Simon Peyton Jones <simonpj at microsoft.com>
Date:   Thu Mar 22 09:51:24 2018 +0000

    Fix over-eager constant folding in bitInteger
    
    The RULE for bitInteger was trying to constant-fold
    
        bitInteger 9223372036854775807#
    
    which meant constructing a gigantic Integer at compile
    time.  Very bad idea!  Easily fixed.
    
    Fixes Trac #14959, #14962.
    
    (cherry picked from commit efc844f5b955385d69d8e20b80d38311083a6665)


>---------------------------------------------------------------

3c6a0578b5a05ce1e8c0089975fdff55aa8747fd
 compiler/prelude/PrelRules.hs                      | 52 +++++++++++++++-------
 testsuite/tests/simplCore/should_compile/T14959.hs |  5 +++
 testsuite/tests/simplCore/should_compile/all.T     |  1 +
 3 files changed, 42 insertions(+), 16 deletions(-)

diff --git a/compiler/prelude/PrelRules.hs b/compiler/prelude/PrelRules.hs
index b475637..867c12f 100644
--- a/compiler/prelude/PrelRules.hs
+++ b/compiler/prelude/PrelRules.hs
@@ -1090,7 +1090,7 @@ builtinIntegerRules =
                            ru_try = match_Integer_unop op }
           rule_bitInteger str name
            = BuiltinRule { ru_name = fsLit str, ru_fn = name, ru_nargs = 1,
-                           ru_try = match_IntToInteger_unop (bit . fromIntegral) }
+                           ru_try = match_bitInteger }
           rule_binop str name op
            = BuiltinRule { ru_name = fsLit str, ru_fn = name, ru_nargs = 2,
                            ru_try = match_Integer_binop op }
@@ -1245,22 +1245,8 @@ match_Word64ToInteger _ id_unf id [xl]
 match_Word64ToInteger _ _ _ _ = Nothing
 
 -------------------------------------------------
-match_Integer_convert :: Num a
-                      => (DynFlags -> a -> Expr CoreBndr)
-                      -> RuleFun
-match_Integer_convert convert dflags id_unf _ [xl]
-  | Just (LitInteger x _) <- exprIsLiteral_maybe id_unf xl
-  = Just (convert dflags (fromInteger x))
-match_Integer_convert _ _ _ _ _ = Nothing
-
-match_Integer_unop :: (Integer -> Integer) -> RuleFun
-match_Integer_unop unop _ id_unf _ [xl]
-  | Just (LitInteger x i) <- exprIsLiteral_maybe id_unf xl
-  = Just (Lit (LitInteger (unop x) i))
-match_Integer_unop _ _ _ _ _ = Nothing
-
 {- Note [Rewriting bitInteger]
-
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 For most types the bitInteger operation can be implemented in terms of shifts.
 The integer-gmp package, however, can do substantially better than this if
 allowed to provide its own implementation. However, in so doing it previously lost
@@ -1275,6 +1261,40 @@ should expect some funniness given that they will have at very least ignored a
 warning in this case.
 -}
 
+match_bitInteger :: RuleFun
+-- Just for GHC.Integer.Type.bitInteger :: Int# -> Integer
+match_bitInteger dflags id_unf fn [arg]
+  | Just (MachInt x) <- exprIsLiteral_maybe id_unf arg
+  , x >= 0
+  , x <= (wordSizeInBits dflags - 1)
+    -- Make sure x is small enough to yield a decently small iteger
+    -- Attempting to construct the Integer for
+    --    (bitInteger 9223372036854775807#)
+    -- would be a bad idea (Trac #14959)
+  , let x_int = fromIntegral x :: Int
+  = case splitFunTy_maybe (idType fn) of
+    Just (_, integerTy)
+      -> Just (Lit (LitInteger (bit x_int) integerTy))
+    _ -> panic "match_IntToInteger_unop: Id has the wrong type"
+
+match_bitInteger _ _ _ _ = Nothing
+
+
+-------------------------------------------------
+match_Integer_convert :: Num a
+                      => (DynFlags -> a -> Expr CoreBndr)
+                      -> RuleFun
+match_Integer_convert convert dflags id_unf _ [xl]
+  | Just (LitInteger x _) <- exprIsLiteral_maybe id_unf xl
+  = Just (convert dflags (fromInteger x))
+match_Integer_convert _ _ _ _ _ = Nothing
+
+match_Integer_unop :: (Integer -> Integer) -> RuleFun
+match_Integer_unop unop _ id_unf _ [xl]
+  | Just (LitInteger x i) <- exprIsLiteral_maybe id_unf xl
+  = Just (Lit (LitInteger (unop x) i))
+match_Integer_unop _ _ _ _ _ = Nothing
+
 match_IntToInteger_unop :: (Integer -> Integer) -> RuleFun
 match_IntToInteger_unop unop _ id_unf fn [xl]
   | Just (MachInt x) <- exprIsLiteral_maybe id_unf xl
diff --git a/testsuite/tests/simplCore/should_compile/T14959.hs b/testsuite/tests/simplCore/should_compile/T14959.hs
new file mode 100644
index 0000000..692dfdd
--- /dev/null
+++ b/testsuite/tests/simplCore/should_compile/T14959.hs
@@ -0,0 +1,5 @@
+module T14959 where
+
+import Data.Bits (setBit)
+
+f = foldl setBit 0 [x | (x,_) <- zip [0..] [1]] :: Integer
diff --git a/testsuite/tests/simplCore/should_compile/all.T b/testsuite/tests/simplCore/should_compile/all.T
index c9af682..e68f49c 100644
--- a/testsuite/tests/simplCore/should_compile/all.T
+++ b/testsuite/tests/simplCore/should_compile/all.T
@@ -294,3 +294,4 @@ test('T14152', [ only_ways(['optasm']), check_errmsg(r'dead code') ], compile, [
 test('T14152a', [ only_ways(['optasm']), check_errmsg(r'dead code') ], compile, ['-fno-exitification -ddump-simpl'])
 test('T13990', normal, compile, ['-dcore-lint -O'])
 test('T14650', normal, compile, ['-O2'])
+test('T14959', normal, compile, ['-O'])


From git at git.haskell.org  Mon Mar 26 05:30:33 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 26 Mar 2018 05:30:33 +0000 (UTC)
Subject: [commit: ghc] ghc-8.4: Fix seq# case of exprOkForSpeculation (ac1ade1)
Message-ID: <20180326053033.42DC03A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : ghc-8.4
Link       : http://ghc.haskell.org/trac/ghc/changeset/ac1ade1ad25f145ab27219c4fb8366e982658873/ghc

>---------------------------------------------------------------

commit ac1ade1ad25f145ab27219c4fb8366e982658873
Author: Simon Peyton Jones <simonpj at microsoft.com>
Date:   Tue Mar 20 16:30:01 2018 +0000

    Fix seq# case of exprOkForSpeculation
    
    This subtle patch fixes Trac #5129 (again; comment:20
    and following).
    
    I took the opportunity to document seq# properly; see
    Note [seq# magic] in PrelRules, and Note [seq# and expr_ok]
    in CoreUtils.
    
    (cherry picked from commit abaf43d9d88d6fdf7345b936a571d17cfe1fa140)


>---------------------------------------------------------------

ac1ade1ad25f145ab27219c4fb8366e982658873
 compiler/codeGen/StgCmmExpr.hs           | 15 ++++++----
 compiler/coreSyn/CoreUtils.hs            | 24 ++++++++++++++-
 compiler/prelude/PrelRules.hs            | 51 +++++++++++++++++++++++++++++++-
 compiler/prelude/primops.txt.pp          |  8 +----
 testsuite/tests/codeGen/should_run/all.T |  8 ++++-
 5 files changed, 90 insertions(+), 16 deletions(-)

diff --git a/compiler/codeGen/StgCmmExpr.hs b/compiler/codeGen/StgCmmExpr.hs
index 3fcc935..aaff6c1 100644
--- a/compiler/codeGen/StgCmmExpr.hs
+++ b/compiler/codeGen/StgCmmExpr.hs
@@ -61,7 +61,8 @@ cgExpr  :: StgExpr -> FCode ReturnKind
 
 cgExpr (StgApp fun args)     = cgIdApp fun args
 
-{- seq# a s ==> a -}
+-- seq# a s ==> a
+-- See Note [seq# magic] in PrelRules
 cgExpr (StgOpApp (StgPrimOp SeqOp) [StgVarArg a, _] _res_ty) =
   cgIdApp a []
 
@@ -446,13 +447,14 @@ cgCase scrut@(StgApp v []) _ (PrimAlt _) _
 
 {- Note [Handle seq#]
 ~~~~~~~~~~~~~~~~~~~~~
-case seq# a s of v
-  (# s', a' #) -> e
+See Note [seq# magic] in PrelRules.
+The special case for seq# in cgCase does this:
 
+  case seq# a s of v
+    (# s', a' #) -> e
 ==>
-
-case a of v
-  (# s', a' #) -> e
+  case a of v
+    (# s', a' #) -> e
 
 (taking advantage of the fact that the return convention for (# State#, a #)
 is the same as the return convention for just 'a')
@@ -460,6 +462,7 @@ is the same as the return convention for just 'a')
 
 cgCase (StgOpApp (StgPrimOp SeqOp) [StgVarArg a, _] _) bndr alt_type alts
   = -- Note [Handle seq#]
+    -- And see Note [seq# magic] in PrelRules
     -- Use the same return convention as vanilla 'a'.
     cgCase (StgApp a []) bndr alt_type alts
 
diff --git a/compiler/coreSyn/CoreUtils.hs b/compiler/coreSyn/CoreUtils.hs
index 821104a..7ade8f8 100644
--- a/compiler/coreSyn/CoreUtils.hs
+++ b/compiler/coreSyn/CoreUtils.hs
@@ -1400,8 +1400,11 @@ app_ok primop_ok fun args
               -- Often there is a literal divisor, and this
               -- can get rid of a thunk in an inner loop
 
+        | SeqOp <- op    -- See Note [seq# and expr_ok]
+        -> all (expr_ok primop_ok) args
+
         | otherwise
-        -> primop_ok op     -- Check the primop itself
+        -> primop_ok op  -- Check the primop itself
         && and (zipWith arg_ok arg_tys args)  -- Check the arguments
 
       _other -> isUnliftedType (idType fun)          -- c.f. the Var case of exprIsHNF
@@ -1558,6 +1561,25 @@ See also Note [dataToTag#] in primops.txt.pp.
 
 Bottom line:
   * in exprOkForSpeculation we simply ignore all lifted arguments.
+  * except see Note [seq# and expr_ok] for an exception
+
+
+Note [seq# and expr_ok]
+~~~~~~~~~~~~~~~~~~~~~~~
+Recall that
+   seq# :: forall a s . a -> State# s -> (# State# s, a #)
+must always evaluate its first argument.  So it's really a
+counter-example to Note [Primops with lifted arguments]. In
+the case of seq# we must check the argument to seq#.  Remember
+item (d) of the specification of exprOkForSpeculation:
+
+  -- Precisely, it returns @True@ iff:
+  --  a) The expression guarantees to terminate,
+         ...
+  --  d) without throwing a Haskell exception
+
+The lack of this special case caused Trac #5129 to go bad again.
+See comment:24 and following
 
 
 ************************************************************************
diff --git a/compiler/prelude/PrelRules.hs b/compiler/prelude/PrelRules.hs
index 867c12f..dca6ff0 100644
--- a/compiler/prelude/PrelRules.hs
+++ b/compiler/prelude/PrelRules.hs
@@ -929,7 +929,56 @@ dataToTagRule = a `mplus` b
 ************************************************************************
 -}
 
--- seq# :: forall a s . a -> State# s -> (# State# s, a #)
+{- Note [seq# magic]
+~~~~~~~~~~~~~~~~~~~~
+The primop
+   seq# :: forall a s . a -> State# s -> (# State# s, a #)
+
+is /not/ the same as the Prelude function seq :: a -> b -> b
+as you can see from its type.  In fact, seq# is the implementation
+mechanism for 'evaluate'
+
+   evaluate :: a -> IO a
+   evaluate a = IO $ \s -> seq# a s
+
+The semantics of seq# is
+  * evaluate its first argument
+  * and return it
+
+Things to note
+
+* Why do we need a primop at all?  That is, instead of
+      case seq# x s of (# x, s #) -> blah
+  why not instead say this?
+      case x of { DEFAULT -> blah)
+
+  Reason (see Trac #5129): if we saw
+    catch# (\s -> case x of { DEFAULT -> raiseIO# exn s }) handler
+
+  then we'd drop the 'case x' because the body of the case is bottom
+  anyway. But we don't want to do that; the whole /point/ of
+  seq#/evaluate is to evaluate 'x' first in the IO monad.
+
+  In short, we /always/ evaluate the first argument and never
+  just discard it.
+
+* Why return the value?  So that we can control sharing of seq'd
+  values: in
+     let x = e in x `seq` ... x ...
+  We don't want to inline x, so better to represent it as
+       let x = e in case seq# x RW of (# _, x' #) -> ... x' ...
+  also it matches the type of rseq in the Eval monad.
+
+Implementing seq#.  The compiler has magic for SeqOp in
+
+- PrelRules.seqRule: eliminate (seq# <whnf> s)
+
+- StgCmmExpr.cgExpr, and cgCase: special case for seq#
+
+- CoreUtils.exprOkForSpeculation;
+  see Note [seq# and expr_ok] in CoreUtils
+-}
+
 seqRule :: RuleM CoreExpr
 seqRule = do
   [Type ty_a, Type ty_s, a, s] <- getArgs
diff --git a/compiler/prelude/primops.txt.pp b/compiler/prelude/primops.txt.pp
index b13123c..44e2f78 100644
--- a/compiler/prelude/primops.txt.pp
+++ b/compiler/prelude/primops.txt.pp
@@ -2698,13 +2698,7 @@ primop SparkOp "spark#" GenPrimOp
 
 primop SeqOp "seq#" GenPrimOp
    a -> State# s -> (# State# s, a #)
-
-   -- why return the value?  So that we can control sharing of seq'd
-   -- values: in
-   --    let x = e in x `seq` ... x ...
-   -- we don't want to inline x, so better to represent it as
-   --    let x = e in case seq# x RW of (# _, x' #) -> ... x' ...
-   -- also it matches the type of rseq in the Eval monad.
+   -- See Note [seq# magic] in PrelRules
 
 primop GetSparkOp "getSpark#" GenPrimOp
    State# s -> (# State# s, Int#, a #)
diff --git a/testsuite/tests/codeGen/should_run/all.T b/testsuite/tests/codeGen/should_run/all.T
index 9403c4b..55386e4 100644
--- a/testsuite/tests/codeGen/should_run/all.T
+++ b/testsuite/tests/codeGen/should_run/all.T
@@ -90,7 +90,13 @@ test('T3677', extra_run_opts('+RTS -K8k -RTS'), compile_and_run, [''])
 test('T4441', normal, compile_and_run, [''])
 test('T5149', omit_ways(['ghci']), multi_compile_and_run,
                  ['T5149', [('T5149_cmm.cmm', '')], ''])
-test('T5129', normal, compile_and_run, [''])
+
+test('T5129',
+     # The bug is in simplifier when run with -O1 and above, so only run it
+     # optimised, using any backend.
+     only_ways(['optasm']),
+     compile_and_run, [''])
+
 test('T5626', exit_code(1), compile_and_run, [''])
 test('T5747', when(arch('i386'), extra_hc_opts('-msse2')), compile_and_run, ['-O2'])
 test('T5785', normal, compile_and_run, [''])


From git at git.haskell.org  Mon Mar 26 05:30:53 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 26 Mar 2018 05:30:53 +0000 (UTC)
Subject: [commit: ghc] ghc-8.4: UnboxedTuples can't be used as constraints
 (43f63a6)
Message-ID: <20180326053053.B80B43A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : ghc-8.4
Link       : http://ghc.haskell.org/trac/ghc/changeset/43f63a6b07b183490f17f37d88aa68d00bf49445/ghc

>---------------------------------------------------------------

commit 43f63a6b07b183490f17f37d88aa68d00bf49445
Author: HE, Tao <sighingnow at gmail.com>
Date:   Wed Jan 31 21:40:03 2018 -0500

    UnboxedTuples can't be used as constraints
    
    Fixes #14740.
    
    Test Plan: make test TEST="14740"
    
    Reviewers: bgamari, simonpj
    
    Reviewed By: simonpj
    
    Subscribers: simonpj, rwbarton, thomie, carter
    
    GHC Trac Issues: #14740
    
    Differential Revision: https://phabricator.haskell.org/D4359
    
    (cherry picked from commit ced9fbd3913e1316498961bc389bfb1e141221a1)


>---------------------------------------------------------------

43f63a6b07b183490f17f37d88aa68d00bf49445
 compiler/parser/RdrHsSyn.hs                      | 13 ++++++++++++-
 testsuite/tests/parser/should_fail/T14740.hs     |  6 ++++++
 testsuite/tests/parser/should_fail/T14740.stderr |  4 ++++
 testsuite/tests/parser/should_fail/all.T         |  1 +
 4 files changed, 23 insertions(+), 1 deletion(-)

diff --git a/compiler/parser/RdrHsSyn.hs b/compiler/parser/RdrHsSyn.hs
index 119c5c6..c71841a 100644
--- a/compiler/parser/RdrHsSyn.hs
+++ b/compiler/parser/RdrHsSyn.hs
@@ -779,11 +779,22 @@ checkTyClHdr is_cls ty
       = parseErrorSDoc l (text "Malformed head of type or class declaration:"
                           <+> ppr ty)
 
+-- | Validate the context constraints and break up a context into a list
+-- of predicates.
+--
+-- @
+--     (Eq a, Ord b)        -->  [Eq a, Ord b]
+--     Eq a                 -->  [Eq a]
+--     (Eq a)               -->  [Eq a]
+--     (((Eq a)))           -->  [Eq a]
+-- @
 checkContext :: LHsType GhcPs -> P ([AddAnn],LHsContext GhcPs)
 checkContext (L l orig_t)
   = check [] (L l orig_t)
  where
-  check anns (L lp (HsTupleTy _ ts))   -- (Eq a, Ord b) shows up as a tuple type
+  check anns (L lp (HsTupleTy HsBoxedOrConstraintTuple ts))
+    -- (Eq a, Ord b) shows up as a tuple type. Only boxed tuples can
+    -- be used as context constraints.
     = return (anns ++ mkParensApiAnn lp,L l ts)                -- Ditto ()
 
     -- don't let HsAppsTy get in the way
diff --git a/testsuite/tests/parser/should_fail/T14740.hs b/testsuite/tests/parser/should_fail/T14740.hs
new file mode 100644
index 0000000..b56687f
--- /dev/null
+++ b/testsuite/tests/parser/should_fail/T14740.hs
@@ -0,0 +1,6 @@
+{-# LANGUAGE UnboxedTuples #-}
+
+module T14740 where
+
+x :: ((##)) => ()
+x = ()
diff --git a/testsuite/tests/parser/should_fail/T14740.stderr b/testsuite/tests/parser/should_fail/T14740.stderr
new file mode 100644
index 0000000..8827873
--- /dev/null
+++ b/testsuite/tests/parser/should_fail/T14740.stderr
@@ -0,0 +1,4 @@
+
+T14740.hs:5:7:
+     Expecting a lifted type, but ‘(# #)’ is unlifted
+     In the type signature: x :: ((# #)) => ()
diff --git a/testsuite/tests/parser/should_fail/all.T b/testsuite/tests/parser/should_fail/all.T
index 503cab3..28c586e 100644
--- a/testsuite/tests/parser/should_fail/all.T
+++ b/testsuite/tests/parser/should_fail/all.T
@@ -103,3 +103,4 @@ test('T8501b', normal, compile_fail, [''])
 test('T8501c', normal, compile_fail, [''])
 test('T12610', normal, compile_fail, [''])
 test('InfixAppPatErr', normal, compile_fail, [''])
+test('T14740', normal, compile_fail, [''])


From git at git.haskell.org  Mon Mar 26 05:30:43 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 26 Mar 2018 05:30:43 +0000 (UTC)
Subject: [commit: ghc] ghc-8.4: Fix #14934 by including axSub0R in
 typeNatCoAxiomRules (e04aaf7)
Message-ID: <20180326053043.99B603A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : ghc-8.4
Link       : http://ghc.haskell.org/trac/ghc/changeset/e04aaf75d97e53a24c381b98d58658ba3105cacb/ghc

>---------------------------------------------------------------

commit e04aaf75d97e53a24c381b98d58658ba3105cacb
Author: Ryan Scott <ryan.gl.scott at gmail.com>
Date:   Mon Mar 19 12:05:36 2018 -0400

    Fix #14934 by including axSub0R in typeNatCoAxiomRules
    
    For some reason, `axSub0R` was left out of `typeNatCoAxiomRules` in
    `TcTypeNats`, which led to disaster when trying to look up `Sub0R` from
    an interface file, as demonstrated in #14934.
    
    The fix is simple—just add `axSub0R` to that list. To help prevent
    an issue like this happening in the future, I added a
    `Note [Adding built-in type families]` to `TcTypeNats`, which
    contains a walkthrough of all the definitions in `TcTypeNats` you
    need to update when adding a new built-in type family.
    
    Test Plan: make test TEST=T14934
    
    Reviewers: bgamari, simonpj
    
    Reviewed By: simonpj
    
    Subscribers: simonpj, rwbarton, thomie, carter
    
    GHC Trac Issues: #14934
    
    Differential Revision: https://phabricator.haskell.org/D4508
    
    (cherry picked from commit c3aea39678398fdf88166f30f0d01225a1874a32)


>---------------------------------------------------------------

e04aaf75d97e53a24c381b98d58658ba3105cacb
 compiler/typecheck/TcTypeNats.hs                   | 84 ++++++++++++++++++++++
 testsuite/tests/typecheck/should_compile/Makefile  |  5 ++
 testsuite/tests/typecheck/should_compile/T14934.hs |  9 +++
 .../should_compile/T14934a.hs}                     | 15 ++--
 testsuite/tests/typecheck/should_compile/all.T     |  2 +
 5 files changed, 109 insertions(+), 6 deletions(-)

diff --git a/compiler/typecheck/TcTypeNats.hs b/compiler/typecheck/TcTypeNats.hs
index da9b8df..3e9865c 100644
--- a/compiler/typecheck/TcTypeNats.hs
+++ b/compiler/typecheck/TcTypeNats.hs
@@ -5,6 +5,9 @@ module TcTypeNats
   , typeNatCoAxiomRules
   , BuiltInSynFamily(..)
 
+    -- If you define a new built-in type family, make sure to export its TyCon
+    -- from here as well.
+    -- See Note [Adding built-in type families]
   , typeNatAddTyCon
   , typeNatMulTyCon
   , typeNatExpTyCon
@@ -53,10 +56,86 @@ import Data.Maybe ( isJust )
 import Control.Monad ( guard )
 import Data.List  ( isPrefixOf, isSuffixOf )
 
+{-
+Note [Type-level literals]
+~~~~~~~~~~~~~~~~~~~~~~~~~~
+There are currently two forms of type-level literals: natural numbers, and
+symbols (even though this module is named TcTypeNats, it covers both).
+
+Type-level literals are supported by CoAxiomRules (conditional axioms), which
+power the built-in type families (see Note [Adding built-in type families]).
+Currently, all built-in type families are for the express purpose of supporting
+type-level literals.
+
+See also the Wiki page:
+
+    https://ghc.haskell.org/trac/ghc/wiki/TypeNats
+
+Note [Adding built-in type families]
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+There are a few steps to adding a built-in type family:
+
+* Adding a unique for the type family TyCon
+
+  These go in PrelNames. It will likely be of the form
+  @myTyFamNameKey = mkPreludeTyConUnique xyz@, where @xyz@ is a number that
+  has not been chosen before in PrelNames. There are several examples already
+  in PrelNames—see, for instance, typeNatAddTyFamNameKey.
+
+* Adding the type family TyCon itself
+
+  This goes in TcTypeNats. There are plenty of examples of how to define
+  these—see, for instance, typeNatAddTyCon.
+
+  Once your TyCon has been defined, be sure to:
+
+  - Export it from TcTypeNats. (Not doing so caused #14632.)
+  - Include it in the typeNatTyCons list, defined in TcTypeNats.
+
+* Exposing associated type family axioms
+
+  When defining the type family TyCon, you will need to define an axiom for
+  the type family in general (see, for instance, axAddDef), and perhaps other
+  auxiliary axioms for special cases of the type family (see, for instance,
+  axAdd0L and axAdd0R).
+
+  After you have defined all of these axioms, be sure to include them in the
+  typeNatCoAxiomRules list, defined in TcTypeNats.
+  (Not doing so caused #14934.)
+
+* Define the type family somewhere
+
+  Finally, you will need to define the type family somewhere, likely in @base at .
+  Currently, all of the built-in type families are defined in GHC.TypeLits or
+  GHC.TypeNats, so those are likely candidates.
+
+  Since the behavior of your built-in type family is specified in TcTypeNats,
+  you should give an open type family definition with no instances, like so:
+
+    type family MyTypeFam (m :: Nat) (n :: Nat) :: Nat
+
+  Changing the argument and result kinds as appropriate.
+
+* Update the relevant test cases
+
+  The GHC test suite will likely need to be updated after you add your built-in
+  type family. For instance:
+
+  - The T9181 test prints the :browse contents of GHC.TypeLits, so if you added
+    a test there, the expected output of T9181 will need to change.
+  - The TcTypeNatSimple and TcTypeSymbolSimple tests have compile-time unit
+    tests, as well as TcTypeNatSimpleRun and TcTypeSymbolSimpleRun, which have
+    runtime unit tests. Consider adding further unit tests to those if your
+    built-in type family deals with Nats or Symbols, respectively.
+-}
+
 {-------------------------------------------------------------------------------
 Built-in type constructors for functions on type-level nats
 -}
 
+-- The list of built-in type family TyCons that GHC uses.
+-- If you define a built-in type family, make sure to add it to this list.
+-- See Note [Adding built-in type families]
 typeNatTyCons :: [TyCon]
 typeNatTyCons =
   [ typeNatAddTyCon
@@ -266,6 +345,7 @@ Built-in rules axioms
 
 -- If you add additional rules, please remember to add them to
 -- `typeNatCoAxiomRules` also.
+-- See Note [Adding built-in type families]
 axAddDef
   , axMulDef
   , axExpDef
@@ -375,6 +455,9 @@ axAppendSymbol0R  = mkAxiom1 "Concat0R"
 axAppendSymbol0L  = mkAxiom1 "Concat0L"
             $ \(Pair s t) -> (s `appendSymbol` mkStrLitTy nilFS) === t
 
+-- The list of built-in type family axioms that GHC uses.
+-- If you define new axioms, make sure to include them in this list.
+-- See Note [Adding built-in type families]
 typeNatCoAxiomRules :: Map.Map FastString CoAxiomRule
 typeNatCoAxiomRules = Map.fromList $ map (\x -> (coaxrName x, x))
   [ axAddDef
@@ -398,6 +481,7 @@ typeNatCoAxiomRules = Map.fromList $ map (\x -> (coaxrName x, x))
   , axCmpSymbolRefl
   , axLeq0L
   , axSubDef
+  , axSub0R
   , axAppendSymbol0R
   , axAppendSymbol0L
   , axDivDef
diff --git a/testsuite/tests/typecheck/should_compile/Makefile b/testsuite/tests/typecheck/should_compile/Makefile
index a7780ef..1bf561a 100644
--- a/testsuite/tests/typecheck/should_compile/Makefile
+++ b/testsuite/tests/typecheck/should_compile/Makefile
@@ -66,3 +66,8 @@ T13585:
 	'$(TEST_HC)' $(TEST_HC_OPTS) -c T13585a.hs -O
 	'$(TEST_HC)' $(TEST_HC_OPTS) -c T13585b.hs -O
 	'$(TEST_HC)' $(TEST_HC_OPTS) -c T13585.hs  -O
+
+T14934:
+	$(RM) -f T14934a.o T14934a.hi T14934.o T14934.hi
+	'$(TEST_HC)' $(TEST_HC_OPTS) -c T14934a.hs -O
+	'$(TEST_HC)' $(TEST_HC_OPTS) -c T14934.hs  -O
diff --git a/testsuite/tests/typecheck/should_compile/T14934.hs b/testsuite/tests/typecheck/should_compile/T14934.hs
new file mode 100644
index 0000000..581e931
--- /dev/null
+++ b/testsuite/tests/typecheck/should_compile/T14934.hs
@@ -0,0 +1,9 @@
+{-# LANGUAGE DataKinds #-}
+{-# LANGUAGE TypeOperators #-}
+module T14934 where
+
+import T14934a
+import GHC.TypeLits
+
+g :: Foo (1 - 0)
+g = f MkFoo1
diff --git a/testsuite/tests/polykinds/T10134a.hs b/testsuite/tests/typecheck/should_compile/T14934a.hs
similarity index 53%
copy from testsuite/tests/polykinds/T10134a.hs
copy to testsuite/tests/typecheck/should_compile/T14934a.hs
index 0d84d56..3ba59ff 100644
--- a/testsuite/tests/polykinds/T10134a.hs
+++ b/testsuite/tests/typecheck/should_compile/T14934a.hs
@@ -1,11 +1,14 @@
-{-# LANGUAGE KindSignatures #-}
-{-# LANGUAGE GADTs #-}
 {-# LANGUAGE DataKinds #-}
+{-# LANGUAGE GADTs #-}
+{-# LANGUAGE KindSignatures #-}
 {-# LANGUAGE TypeOperators #-}
-module T10134a where
+module T14934a where
 
 import GHC.TypeLits
 
-data Vec :: Nat -> * -> * where
-  Nil  :: Vec 0 a
-  (:>) :: a -> Vec n a -> Vec (n + 1) a
+data Foo :: Nat -> * where
+  MkFoo0 :: Foo 0
+  MkFoo1 :: Foo 1
+
+f :: Foo (1 - 0) -> Foo 1
+f x = x
diff --git a/testsuite/tests/typecheck/should_compile/all.T b/testsuite/tests/typecheck/should_compile/all.T
index f38a1ff..1ea388c 100644
--- a/testsuite/tests/typecheck/should_compile/all.T
+++ b/testsuite/tests/typecheck/should_compile/all.T
@@ -593,3 +593,5 @@ test('T14273', normal, compile, ['-fdefer-type-errors -fno-max-valid-substitutio
 test('T14732', normal, compile, [''])
 test('T14763', normal, compile, [''])
 test('T14811', normal, compile, [''])
+test('T14934', [extra_files(['T14934.hs', 'T14934a.hs'])], run_command,
+               ['$MAKE -s --no-print-directory T14934'])


From git at git.haskell.org  Mon Mar 26 06:41:48 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 26 Mar 2018 06:41:48 +0000 (UTC)
Subject: [commit: ghc] master: Add a job running on Fedora (d152dab)
Message-ID: <20180326064148.24F563A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/d152dab909a13504ebe09884a1ff329ddb796398/ghc

>---------------------------------------------------------------

commit d152dab909a13504ebe09884a1ff329ddb796398
Author: mrkkrp <markkarpov92 at gmail.com>
Date:   Wed Mar 21 22:11:04 2018 +0700

    Add a job running on Fedora


>---------------------------------------------------------------

d152dab909a13504ebe09884a1ff329ddb796398
 .circleci/config.yml                            | 19 ++++++++++++++++++
 .circleci/images/x86_64-linux-fedora/Dockerfile | 26 +++++++++++++++++++++++++
 2 files changed, 45 insertions(+)

diff --git a/.circleci/config.yml b/.circleci/config.yml
index 2868f8d..182a66b 100644
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -230,6 +230,24 @@ jobs:
       - *collectartifacts
       - *storeartifacts
 
+  "validate-x86_64-fedora":
+    resource_class: xlarge
+    docker:
+      - image: ghcci/x86_64-linux-fedora:0.0.2
+    environment:
+      <<: *buildenv
+    steps:
+      - checkout
+      - *prepare
+      - *submodules
+      - *boot
+      - *configure_unix
+      - *make
+      - *test
+      - *bindist
+      - *collectartifacts
+      - *storeartifacts
+
 workflows:
   version: 2
   validate:
@@ -241,6 +259,7 @@ workflows:
     - validate-x86_64-linux-llvm
     - validate-i386-linux
     - validate-hadrian-x86_64-linux
+    - validate-x86_64-fedora
 
   nightly:
     triggers:
diff --git a/.circleci/images/x86_64-linux-fedora/Dockerfile b/.circleci/images/x86_64-linux-fedora/Dockerfile
new file mode 100644
index 0000000..066e84f
--- /dev/null
+++ b/.circleci/images/x86_64-linux-fedora/Dockerfile
@@ -0,0 +1,26 @@
+FROM fedora:27
+
+ENV LANG C.UTF-8
+
+RUN dnf -y install coreutils binutils which git make automake autoconf gcc perl python3 texinfo xz lbzip2 patch openssh-clients sudo curl zlib-devel sqlite ncurses-compat-libs gmp-devel ncurses-devel gcc-c++ findutils
+
+# Install GHC and cabal
+RUN cd /tmp && curl https://downloads.haskell.org/~ghc/8.2.2/ghc-8.2.2-x86_64-deb8-linux.tar.xz | tar -Jx
+RUN cd /tmp/ghc-8.2.2 && ./configure --prefix=/opt/ghc/8.2.2
+RUN cd /tmp/ghc-8.2.2 && make install
+RUN mkdir -p /opt/cabal/bin
+RUN cd /opt/cabal/bin && curl https://www.haskell.org/cabal/release/cabal-install-2.0.0.1/cabal-install-2.0.0.1-x86_64-unknown-linux.tar.gz | tar -zx
+ENV PATH /opt/ghc/8.2.2/bin:/opt/cabal/bin:$PATH
+
+# Create a normal user.
+RUN adduser ghc --comment "GHC builds"
+RUN echo "ghc ALL = NOPASSWD : ALL" > /etc/sudoers.d/ghc
+USER ghc
+WORKDIR /home/ghc/
+
+# Install Alex, Happy, and HsColor with Cabal
+RUN cabal update
+RUN cabal install alex happy hscolour
+ENV PATH /home/ghc/.cabal/bin:$PATH
+
+CMD ["bash"]


From git at git.haskell.org  Mon Mar 26 06:46:26 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 26 Mar 2018 06:46:26 +0000 (UTC)
Subject: [commit: ghc] master: circleci: Bump Hackage index state (60e29dc)
Message-ID: <20180326064626.B1DC03A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/60e29dc2611f5c1a01cfd9a870841927847a7b74/ghc

>---------------------------------------------------------------

commit 60e29dc2611f5c1a01cfd9a870841927847a7b74
Author: Ben Gamari <ben at smart-cactus.org>
Date:   Mon Mar 26 02:45:53 2018 -0400

    circleci: Bump Hackage index state


>---------------------------------------------------------------

60e29dc2611f5c1a01cfd9a870841927847a7b74
 .circleci/prepare-system.sh | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/.circleci/prepare-system.sh b/.circleci/prepare-system.sh
index 61396c8..df0da01 100755
--- a/.circleci/prepare-system.sh
+++ b/.circleci/prepare-system.sh
@@ -9,7 +9,7 @@ fail() {
 
 echo 'BUILD_SPHINX_HTML = NO' > mk/validate.mk
 echo 'BUILD_SPHINX_PDF = NO' >> mk/validate.mk
-hackage_index_state="@1511758800"
+hackage_index_state="@1522046735"
 
 cat > mk/build.mk <<EOF
 V=1


From git at git.haskell.org  Mon Mar 26 11:47:00 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 26 Mar 2018 11:47:00 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4395-new: Fix huge performance regression
 (5d1a707)
Message-ID: <20180326114700.4A3B33A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/tdammers/D4395-new
Link       : http://ghc.haskell.org/trac/ghc/changeset/5d1a707c6c78dedc915604aec702d07c4bc741c5/ghc

>---------------------------------------------------------------

commit 5d1a707c6c78dedc915604aec702d07c4bc741c5
Author: Tobias Dammers <tdammers at gmail.com>
Date:   Mon Mar 26 13:44:56 2018 +0200

    Fix huge performance regression
    
    Previous version caused a 10x increase in execution time for the
    infamous Grammar.hs test case from #14683; this patch gets us back on
    par.


>---------------------------------------------------------------

5d1a707c6c78dedc915604aec702d07c4bc741c5
 compiler/simplCore/Simplify.hs | 102 +++++++++++++++++++----------------------
 1 file changed, 46 insertions(+), 56 deletions(-)

diff --git a/compiler/simplCore/Simplify.hs b/compiler/simplCore/Simplify.hs
index b2444e5..5e5d836 100644
--- a/compiler/simplCore/Simplify.hs
+++ b/compiler/simplCore/Simplify.hs
@@ -1215,62 +1215,52 @@ simplCast env body co0 cont0
   where
         -- If the first parameter is Nothing, then simplifying revealed a
         -- reflexive coercion. Omit.
-       addCoerce0 :: Maybe OutCoercion -> SimplCont -> SimplM SimplCont
-       addCoerce0 Nothing   cont = return cont
-       addCoerce0 (Just co) cont = addCoerce co cont
-
-       addCoerce :: OutCoercion -> SimplCont -> SimplM SimplCont
-       addCoerce co cont  -- just skip reflexive casts
-         | isReflexiveCo co = {-#SCC "addCoerce-reflexive" #-}
-                              return cont
-                -- It's worth checking isReflexiveCo.
-                -- For example, in the initial form of a worker
-                -- we may find  (coerce T (coerce S (\x.e))) y
-                -- and we'd like it to simplify to e[y/x] in one round
-                -- of simplification
-
-       addCoerce co1 (CastIt co2 cont)
-         = addCoerce (mkTransCo co1 co2) cont
-
-       addCoerce co cont@(ApplyToTy { sc_arg_ty = arg_ty, sc_cont = tail })
-         | Just (arg_ty', m_co') <- pushCoTyArg co arg_ty
-         = case m_co' of
-             Just co' -> do { tail' <- addCoerce co' tail
-                            ; return (cont { sc_arg_ty = arg_ty', sc_cont = tail' }) }
-             Nothing  -> return cont
-
-       addCoerce co cont@(ApplyToVal { sc_arg = arg, sc_env = arg_se
-                                , sc_dup = dup, sc_cont = tail })
-         | Just (co1, m_co2) <- pushCoValArg co
-         , Pair _ new_ty <- coercionKind co1
-         , not (isTypeLevPoly new_ty)  -- without this check, we get a lev-poly arg
-                                       -- See Note [Levity polymorphism invariants] in CoreSyn
-                                       -- test: typecheck/should_run/EtaExpandLevPoly
-         = do { tail' <- addCoerce0 m_co2 tail
-              ; if isReflCo co1
-                then return (cont { sc_cont = tail' })
-                     -- Avoid simplifying if possible;
-                     -- See Note [Avoiding exponential behaviour]
-                else do
-              { (dup', arg_se', arg') <- simplArg env dup arg_se arg
-                   -- When we build the ApplyTo we can't mix the OutCoercion
-                   -- 'co' with the InExpr 'arg', so we simplify
-                   -- to make it all consistent.  It's a bit messy.
-                   -- But it isn't a common case.
-                   -- Example of use: Trac #995
-              ; return (ApplyToVal { sc_arg  = mkCast arg' co1
-                                   , sc_env  = arg_se'
-                                   , sc_dup  = dup'
-                                   , sc_cont = tail' }) } }
-
-       addCoerce co cont
-         | isReflexiveCo co = return cont
-         | otherwise        = return (CastIt co cont)
-                -- It's worth checking isReflexiveCo.
-                -- For example, in the initial form of a worker
-                -- we may find  (coerce T (coerce S (\x.e))) y
-                -- and we'd like it to simplify to e[y/x] in one round
-                -- of simplification
+        addCoerce0 :: Maybe OutCoercion -> SimplCont -> SimplM SimplCont
+        addCoerce0 Nothing   cont = return cont
+        addCoerce0 (Just co) cont = addCoerce co cont
+
+        addCoerce :: OutCoercion -> SimplCont -> SimplM SimplCont
+
+        addCoerce co1 (CastIt co2 cont)
+          = addCoerce (mkTransCo co1 co2) cont
+
+        addCoerce co cont@(ApplyToTy { sc_arg_ty = arg_ty, sc_cont = tail })
+          | Just (arg_ty', m_co') <- pushCoTyArg co arg_ty
+          = do { tail' <- addCoerce0 m_co' tail
+               ; return (cont { sc_arg_ty = arg_ty', sc_cont = tail' }) }
+
+        addCoerce co cont@(ApplyToVal { sc_arg = arg, sc_env = arg_se
+                                 , sc_dup = dup, sc_cont = tail })
+          | Just (co1, m_co2) <- pushCoValArg co
+          , Pair _ new_ty <- coercionKind co1
+          , not (isTypeLevPoly new_ty)  -- without this check, we get a lev-poly arg
+                                        -- See Note [Levity polymorphism invariants] in CoreSyn
+                                        -- test: typecheck/should_run/EtaExpandLevPoly
+          = do { tail' <- addCoerce0 m_co2 tail
+               ; if isReflCo co1
+                 then return (cont { sc_cont = tail' })
+                      -- Avoid simplifying if possible;
+                      -- See Note [Avoiding exponential behaviour]
+                 else do
+               { (dup', arg_se', arg') <- simplArg env dup arg_se arg
+                    -- When we build the ApplyTo we can't mix the OutCoercion
+                    -- 'co' with the InExpr 'arg', so we simplify
+                    -- to make it all consistent.  It's a bit messy.
+                    -- But it isn't a common case.
+                    -- Example of use: Trac #995
+               ; return (ApplyToVal { sc_arg  = mkCast arg' co1
+                                    , sc_env  = arg_se'
+                                    , sc_dup  = dup'
+                                    , sc_cont = tail' }) } }
+
+        addCoerce co cont
+          | isReflexiveCo co = return cont
+          | otherwise        = return (CastIt co cont)
+                 -- It's worth checking isReflexiveCo.
+                 -- For example, in the initial form of a worker
+                 -- we may find  (coerce T (coerce S (\x.e))) y
+                 -- and we'd like it to simplify to e[y/x] in one round
+                 -- of simplification
 
 simplArg :: SimplEnv -> DupFlag -> StaticEnv -> CoreExpr
          -> SimplM (DupFlag, StaticEnv, OutExpr)


From git at git.haskell.org  Mon Mar 26 19:17:11 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 26 Mar 2018 19:17:11 +0000 (UTC)
Subject: [commit: ghc] master: rts,
 base: Refactor stats.c to improve --machine-readable report (f0b258b)
Message-ID: <20180326191711.8421D3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/f0b258bc7e2d4ef32a20c61b7285a21f7680660e/ghc

>---------------------------------------------------------------

commit f0b258bc7e2d4ef32a20c61b7285a21f7680660e
Author: Douglas Wilson <douglas.wilson at gmail.com>
Date:   Mon Mar 26 15:16:11 2018 -0400

    rts, base: Refactor stats.c to improve --machine-readable report
    
    There should be no change in the output of the '+RTS -s' (summary)
    report, or
    the 'RTS -t' (one-line) report.
    
    All data shown in the summary report is now shown in the machine
    readable
    report.
    
    All data in RTSStats is now shown in the machine readable report.
    
    init times are added to RTSStats and added to GHC.Stats.
    
    Example of the new output:
    ```
     [("bytes allocated", "375016384")
     ,("num_GCs", "113")
     ,("average_bytes_used", "148348")
     ,("max_bytes_used", "206552")
     ,("num_byte_usage_samples", "2")
     ,("peak_megabytes_allocated", "6")
     ,("init_cpu_seconds", "0.001642")
     ,("init_wall_seconds", "0.001027")
     ,("mut_cpu_seconds", "3.020166")
     ,("mut_wall_seconds", "0.757244")
     ,("GC_cpu_seconds", "0.037750")
     ,("GC_wall_seconds", "0.009569")
     ,("exit_cpu_seconds", "0.000890")
     ,("exit_wall_seconds", "0.002551")
     ,("total_cpu_seconds", "3.060452")
     ,("total_wall_seconds", "0.770395")
     ,("major_gcs", "2")
     ,("allocated_bytes", "375016384")
     ,("max_live_bytes", "206552")
     ,("max_large_objects_bytes", "159344")
     ,("max_compact_bytes", "0")
     ,("max_slop_bytes", "59688")
     ,("max_mem_in_use_bytes", "6291456")
     ,("cumulative_live_bytes", "296696")
     ,("copied_bytes", "541024")
     ,("par_copied_bytes", "493976")
     ,("cumulative_par_max_copied_bytes", "104104")
     ,("cumulative_par_balanced_copied_bytes", "274456")
     ,("fragmentation_bytes", "2112")
     ,("alloc_rate", "124170795")
     ,("productivity_cpu_percent", "0.986838")
     ,("productivity_wall_percent", "0.982935")
     ,("bound_task_count", "1")
     ,("sparks_count", "5836258")
     ,("sparks_converted", "237")
     ,("sparks_overflowed", "1990408")
     ,("sparks_dud ", "0")
     ,("sparks_gcd", "3455553")
     ,("sparks_fizzled", "390060")
     ,("work_balance", "0.555606")
     ,("n_capabilities", "4")
     ,("task_count", "10")
     ,("peak_worker_count", "9")
     ,("worker_count", "9")
     ,("gc_alloc_block_sync_spin", "162")
     ,("gc_alloc_block_sync_yield", "0")
     ,("gc_alloc_block_sync_spin", "162")
     ,("gc_spin_spin", "18840855")
     ,("gc_spin_yield", "10355")
     ,("mut_spin_spin", "70331392")
     ,("mut_spin_yield", "61700")
     ,("waitForGcThreads_spin", "241")
     ,("waitForGcThreads_yield", "2797")
     ,("whitehole_gc_spin", "0")
     ,("whitehole_lockClosure_spin", "0")
     ,("whitehole_lockClosure_yield", "0")
     ,("whitehole_executeMessage_spin", "0")
     ,("whitehole_threadPaused_spin", "0")
     ,("any_work", "1667")
     ,("no_work", "1662")
     ,("scav_find_work", "1026")
     ,("gen_0_collections", "111")
     ,("gen_0_par_collections", "111")
     ,("gen_0_cpu_seconds", "0.036126")
     ,("gen_0_wall_seconds", "0.036126")
     ,("gen_0_max_pause_seconds", "0.036126")
     ,("gen_0_avg_pause_seconds", "0.000081")
     ,("gen_0_sync_spin", "21")
     ,("gen_0_sync_yield", "0")
     ,("gen_1_collections", "2")
     ,("gen_1_par_collections", "1")
     ,("gen_1_cpu_seconds", "0.001624")
     ,("gen_1_wall_seconds", "0.001624")
     ,("gen_1_max_pause_seconds", "0.001624")
     ,("gen_1_avg_pause_seconds", "0.000272")
     ,("gen_1_sync_spin", "3")
     ,("gen_1_sync_yield", "0")
     ]
    ```
    
    Test Plan: Ensure that one-line and summary reports are unchanged.
    
    Reviewers: erikd, simonmar, hvr
    
    Subscribers: duog, carter, thomie, rwbarton
    
    GHC Trac Issues: #14660
    
    Differential Revision: https://phabricator.haskell.org/D4529


>---------------------------------------------------------------

f0b258bc7e2d4ef32a20c61b7285a21f7680660e
 includes/RtsAPI.h            |  34 +-
 libraries/base/GHC/Stats.hsc |   8 +
 rts/Stats.c                  | 921 +++++++++++++++++++++++++++++--------------
 rts/Stats.h                  |  45 +++
 4 files changed, 691 insertions(+), 317 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc f0b258bc7e2d4ef32a20c61b7285a21f7680660e

From git at git.haskell.org  Mon Mar 26 20:33:07 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 26 Mar 2018 20:33:07 +0000 (UTC)
Subject: [commit: ghc] master: Make it evident in types that StgLam can't have
 empty args (41c1558)
Message-ID: <20180326203307.E0D673A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/41c155876c9e8137ff9b9f9f9a12c4a78a44bc70/ghc

>---------------------------------------------------------------

commit 41c155876c9e8137ff9b9f9f9a12c4a78a44bc70
Author: Ömer Sinan Ağacan <omeragacan at gmail.com>
Date:   Mon Mar 26 23:15:32 2018 +0300

    Make it evident in types that StgLam can't have empty args
    
    StgLam can't have empty arguments. Reflect this in types. An assertion
    can now be deleted.
    
    Reviewers: bgamari
    
    Reviewed By: bgamari
    
    Subscribers: rwbarton, thomie, carter
    
    Differential Revision: https://phabricator.haskell.org/D4484


>---------------------------------------------------------------

41c155876c9e8137ff9b9f9f9a12c4a78a44bc70
 compiler/stgSyn/CoreToStg.hs | 13 +++++++------
 compiler/stgSyn/StgSyn.hs    |  6 ++++--
 2 files changed, 11 insertions(+), 8 deletions(-)

diff --git a/compiler/stgSyn/CoreToStg.hs b/compiler/stgSyn/CoreToStg.hs
index cb4e7f6..3ee3ba5 100644
--- a/compiler/stgSyn/CoreToStg.hs
+++ b/compiler/stgSyn/CoreToStg.hs
@@ -49,6 +49,7 @@ import PrimOp           ( PrimCall(..) )
 import UniqFM
 import SrcLoc           ( mkGeneralSrcSpan )
 
+import Data.List.NonEmpty (nonEmpty, toList)
 import Data.Maybe    (isJust, fromMaybe)
 import Control.Monad (liftM, ap)
 
@@ -418,9 +419,10 @@ coreToStgExpr expr@(Lam _ _)
     extendVarEnvCts [ (a, LambdaBound) | a <- args' ] $ do
     (body, body_fvs) <- coreToStgExpr body
     let
-        fvs             = args' `minusFVBinders` body_fvs
-        result_expr | null args' = body
-                    | otherwise  = StgLam args' body
+        fvs         = args' `minusFVBinders` body_fvs
+        result_expr = case nonEmpty args' of
+          Nothing     -> body
+          Just args'' -> StgLam args'' body
 
     return (result_expr, fvs)
 
@@ -771,11 +773,10 @@ mkTopStgRhs :: DynFlags -> Module -> CollectedCCs
 mkTopStgRhs dflags this_mod ccs rhs_fvs bndr binder_info rhs
   | StgLam bndrs body <- rhs
   = -- StgLam can't have empty arguments, so not CAF
-    ASSERT(not (null bndrs))
     ( StgRhsClosure dontCareCCS binder_info
                     (getFVs rhs_fvs)
                     ReEntrant
-                    bndrs body
+                    (toList bndrs) body
     , ccs )
 
   | StgConApp con args _ <- unticked_rhs
@@ -825,7 +826,7 @@ mkStgRhs rhs_fvs bndr binder_info rhs
   = StgRhsClosure currentCCS binder_info
                   (getFVs rhs_fvs)
                   ReEntrant
-                  bndrs body
+                  (toList bndrs) body
 
   | isJoinId bndr -- must be a nullary join point
   = ASSERT(idJoinArity bndr == 0)
diff --git a/compiler/stgSyn/StgSyn.hs b/compiler/stgSyn/StgSyn.hs
index 29d5441..608a028 100644
--- a/compiler/stgSyn/StgSyn.hs
+++ b/compiler/stgSyn/StgSyn.hs
@@ -70,6 +70,8 @@ import RepType     ( typePrimRep1 )
 import Unique      ( Unique )
 import Util
 
+import Data.List.NonEmpty ( NonEmpty, toList )
+
 {-
 ************************************************************************
 *                                                                      *
@@ -221,7 +223,7 @@ finished it encodes (\x -> e) as (let f = \x -> e in f)
 -}
 
   | StgLam
-        [bndr]
+        (NonEmpty bndr)
         StgExpr    -- Body of lambda
 
 {-
@@ -721,7 +723,7 @@ pprStgExpr (StgOpApp op args _)
   = hsep [ pprStgOp op, brackets (interppSP args)]
 
 pprStgExpr (StgLam bndrs body)
-  = sep [ char '\\' <+> ppr_list (map (pprBndr LambdaBind) bndrs)
+  = sep [ char '\\' <+> ppr_list (map (pprBndr LambdaBind) (toList bndrs))
             <+> text "->",
          pprStgExpr body ]
   where ppr_list = brackets . fsep . punctuate comma


From git at git.haskell.org  Mon Mar 26 21:25:34 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 26 Mar 2018 21:25:34 +0000 (UTC)
Subject: [commit: ghc] master: Fix #12919 by making the flattener homegeneous.
 (e3dbb44)
Message-ID: <20180326212534.7C0533A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/e3dbb44f53b2f9403d20d84e27f187062755a089/ghc

>---------------------------------------------------------------

commit e3dbb44f53b2f9403d20d84e27f187062755a089
Author: Richard Eisenberg <rae at cs.brynmawr.edu>
Date:   Thu Aug 3 15:18:39 2017 -0400

    Fix #12919 by making the flattener homegeneous.
    
    This changes a key invariant of the flattener. Previously,
    flattening a type meant flattening its kind as well. But now,
    flattening is always homogeneous -- that is, the kind of the
    flattened type is the same as the kind of the input type.
    This is achieved by various wizardry in the TcFlatten.flatten_many
    function, as described in Note [flatten_many].
    
    There are several knock-on effects, including some refactoring
    in the canonicalizer to take proper advantage of the flattener's
    changed behavior. In particular, the tyvar case of can_eq_nc' no
    longer needs to take casts into account.
    
    Another effect is that flattening a tyconapp might change it
    into a casted tyconapp. This might happen if the result kind
    of the tycon contains a variable, and that variable changes
    during flattening. Because the flattener is homogeneous, it tacks
    on a cast to keep the tyconapp kind the same. However, this
    is problematic when flattening CFunEqCans, which need to have
    an uncasted tyconapp on the LHS and must remain homogeneous.
    The solution is a more involved canCFunEqCan, described in
    Note [canCFunEqCan].
    
    This patch fixes #13643 (as tested in typecheck/should_compile/T13643)
    and the panic in typecheck/should_compile/T13822 (as reported in #14024).
    Actually, there were two bugs in T13822: the first was just some
    incorrect logic in tryFill (part of the unflattener) -- also fixed
    in this patch -- and the other was the main bug fixed in this ticket.
    
    The changes in this patch exposed a long-standing flaw in OptCoercion,
    in that breaking apart an AppCo sometimes has unexpected effects on
    kinds. See new Note [EtaAppCo] in OptCoercion, which explains the
    problem and fix.
    
    Also here is a reversion of the major change in
    09bf135ace55ce2572bf4168124d631e386c64bb, affecting ctEvCoercion.
    It turns out that making the flattener homogeneous changes the
    invariants on the algorithm, making the change in that patch
    no longer necessary.
    
    This patch also fixes:
      #14038 (dependent/should_compile/T14038)
      #13910 (dependent/should_compile/T13910)
      #13938 (dependent/should_compile/T13938)
      #14441 (typecheck/should_compile/T14441)
      #14556 (dependent/should_compile/T14556)
      #14720 (dependent/should_compile/T14720)
      #14749 (typecheck/should_compile/T14749)
    
    Sadly, this patch negatively affects performance of type-family-
    heavy code. The following patch fixes these performance degradations.
    However, the performance fixes are somewhat invasive and so I've
    kept them as a separate patch, labeling this one as [skip ci] so
    that validation doesn't fail on the performance cases.


>---------------------------------------------------------------

e3dbb44f53b2f9403d20d84e27f187062755a089
 compiler/typecheck/TcCanonical.hs                  | 334 ++++++---
 compiler/typecheck/TcFlatten.hs                    | 782 ++++++++++++++-------
 compiler/typecheck/TcInteract.hs                   |  51 +-
 compiler/typecheck/TcMType.hs                      |  11 +-
 compiler/typecheck/TcRnTypes.hs                    |  15 +-
 compiler/typecheck/TcSMonad.hs                     | 100 ++-
 compiler/typecheck/TcType.hs                       |   2 +-
 compiler/types/Coercion.hs                         | 235 ++++---
 compiler/types/Coercion.hs-boot                    |   1 +
 compiler/types/OptCoercion.hs                      | 110 ++-
 compiler/types/TyCoRep.hs                          |  83 ++-
 compiler/types/Type.hs                             |  84 +--
 testsuite/tests/dependent/should_compile/T14556.hs |  38 +
 testsuite/tests/dependent/should_compile/T14720.hs |  44 ++
 testsuite/tests/dependent/should_compile/all.T     |   8 +-
 .../tests/dependent/should_fail/RAE_T32a.stderr    |  25 +-
 testsuite/tests/dependent/should_fail/all.T        |   2 +-
 .../tests/typecheck/should_compile/SplitWD.hs      |  55 ++
 testsuite/tests/typecheck/should_compile/T13643.hs |  22 +
 testsuite/tests/typecheck/should_compile/T14441.hs |  15 +
 testsuite/tests/typecheck/should_compile/T14749.hs |  27 +
 testsuite/tests/typecheck/should_compile/all.T     |   8 +-
 .../tests/typecheck/should_fail/T12373.stderr      |   8 +-
 .../tests/typecheck/should_run/Typeable1.stderr    |   3 +-
 24 files changed, 1408 insertions(+), 655 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc e3dbb44f53b2f9403d20d84e27f187062755a089

From git at git.haskell.org  Mon Mar 26 21:25:37 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 26 Mar 2018 21:25:37 +0000 (UTC)
Subject: [commit: ghc] master: Fix compilation stopper on macOS with -Werror
 (97e1f30)
Message-ID: <20180326212537.4724C3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/97e1f300e4f6aef06863d056dc7992fef6b21538/ghc

>---------------------------------------------------------------

commit 97e1f300e4f6aef06863d056dc7992fef6b21538
Author: Richard Eisenberg <rae at cs.brynmawr.edu>
Date:   Mon Mar 26 12:45:59 2018 -0400

    Fix compilation stopper on macOS with -Werror
    
    Commit 94f02547083cf6df686ea0b95fed050184c533de
    added some pragmas that allow GCC to compile GHC, but stop
    macOS's clang. This adds another counter-pragma to halp
    clang lumber along, too.
    
    Fixes #14977.


>---------------------------------------------------------------

97e1f300e4f6aef06863d056dc7992fef6b21538
 libraries/ghc-prim/cbits/atomic.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/libraries/ghc-prim/cbits/atomic.c b/libraries/ghc-prim/cbits/atomic.c
index 80d4f39..b238041 100644
--- a/libraries/ghc-prim/cbits/atomic.c
+++ b/libraries/ghc-prim/cbits/atomic.c
@@ -123,8 +123,10 @@ hs_atomic_and64(StgWord x, StgWord64 val)
 #endif
 
 // Otherwise this fails with -Werror
+#if defined(__GNUC__) && !defined(__clang__)
 #pragma GCC diagnostic push
 #pragma GCC diagnostic ignored "-Wsync-nand"
+#endif
 
 extern StgWord hs_atomic_nand8(StgWord x, StgWord val);
 StgWord


From git at git.haskell.org  Mon Mar 26 21:25:40 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Mon, 26 Mar 2018 21:25:40 +0000 (UTC)
Subject: [commit: ghc] master: Fix performance of flattener patch (#12919)
 (b47a6c3)
Message-ID: <20180326212540.250643A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/b47a6c3a6d9c5da341184824549a6a835c79de15/ghc

>---------------------------------------------------------------

commit b47a6c3a6d9c5da341184824549a6a835c79de15
Author: Alexander Vieth <aovieth at gmail.com>
Date:   Mon Mar 26 11:19:27 2018 -0400

    Fix performance of flattener patch (#12919)
    
    This patch, authored by alexvieth and reviewed at D4451,
    makes performance improvements by critically optimizing parts
    of the flattener.
    
    Summary:
    T3064, T5321FD, T5321Fun, T9872a, T9872b, T9872c all pass.
    T9872a and T9872c show improvements beyond the -5% threshold.
    T9872d fails at 10.9% increased allocations.


>---------------------------------------------------------------

b47a6c3a6d9c5da341184824549a6a835c79de15
 compiler/typecheck/TcFlatten.hs         | 499 +++++++++++++++++++++++---------
 compiler/types/CoAxiom.hs               |   2 +-
 compiler/types/Coercion.hs              |   1 -
 compiler/types/FamInstEnv.hs            |  31 +-
 compiler/types/Type.hs                  |  17 +-
 testsuite/tests/perf/compiler/all.T     |   9 +-
 testsuite/tests/polykinds/T14846.stderr |   7 +-
 7 files changed, 405 insertions(+), 161 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc b47a6c3a6d9c5da341184824549a6a835c79de15

From git at git.haskell.org  Tue Mar 27 08:29:28 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 27 Mar 2018 08:29:28 +0000 (UTC)
Subject: [commit: ghc] master: Deal with join points with RULES (a7628dc)
Message-ID: <20180327082928.212E13A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/a7628dcd2cb570fe41de247af6aa71a89177a9b9/ghc

>---------------------------------------------------------------

commit a7628dcd2cb570fe41de247af6aa71a89177a9b9
Author: Simon Peyton Jones <simonpj at microsoft.com>
Date:   Mon Mar 26 17:16:14 2018 +0100

    Deal with join points with RULES
    
    Trac #13900 showed that when we have a join point that
    has a RULE, we must push the continuation into the RHS
    of the RULE.
    
    See Note [Rules and unfolding for join points]
    
    It's hard to tickle this bug, so I have not added a regression test.


>---------------------------------------------------------------

a7628dcd2cb570fe41de247af6aa71a89177a9b9
 compiler/simplCore/SimplCore.hs |   2 +-
 compiler/simplCore/Simplify.hs  | 120 ++++++++++++++++++++++++++++------------
 2 files changed, 86 insertions(+), 36 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc a7628dcd2cb570fe41de247af6aa71a89177a9b9

From git at git.haskell.org  Tue Mar 27 08:29:30 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 27 Mar 2018 08:29:30 +0000 (UTC)
Subject: [commit: ghc] master: Minor refactor and commments (71d50db)
Message-ID: <20180327082930.DA39D3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/71d50db1f511d7aee32e6b429cdb912fcf6071b0/ghc

>---------------------------------------------------------------

commit 71d50db1f511d7aee32e6b429cdb912fcf6071b0
Author: Simon Peyton Jones <simonpj at microsoft.com>
Date:   Mon Mar 26 16:07:06 2018 +0100

    Minor refactor and commments
    
    Minor refactor and comments, following Ryan's excellent DeriveAnyClass
    bug (Trac #14932)


>---------------------------------------------------------------

71d50db1f511d7aee32e6b429cdb912fcf6071b0
 compiler/typecheck/TcDerivInfer.hs | 41 ++++++++++++++++++++++----------------
 1 file changed, 24 insertions(+), 17 deletions(-)

diff --git a/compiler/typecheck/TcDerivInfer.hs b/compiler/typecheck/TcDerivInfer.hs
index 2ea8372..ec779c5 100644
--- a/compiler/typecheck/TcDerivInfer.hs
+++ b/compiler/typecheck/TcDerivInfer.hs
@@ -638,19 +638,25 @@ simplifyDeriv pred tvs thetas
                let given_pred = substTy skol_subst given
                in newEvVar given_pred
 
-             mk_wanted_cts :: [TyVar] -> [PredOrigin] -> TcM [CtEvidence]
-             mk_wanted_cts metas_to_be wanteds
-               = do -- We instantiate metas_to_be with fresh meta type
-                    -- variables. Currently, these can only be type variables
-                    -- quantified in generic default type signatures.
-                    -- See Note [Gathering and simplifying constraints for
-                    -- DeriveAnyClass]
-                    (meta_subst, _meta_tvs) <- newMetaTyVars metas_to_be
-                    let wanted_subst = skol_subst `unionTCvSubst` meta_subst
-                        mk_wanted_ct (PredOrigin wanted o t_or_k)
-                          = newWanted o (Just t_or_k) $
-                            substTyUnchecked wanted_subst wanted
-                    mapM mk_wanted_ct wanteds
+             emit_wanted_constraints :: [TyVar] -> [PredOrigin] -> TcM ()
+             emit_wanted_constraints metas_to_be preds
+               = do { -- We instantiate metas_to_be with fresh meta type
+                      -- variables. Currently, these can only be type variables
+                      -- quantified in generic default type signatures.
+                      -- See Note [Gathering and simplifying constraints for
+                      -- DeriveAnyClass]
+                      (meta_subst, _meta_tvs) <- newMetaTyVars metas_to_be
+
+                    -- Now make a constraint for each of the instantiated predicates
+                    ; let wanted_subst = skol_subst `unionTCvSubst` meta_subst
+                          mk_wanted_ct (PredOrigin wanted orig t_or_k)
+                            = do { ev <- newWanted orig (Just t_or_k) $
+                                         substTyUnchecked wanted_subst wanted
+                                 ; return (mkNonCanonical ev) }
+                    ; cts <- mapM mk_wanted_ct preds
+
+                    -- And emit them into the monad
+                    ; emitSimples (listToCts cts) }
 
              -- Create the implications we need to solve. For stock and newtype
              -- deriving, these implication constraints will be simple class
@@ -661,14 +667,15 @@ simplifyDeriv pred tvs thetas
              mk_wanteds (ThetaOrigin { to_anyclass_skols  = ac_skols
                                      , to_anyclass_metas  = ac_metas
                                      , to_anyclass_givens = ac_givens
-                                     , to_wanted_origins  = wanteds })
+                                     , to_wanted_origins  = preds })
                = do { ac_given_evs <- mapM mk_given_ev ac_givens
                     ; (_, wanteds)
                         <- captureConstraints $
                            checkConstraints skol_info ac_skols ac_given_evs $
-                           do { cts <- mk_wanted_cts ac_metas wanteds
-                              ; emitSimples $ listToCts
-                                            $ map mkNonCanonical cts }
+                              -- The checkConstraints bumps the TcLevel, and
+                              -- wraps the wanted constraints in an implication,
+                              -- when (but only when) necessary
+                           emit_wanted_constraints ac_metas preds
                     ; pure wanteds }
 
        -- See [STEP DAC BUILD]


From git at git.haskell.org  Tue Mar 27 08:29:33 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 27 Mar 2018 08:29:33 +0000 (UTC)
Subject: [commit: ghc] master: Avoid quadratic complexity in typeKind (1fce2c3)
Message-ID: <20180327082933.9E3F43A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/1fce2c3a83f0356146f24674b79b04f66c231e9d/ghc

>---------------------------------------------------------------

commit 1fce2c3a83f0356146f24674b79b04f66c231e9d
Author: Simon Peyton Jones <simonpj at microsoft.com>
Date:   Mon Mar 26 15:54:53 2018 +0100

    Avoid quadratic complexity in typeKind
    
    I took 10 minute to fix this potential performance hole
    (Trac #14263)
    
    There are no actual bug reports against it, so no regression
    test.


>---------------------------------------------------------------

1fce2c3a83f0356146f24674b79b04f66c231e9d
 compiler/types/Type.hs | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/compiler/types/Type.hs b/compiler/types/Type.hs
index ef387b6..c274116 100644
--- a/compiler/types/Type.hs
+++ b/compiler/types/Type.hs
@@ -2296,7 +2296,7 @@ nonDetCmpTc tc1 tc2
 
 typeKind :: HasDebugCallStack => Type -> Kind
 typeKind (TyConApp tc tys)     = piResultTys (tyConKind tc) tys
-typeKind (AppTy fun arg)       = piResultTy (typeKind fun) arg
+typeKind (AppTy fun arg)       = typeKind_apps fun [arg]
 typeKind (LitTy l)             = typeLiteralKind l
 typeKind (FunTy {})            = liftedTypeKind
 typeKind (ForAllTy _ ty)       = typeKind ty
@@ -2304,6 +2304,15 @@ typeKind (TyVarTy tyvar)       = tyVarKind tyvar
 typeKind (CastTy _ty co)       = pSnd $ coercionKind co
 typeKind (CoercionTy co)       = coercionType co
 
+typeKind_apps :: HasDebugCallStack => Type -> [Type] -> Kind
+-- The sole purpose of the function is to accumulate
+-- the type arugments, so we can call piResultTys, rather than
+-- a succession of calls to piResultTy (which is asymptotically
+-- less efficient as the number of arguments increases)
+typeKind_apps (AppTy fun arg) args = typeKind_apps fun (arg:args)
+typeKind_apps fun             args = piResultTys (typeKind fun) args
+
+--------------------------
 typeLiteralKind :: TyLit -> Kind
 typeLiteralKind l =
   case l of


From git at git.haskell.org  Tue Mar 27 08:29:36 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 27 Mar 2018 08:29:36 +0000 (UTC)
Subject: [commit: ghc] master: White space only (9cc6a18)
Message-ID: <20180327082936.66FAC3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/9cc6a182fc6f6d331774f0818bba5755188328cd/ghc

>---------------------------------------------------------------

commit 9cc6a182fc6f6d331774f0818bba5755188328cd
Author: Simon Peyton Jones <simonpj at microsoft.com>
Date:   Mon Mar 26 16:09:45 2018 +0100

    White space only


>---------------------------------------------------------------

9cc6a182fc6f6d331774f0818bba5755188328cd
 compiler/simplCore/OccurAnal.hs | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/compiler/simplCore/OccurAnal.hs b/compiler/simplCore/OccurAnal.hs
index b7fc977..b1d2403 100644
--- a/compiler/simplCore/OccurAnal.hs
+++ b/compiler/simplCore/OccurAnal.hs
@@ -2724,14 +2724,18 @@ decideJoinPointHood NotTopLevel usage bndrs
     ok bndr
       | -- Invariant 1: Only tail calls, all same join arity
         AlwaysTailCalled arity <- tailCallInfo (lookupDetails usage bndr)
+
       , -- Invariant 1 as applied to LHSes of rules
         all (ok_rule arity) (idCoreRules bndr)
+
         -- Invariant 2a: stable unfoldings
         -- See Note [Join points and INLINE pragmas]
       , ok_unfolding arity (realIdUnfolding bndr)
+
         -- Invariant 4: Satisfies polymorphism rule
       , isValidJoinPointType arity (idType bndr)
       = True
+
       | otherwise
       = False
 


From git at git.haskell.org  Tue Mar 27 08:29:39 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 27 Mar 2018 08:29:39 +0000 (UTC)
Subject: [commit: ghc] master: Comments only (f13a0fc)
Message-ID: <20180327082939.3126C3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/f13a0fc0bd33c513c0fadd1da58823d5fabfc5a7/ghc

>---------------------------------------------------------------

commit f13a0fc0bd33c513c0fadd1da58823d5fabfc5a7
Author: Simon Peyton Jones <simonpj at microsoft.com>
Date:   Mon Mar 26 11:26:42 2018 +0100

    Comments only


>---------------------------------------------------------------

f13a0fc0bd33c513c0fadd1da58823d5fabfc5a7
 compiler/deSugar/TmOracle.hs | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/compiler/deSugar/TmOracle.hs b/compiler/deSugar/TmOracle.hs
index 3644c78..d6364be 100644
--- a/compiler/deSugar/TmOracle.hs
+++ b/compiler/deSugar/TmOracle.hs
@@ -100,6 +100,10 @@ solveOneEq solver_env@(_,(_,env)) complex
   $ applySubstComplexEq env complex -- replace everything we already know
 
 -- | Solve a complex equality.
+-- Nothing => definitely unsatisfiable
+-- Just tms => I have added the complex equality and added
+--             it to the tmstate; the result may or may not be
+--             satisfiable
 solveComplexEq :: TmState -> ComplexEq -> Maybe TmState
 solveComplexEq solver_state@(standby, (unhandled, env)) eq@(e1, e2) = case eq of
   -- We cannot do a thing about these cases


From git at git.haskell.org  Tue Mar 27 12:54:47 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 27 Mar 2018 12:54:47 +0000 (UTC)
Subject: [commit: ghc] master: Fix the test for #13938 (3ebf05f)
Message-ID: <20180327125447.7E3D63A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/3ebf05f5410a3e89d4dc6d451aea5020706fa5b0/ghc

>---------------------------------------------------------------

commit 3ebf05f5410a3e89d4dc6d451aea5020706fa5b0
Author: Ryan Scott <ryan.gl.scott at gmail.com>
Date:   Tue Mar 27 08:52:15 2018 -0400

    Fix the test for #13938
    
    Only half of the test files were checked in for T13938.
    This commit adds the missing half.


>---------------------------------------------------------------

3ebf05f5410a3e89d4dc6d451aea5020706fa5b0
 testsuite/tests/dependent/should_compile/Makefile  |  5 ++
 testsuite/tests/dependent/should_compile/T13938.hs | 82 ++++------------------
 .../should_compile/{T13938.hs => T13938a.hs}       |  2 +-
 testsuite/tests/dependent/should_compile/all.T     |  3 +-
 4 files changed, 23 insertions(+), 69 deletions(-)

diff --git a/testsuite/tests/dependent/should_compile/Makefile b/testsuite/tests/dependent/should_compile/Makefile
index 9101fbd..0f85518 100644
--- a/testsuite/tests/dependent/should_compile/Makefile
+++ b/testsuite/tests/dependent/should_compile/Makefile
@@ -1,3 +1,8 @@
 TOP=../../..
 include $(TOP)/mk/boilerplate.mk
 include $(TOP)/mk/test.mk
+
+T13938:
+	$(RM) T13938a.hi T13938a.o T13938.hi T13938.o
+	'$(TEST_HC)' $(TEST_HC_OPTS) -O -c T13938a.hs
+	'$(TEST_HC)' $(TEST_HC_OPTS) -O -c T13938.hs
diff --git a/testsuite/tests/dependent/should_compile/T13938.hs b/testsuite/tests/dependent/should_compile/T13938.hs
index 3ba9e27..dd4f3d6 100644
--- a/testsuite/tests/dependent/should_compile/T13938.hs
+++ b/testsuite/tests/dependent/should_compile/T13938.hs
@@ -1,80 +1,28 @@
 {-# LANGUAGE AllowAmbiguousTypes #-}
-{-# LANGUAGE ConstraintKinds #-}
-{-# LANGUAGE ExistentialQuantification #-}
 {-# LANGUAGE GADTs #-}
 {-# LANGUAGE RankNTypes #-}
 {-# LANGUAGE ScopedTypeVariables #-}
-{-# LANGUAGE TemplateHaskell #-}
 {-# LANGUAGE TypeApplications #-}
 {-# LANGUAGE TypeFamilies #-}
 {-# LANGUAGE TypeInType #-}
 {-# LANGUAGE TypeOperators #-}
+{-# LANGUAGE UndecidableInstances #-}
 module T13938 where
 
-import Data.Kind (Type)
+import T13938a
+import Data.Kind
+import Data.Type.Equality
+import GHC.TypeLits
 
-data family Sing (a :: k)
-data instance Sing (z :: [a]) where
-  SNil  :: Sing '[]
-  SCons :: Sing x -> Sing xs -> Sing (x:xs)
+type family Length (l :: [a]) :: Nat where {}
+type family Map (f :: a ~> b) (l :: [a]) :: [b] where {}
 
-data TyFun :: Type -> Type -> Type
-type a ~> b = TyFun a b -> Type
-infixr 0 ~>
+type WhyMapPreservesLength (f :: x ~> y) (l :: [x])
+  = Length l :~: Length (Map f l)
+data WhyMapPreservesLengthSym1 (f :: x ~> y) :: [x] ~> Type
+type instance Apply (WhyMapPreservesLengthSym1 f) l = WhyMapPreservesLength f l
 
-type family Apply (f :: k1 ~> k2) (x :: k1) :: k2
-type a @@ b = Apply a b
-infixl 9 @@
-
-data FunArrow = (:->) -- ^ '(->)'
-              | (:~>) -- ^ '(~>)'
-
-class FunType (arr :: FunArrow) where
-  type Fun (k1 :: Type) arr (k2 :: Type) :: Type
-
-class FunType arr => AppType (arr :: FunArrow) where
-  type App k1 arr k2 (f :: Fun k1 arr k2) (x :: k1) :: k2
-
-type FunApp arr = (FunType arr, AppType arr)
-
-instance FunType (:->) where
-  type Fun k1 (:->) k2 = k1 -> k2
-
-$(return []) -- This is only necessary for GHC 8.0 -- GHC 8.2 is smarter
-
-instance AppType (:->) where
-  type App k1 (:->) k2 (f :: k1 -> k2) x = f x
-
-instance FunType (:~>) where
-  type Fun k1 (:~>) k2 = k1 ~> k2
-
-$(return [])
-
-instance AppType (:~>) where
-  type App k1 (:~>) k2 (f :: k1 ~> k2) x = f @@ x
-
-infixr 0 -?>
-type (-?>) (k1 :: Type) (k2 :: Type) (arr :: FunArrow) = Fun k1 arr k2
-
-elimList :: forall (a :: Type) (p :: [a] -> Type) (l :: [a]).
-            Sing l
-         -> p '[]
-         -> (forall (x :: a) (xs :: [a]). Sing x -> Sing xs -> p xs -> p (x:xs))
-         -> p l
-elimList = elimListPoly @(:->)
-
-elimListTyFun :: forall (a :: Type) (p :: [a] ~> Type) (l :: [a]).
-                 Sing l
-              -> p @@ '[]
-              -> (forall (x :: a) (xs :: [a]). Sing x -> Sing xs -> p @@ xs -> p @@ (x:xs))
-              -> p @@ l
-elimListTyFun = elimListPoly @(:~>) @_ @p
-
-elimListPoly :: forall (arr :: FunArrow) (a :: Type) (p :: ([a] -?> Type) arr) (l :: [a]).
-                FunApp arr
-             => Sing l
-             -> App [a] arr Type p '[]
-             -> (forall (x :: a) (xs :: [a]). Sing x -> Sing xs -> App [a] arr Type p xs -> App [a] arr Type p (x:xs))
-             -> App [a] arr Type p l
-elimListPoly SNil                      pNil _     = pNil
-elimListPoly (SCons x (xs :: Sing xs)) pNil pCons = pCons x xs (elimListPoly @arr @a @p @xs xs pNil pCons)
+mapPreservesLength :: forall (x :: Type) (y :: Type) (f :: x ~> y) (l :: [x]).
+                      Length l :~: Length (Map f l)
+mapPreservesLength
+  = elimListTyFun @x @(WhyMapPreservesLengthSym1 f) @l undefined undefined undefined
diff --git a/testsuite/tests/dependent/should_compile/T13938.hs b/testsuite/tests/dependent/should_compile/T13938a.hs
similarity index 99%
copy from testsuite/tests/dependent/should_compile/T13938.hs
copy to testsuite/tests/dependent/should_compile/T13938a.hs
index 3ba9e27..3a09292 100644
--- a/testsuite/tests/dependent/should_compile/T13938.hs
+++ b/testsuite/tests/dependent/should_compile/T13938a.hs
@@ -9,7 +9,7 @@
 {-# LANGUAGE TypeFamilies #-}
 {-# LANGUAGE TypeInType #-}
 {-# LANGUAGE TypeOperators #-}
-module T13938 where
+module T13938a where
 
 import Data.Kind (Type)
 
diff --git a/testsuite/tests/dependent/should_compile/all.T b/testsuite/tests/dependent/should_compile/all.T
index ab7ab3c..da25b22 100644
--- a/testsuite/tests/dependent/should_compile/all.T
+++ b/testsuite/tests/dependent/should_compile/all.T
@@ -28,6 +28,7 @@ test('T12176', normal, compile, [''])
 test('T14038', normal, compile, [''])
 test('T12742', normal, compile, [''])
 test('T13910', normal, compile, [''])
-test('T13938', normal, compile, [''])
+test('T13938', [extra_files(['T13938a.hs'])], run_command,
+     ['$MAKE -s --no-print-directory T13938'])
 test('T14556', normal, compile, [''])
 test('T14720', normal, compile, [''])


From git at git.haskell.org  Tue Mar 27 13:53:28 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 27 Mar 2018 13:53:28 +0000 (UTC)
Subject: [commit: ghc] master: configure: Throw error if OS is found to be
 msys (8cfd2e4)
Message-ID: <20180327135328.04C453A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/8cfd2e4e5832bd188816e64daaa95c9003437723/ghc

>---------------------------------------------------------------

commit 8cfd2e4e5832bd188816e64daaa95c9003437723
Author: Ben Gamari <bgamari.foss at gmail.com>
Date:   Mon Mar 26 15:18:00 2018 -0400

    configure: Throw error if OS is found to be msys
    
    Test Plan: Try running configure on Windows with msys and mingw
    toolchains
    
    Reviewers: Phyx, hvr
    
    Reviewed By: Phyx
    
    Subscribers: rwbarton, thomie, erikd, carter
    
    Differential Revision: https://phabricator.haskell.org/D4526


>---------------------------------------------------------------

8cfd2e4e5832bd188816e64daaa95c9003437723
 aclocal.m4 | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/aclocal.m4 b/aclocal.m4
index b0a3d44..5b0a679 100644
--- a/aclocal.m4
+++ b/aclocal.m4
@@ -1973,6 +1973,9 @@ AC_DEFUN([GHC_CONVERT_OS],[
       freebsd|netbsd|dragonfly|hpux|linuxaout|kfreebsdgnu|freebsd2|mingw32|darwin|nextstep2|nextstep3|sunos4|ultrix|haiku)
         $3="$1"
         ;;
+      msys)
+        AC_MSG_ERROR([Building GHC using the msys toolchain is not supported; please use mingw instead. Perhaps you need to set 'MSYSTEM=MINGW64 or MINGW32?'])
+        ;;
       aix*) # e.g. powerpc-ibm-aix7.1.3.0
         $3="aix"
         ;;


From git at git.haskell.org  Tue Mar 27 13:53:41 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 27 Mar 2018 13:53:41 +0000 (UTC)
Subject: [commit: ghc] master: CmmPipeline: add a second pass of
 CmmCommonBlockElim (d5c4d46)
Message-ID: <20180327135341.AB20C3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/d5c4d46a62ce6a0cfa6440344f707136eff18119/ghc

>---------------------------------------------------------------

commit d5c4d46a62ce6a0cfa6440344f707136eff18119
Author: Michal Terepeta <michal.terepeta at gmail.com>
Date:   Mon Mar 26 15:18:44 2018 -0400

    CmmPipeline: add a second pass of CmmCommonBlockElim
    
    The sinking pass often gets rid of unnecessary registers
    registers/assignements exposing more opportunities for CBE, so this
    commit adds a second round of CBE after the sinking pass and should
    fix #12915 (and some examples in #14226).
    
    Nofib results:
    * Binary size:         0.9% reduction on average
    * Compile allocations: 0.7% increase on average
    * Runtime:             noisy, two separate runs of nofib showed a tiny
                           reduction on average, (~0.2-0.3%), but I think
                           this is mostly noise
    * Compile time:        very noisy, but generally within +/- 0.5% (one
                           run faster, one slower)
    
    One interesting part of this change is that running CBE invalidates
    results of proc-point analysis. But instead of re-doing the whole
    analysis, we can use the map that CBE creates for replacing/comparing
    block labels (maps a redundant label to a useful one) to update the
    results of proc-point analysis. This lowers the overhead compared to the
    previous experiment in #12915.
    
    Signed-off-by: Michal Terepeta <michal.terepeta at gmail.com>
    
    Test Plan: ./validate
    
    Reviewers: bgamari, simonmar
    
    Reviewed By: simonmar
    
    Subscribers: rwbarton, thomie, carter
    
    GHC Trac Issues: #12915, #14226
    
    Differential Revision: https://phabricator.haskell.org/D4417


>---------------------------------------------------------------

d5c4d46a62ce6a0cfa6440344f707136eff18119
 compiler/cmm/CmmCommonBlockElim.hs |  8 ++++----
 compiler/cmm/CmmPipeline.hs        | 42 +++++++++++++++++++++++++++++++++++---
 2 files changed, 43 insertions(+), 7 deletions(-)

diff --git a/compiler/cmm/CmmCommonBlockElim.hs b/compiler/cmm/CmmCommonBlockElim.hs
index c91d553..ad10511 100644
--- a/compiler/cmm/CmmCommonBlockElim.hs
+++ b/compiler/cmm/CmmCommonBlockElim.hs
@@ -59,9 +59,10 @@ import Data.List (foldl')
 -- hashes, and at most once otherwise. Previously, we were slower, and people
 -- rightfully complained: #10397
 
--- TODO: Use optimization fuel
-elimCommonBlocks :: CmmGraph -> CmmGraph
-elimCommonBlocks g = replaceLabels env $ copyTicks env g
+type Subst = LabelMap BlockId
+
+elimCommonBlocks :: CmmGraph -> (CmmGraph, Subst)
+elimCommonBlocks g = (replaceLabels env $ copyTicks env g, env)
   where
      env = iterate mapEmpty blocks_with_key
      -- The order of blocks doesn't matter here, but revPostorder also drops any
@@ -73,7 +74,6 @@ elimCommonBlocks g = replaceLabels env $ copyTicks env g
 -- (so avoid comparing them again)
 type DistinctBlocks = [CmmBlock]
 type Key = [Label]
-type Subst = LabelMap BlockId
 
 -- The outer list groups by hash. We retain this grouping throughout.
 iterate :: Subst -> [[(Key, DistinctBlocks)]] -> Subst
diff --git a/compiler/cmm/CmmPipeline.hs b/compiler/cmm/CmmPipeline.hs
index 4d109a4..babdb0b 100644
--- a/compiler/cmm/CmmPipeline.hs
+++ b/compiler/cmm/CmmPipeline.hs
@@ -1,4 +1,5 @@
 {-# LANGUAGE BangPatterns #-}
+{-# LANGUAGE TypeFamilies #-}
 
 module CmmPipeline (
   -- | Converts C-- with an implicit stack and native C-- calls into
@@ -28,6 +29,8 @@ import Control.Monad
 import Outputable
 import Platform
 
+import Data.Maybe
+
 -----------------------------------------------------------------------------
 -- | Top level driver for C-- pipeline
 -----------------------------------------------------------------------------
@@ -67,9 +70,9 @@ cpsTop hsc_env proc =
                                           , do_layout = do_layout }} = h
 
        ----------- Eliminate common blocks -------------------------------------
-       g <- {-# SCC "elimCommonBlocks" #-}
-            condPass Opt_CmmElimCommonBlocks elimCommonBlocks g
-                          Opt_D_dump_cmm_cbe "Post common block elimination"
+       (g, _) <- {-# SCC "elimCommonBlocks" #-}
+                 condPass2 Opt_CmmElimCommonBlocks elimCommonBlocks g mapEmpty
+                           Opt_D_dump_cmm_cbe "Post common block elimination"
 
        -- Any work storing block Labels must be performed _after_
        -- elimCommonBlocks
@@ -104,6 +107,32 @@ cpsTop hsc_env proc =
             condPass Opt_CmmSink (cmmSink dflags) g
                      Opt_D_dump_cmm_sink "Sink assignments"
 
+       (g, call_pps, proc_points) <- do
+         -- Only do the second CBE if we did the sinking pass. Otherwise,
+         -- it's unlikely we'll have any new opportunities to find redundant
+         -- blocks.
+         if not (gopt Opt_CmmSink dflags)
+           then pure (g, call_pps, proc_points)
+           else do
+             (g, cbe_subst) <- {-# SCC "elimCommonBlocks2" #-}
+               condPass2
+                 Opt_CmmElimCommonBlocks elimCommonBlocks g mapEmpty
+                 Opt_D_dump_cmm_cbe "Post common block elimination 2"
+
+             -- CBE might invalidate the results of proc-point analysis (by
+             -- removing labels). So we need to fix it. Instead of re-doing
+             -- the whole analysis, we use the final substitution env from
+             -- CBE to update existing results.
+             let cbe_fix set bid =
+                   setInsert (fromMaybe bid (mapLookup bid cbe_subst)) set
+             let !new_call_pps = setFoldl cbe_fix setEmpty call_pps
+             let !new_proc_points
+                   | splitting_proc_points =
+                       setFoldl cbe_fix setEmpty proc_points
+                   | otherwise = new_call_pps
+
+             return (g, new_call_pps, new_proc_points)
+
        ------------- CAF analysis ----------------------------------------------
        let cafEnv = {-# SCC "cafAnal" #-} cafAnal g
        dumpWith dflags Opt_D_dump_cmm_caf "CAFEnv" (ppr cafEnv)
@@ -155,6 +184,13 @@ cpsTop hsc_env proc =
                     return g
                else return g
 
+        condPass2 flag pass g a dumpflag dumpname =
+            if gopt flag dflags
+               then do
+                    (g, a) <- return $ pass g
+                    dump dumpflag dumpname g
+                    return (g, a)
+               else return (g, a)
 
         -- we don't need to split proc points for the NCG, unless
         -- tablesNextToCode is off.  The latter is because we have no


From git at git.haskell.org  Tue Mar 27 13:53:55 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 27 Mar 2018 13:53:55 +0000 (UTC)
Subject: [commit: ghc] master: testsuite: Add test for #14965 (d1fb583)
Message-ID: <20180327135355.D0AFC3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/d1fb5831f574953661a3716720fbc798781d37eb/ghc

>---------------------------------------------------------------

commit d1fb5831f574953661a3716720fbc798781d37eb
Author: Ben Gamari <ben at smart-cactus.org>
Date:   Mon Mar 26 15:41:39 2018 -0400

    testsuite: Add test for #14965


>---------------------------------------------------------------

d1fb5831f574953661a3716720fbc798781d37eb
 testsuite/tests/simplCore/should_run/T14965.hs            | 15 +++++++++++++++
 .../tests/simplCore/should_run/T14965.stdout              |  0
 testsuite/tests/simplCore/should_run/T14965_Sep.hs        | 13 +++++++++++++
 testsuite/tests/simplCore/should_run/all.T                |  1 +
 4 files changed, 29 insertions(+)

diff --git a/testsuite/tests/simplCore/should_run/T14965.hs b/testsuite/tests/simplCore/should_run/T14965.hs
new file mode 100644
index 0000000..f4fa011
--- /dev/null
+++ b/testsuite/tests/simplCore/should_run/T14965.hs
@@ -0,0 +1,15 @@
+module Main (main) where
+
+import T14965_Sep
+
+main :: IO ()
+main = print $ cc bb
+
+bb :: Sep
+bb = catSep b1 b2
+
+b1 :: Sep
+b1 = Sep [] ["foo"] []
+
+b2 :: Sep
+b2 = Sep [] ["bar"] []
diff --git a/libraries/base/tests/IO/IOError002.stdout b/testsuite/tests/simplCore/should_run/T14965.stdout
similarity index 100%
copy from libraries/base/tests/IO/IOError002.stdout
copy to testsuite/tests/simplCore/should_run/T14965.stdout
diff --git a/testsuite/tests/simplCore/should_run/T14965_Sep.hs b/testsuite/tests/simplCore/should_run/T14965_Sep.hs
new file mode 100644
index 0000000..46c0f1b
--- /dev/null
+++ b/testsuite/tests/simplCore/should_run/T14965_Sep.hs
@@ -0,0 +1,13 @@
+module T14965_Sep where
+
+data Sep = Sep
+  { bugVanishesWithoutThis :: [()]
+  , middle :: [String]
+  , orThis :: [()]
+  }
+
+catSep :: Sep -> Sep -> Sep
+catSep (Sep a b c) (Sep x y z) = Sep (a ++ x) (b ++ y) (c ++ z)
+
+cc :: Sep -> Bool
+cc boost = elem "foo" $ middle boost
diff --git a/testsuite/tests/simplCore/should_run/all.T b/testsuite/tests/simplCore/should_run/all.T
index d697605..ca69565 100644
--- a/testsuite/tests/simplCore/should_run/all.T
+++ b/testsuite/tests/simplCore/should_run/all.T
@@ -83,3 +83,4 @@ test('T14868',
      [when((arch('powerpc64') or arch('powerpc64le')), expect_broken(11261))],
      compile_and_run, [''])
 test('T14894', normal, compile_and_run, [''])
+test('T14965', normal, compile_and_run, [''])


From git at git.haskell.org  Tue Mar 27 13:54:12 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 27 Mar 2018 13:54:12 +0000 (UTC)
Subject: [commit: ghc] master: rts: Fix profiled build after D4529 (ab9e986)
Message-ID: <20180327135412.860483A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/ab9e986e61c3fca3d6842a60a0b0c9625dac11b9/ghc

>---------------------------------------------------------------

commit ab9e986e61c3fca3d6842a60a0b0c9625dac11b9
Author: Ben Gamari <ben at smart-cactus.org>
Date:   Mon Mar 26 16:34:06 2018 -0400

    rts: Fix profiled build after D4529


>---------------------------------------------------------------

ab9e986e61c3fca3d6842a60a0b0c9625dac11b9
 rts/Stats.c | 8 ++++----
 rts/Stats.h | 2 ++
 2 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/rts/Stats.c b/rts/Stats.c
index 457f50d..3efa6cc 100644
--- a/rts/Stats.c
+++ b/rts/Stats.c
@@ -738,8 +738,8 @@ static void report_summary(const RTSSummaryStats* sum)
 
 #if defined(PROFILING)
     statsPrintf("  RP      time  %7.3fs  (%7.3fs elapsed)\n",
-                TimeToSecondsDbl(sum->rc_cpu_ns),
-                TimeToSecondsDbl(sum->rc_elapsed_ns));
+                TimeToSecondsDbl(sum->rp_cpu_ns),
+                TimeToSecondsDbl(sum->rp_elapsed_ns));
     statsPrintf("  PROF    time  %7.3fs  (%7.3fs elapsed)\n",
                 TimeToSecondsDbl(sum->hc_cpu_ns),
                 TimeToSecondsDbl(sum->hc_elapsed_ns));
@@ -901,8 +901,8 @@ static void report_machine_readable (const RTSSummaryStats * sum)
 #if defined(PROFILING)
     MR_STAT("rp_cpu_seconds", "f", TimeToSecondsDbl(sum->rp_cpu_ns));
     MR_STAT("rp_wall_seconds", "f", TimeToSecondsDbl(sum->rp_elapsed_ns));
-    MR_STAT("hc_cpu_seconds", "f", TimeToSecondsDbl(sum->hp_cpu_ns));
-    MR_STAT("hc_wall_seconds", "f", TimeToSecondsDbl(sum->hp_elapsed_ns));
+    MR_STAT("hc_cpu_seconds", "f", TimeToSecondsDbl(sum->hc_cpu_ns));
+    MR_STAT("hc_wall_seconds", "f", TimeToSecondsDbl(sum->hc_elapsed_ns));
 #endif
     MR_STAT("total_cpu_seconds", "f", TimeToSecondsDbl(stats.cpu_ns));
     MR_STAT("total_wall_seconds", "f",
diff --git a/rts/Stats.h b/rts/Stats.h
index 7cd49fc..fbcca11 100644
--- a/rts/Stats.h
+++ b/rts/Stats.h
@@ -9,6 +9,8 @@
 #pragma once
 
 #include "GetTime.h"
+#include "sm/GC.h"
+#include "Sparks.h"
 
 #include "BeginPrivate.h"
 


From git at git.haskell.org  Tue Mar 27 14:19:03 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 27 Mar 2018 14:19:03 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4395-new: Discard reflexive casts during
 Simplify (dd26724)
Message-ID: <20180327141903.5B9763A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/tdammers/D4395-new
Link       : http://ghc.haskell.org/trac/ghc/changeset/dd26724b23bfee3b9e18dc1dcaf519061ed6be65/ghc

>---------------------------------------------------------------

commit dd26724b23bfee3b9e18dc1dcaf519061ed6be65
Author: Richard Eisenberg <rae at cs.brynmawr.edu>
Date:   Fri Jan 26 22:42:46 2018 -0500

    Discard reflexive casts during Simplify
    
    Previously, we went to great lengths to build just the right
    reflexive casts, only to discard them shortly later. Now, just
    skip creating reflexive casts altogether.


>---------------------------------------------------------------

dd26724b23bfee3b9e18dc1dcaf519061ed6be65
 compiler/coreSyn/CoreOpt.hs    | 48 ++++++++++++++++++++++++------------------
 compiler/simplCore/Simplify.hs | 27 +++++++++++++++++++-----
 2 files changed, 50 insertions(+), 25 deletions(-)

diff --git a/compiler/coreSyn/CoreOpt.hs b/compiler/coreSyn/CoreOpt.hs
index 04e604e..e1eae8b 100644
--- a/compiler/coreSyn/CoreOpt.hs
+++ b/compiler/coreSyn/CoreOpt.hs
@@ -732,9 +732,11 @@ exprIsConApp_maybe (in_scope, id_unf) expr
     go subst (Tick t expr) cont
        | not (tickishIsCode t) = go subst expr cont
     go subst (Cast expr co1) (CC args co2)
-       | Just (args', co1') <- pushCoArgs (subst_co subst co1) args
+       | Just (args', m_co1') <- pushCoArgs (subst_co subst co1) args
             -- See Note [Push coercions in exprIsConApp_maybe]
-       = go subst expr (CC args' (co1' `mkTransCo` co2))
+       = case m_co1' of
+           Just co1' -> go subst expr (CC args' (co1' `mkTransCo` co2))
+           Nothing   -> go subst expr (CC args' co2)
     go subst (App fun arg) (CC args co)
        = go subst fun (CC (subst_arg subst arg : args) co)
     go subst (Lam var body) (CC (arg:args) co)
@@ -928,36 +930,40 @@ Here we implement the "push rules" from FC papers:
   by pushing the coercion into the arguments
 -}
 
-pushCoArgs :: Coercion -> [CoreArg] -> Maybe ([CoreArg], Coercion)
-pushCoArgs co []         = return ([], co)
-pushCoArgs co (arg:args) = do { (arg',  co1) <- pushCoArg  co  arg
-                              ; (args', co2) <- pushCoArgs co1 args
-                              ; return (arg':args', co2) }
+pushCoArgs :: Coercion -> [CoreArg] -> Maybe ([CoreArg], Maybe Coercion)
+pushCoArgs co []         = return ([], Just co)
+pushCoArgs co (arg:args) = do { (arg',  m_co1) <- pushCoArg  co  arg
+                              ; case m_co1 of
+                                  Just co1 -> do { (args', m_co2) <- pushCoArgs co1 args
+                                                 ; return (arg':args', m_co2) }
+                                  Nothing  -> return (arg':args, Nothing) }
 
-pushCoArg :: Coercion -> CoreArg -> Maybe (CoreArg, Coercion)
+pushCoArg :: Coercion -> CoreArg -> Maybe (CoreArg, Maybe Coercion)
 -- We have (fun |> co) arg, and we want to transform it to
 --         (fun arg) |> co
 -- This may fail, e.g. if (fun :: N) where N is a newtype
 -- C.f. simplCast in Simplify.hs
 -- 'co' is always Representational
+-- If the returned coercion is Nothing, then it would have been reflexive
+pushCoArg co (Type ty) = do { (ty', m_co') <- pushCoTyArg co ty
+                            ; return (Type ty', m_co') }
+pushCoArg co val_arg   = do { (arg_co, m_co') <- pushCoValArg co
+                            ; return (val_arg `mkCast` arg_co, m_co') }
 
-pushCoArg co (Type ty) = do { (ty', co') <- pushCoTyArg co ty
-                            ; return (Type ty', co') }
-pushCoArg co val_arg   = do { (arg_co, co') <- pushCoValArg co
-                            ; return (mkCast val_arg arg_co, co') }
-
-pushCoTyArg :: Coercion -> Type -> Maybe (Type, Coercion)
+pushCoTyArg :: CoercionR -> Type -> Maybe (Type, Maybe CoercionR)
 -- We have (fun |> co) @ty
 -- Push the coercion through to return
 --         (fun @ty') |> co'
 -- 'co' is always Representational
+-- If the returned coercion is Nothing, then it would have been reflexive;
+-- it's faster not to compute it, though.
 pushCoTyArg co ty
   | tyL `eqType` tyR
-  = Just (ty, mkRepReflCo (piResultTy tyR ty))
+  = Just (ty, Nothing)
 
   | isForAllTy tyL
   = ASSERT2( isForAllTy tyR, ppr co $$ ppr ty )
-    Just (ty `mkCastTy` mkSymCo co1, co2)
+    Just (ty `mkCastTy` mkSymCo co1, Just co2)
 
   | otherwise
   = Nothing
@@ -977,14 +983,16 @@ pushCoTyArg co ty
         -- co2 :: ty1[ (ty|>co1)/a1 ] ~ ty2[ ty/a2 ]
         -- Arg of mkInstCo is always nominal, hence mkNomReflCo
 
-pushCoValArg :: Coercion -> Maybe (Coercion, Coercion)
+pushCoValArg :: Coercion -> Maybe (Coercion, Maybe Coercion)
 -- We have (fun |> co) arg
 -- Push the coercion through to return
 --         (fun (arg |> co_arg)) |> co_res
 -- 'co' is always Representational
+-- If the second returned Coercion is actually Nothing, then no cast is necessary;
+-- the returned coercion would have been reflexive.
 pushCoValArg co
   | tyL `eqType` tyR
-  = Just (mkRepReflCo arg, mkRepReflCo res)
+  = Just (mkRepReflCo arg, Nothing)
 
   | isFunTy tyL
   , (co1, co2) <- decomposeFunCo co
@@ -992,12 +1000,12 @@ pushCoValArg co
               -- then co1 :: tyL1 ~ tyR1
               --      co2 :: tyL2 ~ tyR2
   = ASSERT2( isFunTy tyR, ppr co $$ ppr arg )
-    Just (mkSymCo co1, co2)
+    Just (mkSymCo co1, Just co2)
 
   | otherwise
   = Nothing
   where
-    (arg, res)   = splitFunTy tyR
+    (arg, _)     = splitFunTy tyR
     Pair tyL tyR = coercionKind co
 
 pushCoercionIntoLambda
diff --git a/compiler/simplCore/Simplify.hs b/compiler/simplCore/Simplify.hs
index 53e3a21..bb7cd2c 100644
--- a/compiler/simplCore/Simplify.hs
+++ b/compiler/simplCore/Simplify.hs
@@ -1207,23 +1207,40 @@ simplCast env body co0 cont0
         ; cont1 <- addCoerce co1 cont0
         ; simplExprF env body cont1 }
   where
+        -- If the first parameter is Nothing, then simplifying revealed a
+        -- reflexive coercion. Omit.
+       addCoerce0 :: Maybe OutCoercion -> SimplCont -> SimplM SimplCont
+       addCoerce0 Nothing   cont = return cont
+       addCoerce0 (Just co) cont = addCoerce co cont
+
        addCoerce :: OutCoercion -> SimplCont -> SimplM SimplCont
+       addCoerce co cont  -- just skip reflexive casts
+         | isReflexiveCo co = {-#SCC "addCoerce-reflexive" #-}
+                              return cont
+                -- It's worth checking isReflexiveCo.
+                -- For example, in the initial form of a worker
+                -- we may find  (coerce T (coerce S (\x.e))) y
+                -- and we'd like it to simplify to e[y/x] in one round
+                -- of simplification
+
        addCoerce co1 (CastIt co2 cont)
          = addCoerce (mkTransCo co1 co2) cont
 
        addCoerce co cont@(ApplyToTy { sc_arg_ty = arg_ty, sc_cont = tail })
-         | Just (arg_ty', co') <- pushCoTyArg co arg_ty
-         = do { tail' <- addCoerce co' tail
-              ; return (cont { sc_arg_ty = arg_ty', sc_cont = tail' }) }
+         | Just (arg_ty', m_co') <- pushCoTyArg co arg_ty
+         = case m_co' of
+             Just co' -> do { tail' <- addCoerce co' tail
+                            ; return (cont { sc_arg_ty = arg_ty', sc_cont = tail' }) }
+             Nothing  -> return cont
 
        addCoerce co cont@(ApplyToVal { sc_arg = arg, sc_env = arg_se
                                 , sc_dup = dup, sc_cont = tail })
-         | Just (co1, co2) <- pushCoValArg co
+         | Just (co1, m_co2) <- pushCoValArg co
          , Pair _ new_ty <- coercionKind co1
          , not (isTypeLevPoly new_ty)  -- without this check, we get a lev-poly arg
                                        -- See Note [Levity polymorphism invariants] in CoreSyn
                                        -- test: typecheck/should_run/EtaExpandLevPoly
-         = do { tail' <- addCoerce co2 tail
+         = do { tail' <- addCoerce0 m_co2 tail
               ; if isReflCo co1
                 then return (cont { sc_cont = tail' })
                      -- Avoid simplifying if possible;


From git at git.haskell.org  Tue Mar 27 14:19:06 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 27 Mar 2018 14:19:06 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4395-new: Fix huge performance regression
 (b89c615)
Message-ID: <20180327141906.2EA5B3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/tdammers/D4395-new
Link       : http://ghc.haskell.org/trac/ghc/changeset/b89c615edfea6a05623946064fef2933dbfe1ae5/ghc

>---------------------------------------------------------------

commit b89c615edfea6a05623946064fef2933dbfe1ae5
Author: Tobias Dammers <tdammers at gmail.com>
Date:   Mon Mar 26 13:44:56 2018 +0200

    Fix huge performance regression
    
    Previous version caused a 10x increase in execution time for the
    infamous Grammar.hs test case from #14683; this patch gets us back on
    par.


>---------------------------------------------------------------

b89c615edfea6a05623946064fef2933dbfe1ae5
 compiler/simplCore/Simplify.hs | 102 +++++++++++++++++++----------------------
 1 file changed, 46 insertions(+), 56 deletions(-)

diff --git a/compiler/simplCore/Simplify.hs b/compiler/simplCore/Simplify.hs
index bb7cd2c..eb5b672 100644
--- a/compiler/simplCore/Simplify.hs
+++ b/compiler/simplCore/Simplify.hs
@@ -1209,62 +1209,52 @@ simplCast env body co0 cont0
   where
         -- If the first parameter is Nothing, then simplifying revealed a
         -- reflexive coercion. Omit.
-       addCoerce0 :: Maybe OutCoercion -> SimplCont -> SimplM SimplCont
-       addCoerce0 Nothing   cont = return cont
-       addCoerce0 (Just co) cont = addCoerce co cont
-
-       addCoerce :: OutCoercion -> SimplCont -> SimplM SimplCont
-       addCoerce co cont  -- just skip reflexive casts
-         | isReflexiveCo co = {-#SCC "addCoerce-reflexive" #-}
-                              return cont
-                -- It's worth checking isReflexiveCo.
-                -- For example, in the initial form of a worker
-                -- we may find  (coerce T (coerce S (\x.e))) y
-                -- and we'd like it to simplify to e[y/x] in one round
-                -- of simplification
-
-       addCoerce co1 (CastIt co2 cont)
-         = addCoerce (mkTransCo co1 co2) cont
-
-       addCoerce co cont@(ApplyToTy { sc_arg_ty = arg_ty, sc_cont = tail })
-         | Just (arg_ty', m_co') <- pushCoTyArg co arg_ty
-         = case m_co' of
-             Just co' -> do { tail' <- addCoerce co' tail
-                            ; return (cont { sc_arg_ty = arg_ty', sc_cont = tail' }) }
-             Nothing  -> return cont
-
-       addCoerce co cont@(ApplyToVal { sc_arg = arg, sc_env = arg_se
-                                , sc_dup = dup, sc_cont = tail })
-         | Just (co1, m_co2) <- pushCoValArg co
-         , Pair _ new_ty <- coercionKind co1
-         , not (isTypeLevPoly new_ty)  -- without this check, we get a lev-poly arg
-                                       -- See Note [Levity polymorphism invariants] in CoreSyn
-                                       -- test: typecheck/should_run/EtaExpandLevPoly
-         = do { tail' <- addCoerce0 m_co2 tail
-              ; if isReflCo co1
-                then return (cont { sc_cont = tail' })
-                     -- Avoid simplifying if possible;
-                     -- See Note [Avoiding exponential behaviour]
-                else do
-              { (dup', arg_se', arg') <- simplArg env dup arg_se arg
-                   -- When we build the ApplyTo we can't mix the OutCoercion
-                   -- 'co' with the InExpr 'arg', so we simplify
-                   -- to make it all consistent.  It's a bit messy.
-                   -- But it isn't a common case.
-                   -- Example of use: Trac #995
-              ; return (ApplyToVal { sc_arg  = mkCast arg' co1
-                                   , sc_env  = arg_se'
-                                   , sc_dup  = dup'
-                                   , sc_cont = tail' }) } }
-
-       addCoerce co cont
-         | isReflexiveCo co = return cont
-         | otherwise        = return (CastIt co cont)
-                -- It's worth checking isReflexiveCo.
-                -- For example, in the initial form of a worker
-                -- we may find  (coerce T (coerce S (\x.e))) y
-                -- and we'd like it to simplify to e[y/x] in one round
-                -- of simplification
+        addCoerce0 :: Maybe OutCoercion -> SimplCont -> SimplM SimplCont
+        addCoerce0 Nothing   cont = return cont
+        addCoerce0 (Just co) cont = addCoerce co cont
+
+        addCoerce :: OutCoercion -> SimplCont -> SimplM SimplCont
+
+        addCoerce co1 (CastIt co2 cont)
+          = addCoerce (mkTransCo co1 co2) cont
+
+        addCoerce co cont@(ApplyToTy { sc_arg_ty = arg_ty, sc_cont = tail })
+          | Just (arg_ty', m_co') <- pushCoTyArg co arg_ty
+          = do { tail' <- addCoerce0 m_co' tail
+               ; return (cont { sc_arg_ty = arg_ty', sc_cont = tail' }) }
+
+        addCoerce co cont@(ApplyToVal { sc_arg = arg, sc_env = arg_se
+                                 , sc_dup = dup, sc_cont = tail })
+          | Just (co1, m_co2) <- pushCoValArg co
+          , Pair _ new_ty <- coercionKind co1
+          , not (isTypeLevPoly new_ty)  -- without this check, we get a lev-poly arg
+                                        -- See Note [Levity polymorphism invariants] in CoreSyn
+                                        -- test: typecheck/should_run/EtaExpandLevPoly
+          = do { tail' <- addCoerce0 m_co2 tail
+               ; if isReflCo co1
+                 then return (cont { sc_cont = tail' })
+                      -- Avoid simplifying if possible;
+                      -- See Note [Avoiding exponential behaviour]
+                 else do
+               { (dup', arg_se', arg') <- simplArg env dup arg_se arg
+                    -- When we build the ApplyTo we can't mix the OutCoercion
+                    -- 'co' with the InExpr 'arg', so we simplify
+                    -- to make it all consistent.  It's a bit messy.
+                    -- But it isn't a common case.
+                    -- Example of use: Trac #995
+               ; return (ApplyToVal { sc_arg  = mkCast arg' co1
+                                    , sc_env  = arg_se'
+                                    , sc_dup  = dup'
+                                    , sc_cont = tail' }) } }
+
+        addCoerce co cont
+          | isReflexiveCo co = return cont
+          | otherwise        = return (CastIt co cont)
+                 -- It's worth checking isReflexiveCo.
+                 -- For example, in the initial form of a worker
+                 -- we may find  (coerce T (coerce S (\x.e))) y
+                 -- and we'd like it to simplify to e[y/x] in one round
+                 -- of simplification
 
 simplArg :: SimplEnv -> DupFlag -> StaticEnv -> CoreExpr
          -> SimplM (DupFlag, StaticEnv, OutExpr)


From git at git.haskell.org  Tue Mar 27 14:19:08 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 27 Mar 2018 14:19:08 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4395-new's head updated: Fix huge
 performance regression (b89c615)
Message-ID: <20180327141908.D4F113A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

Branch 'wip/tdammers/D4395-new' now includes:

     2756117 Revert "Better stats for T5837"
     b8f03bb Cache the fingerprint of sOpt_P
     e261b85 forkProcess: fix task mutex release order
     8dab89b rts: Note functions which must take all_tasks_mutex.
     f8e3cd3 Only load plugins once
     d8e47a2 Make cost centre symbol names deterministic.
     8c7a155 Move Data.Functor.Contravariant from the contravariant package to base.
     e8e9f6a Improve exhaustive checking for guards in pattern bindings and MultiIf.
     125d151 Add regression test for #12790
     aef2b42 Fix #14817 by not double-printing data family instance kind signatures
     4a0d0d8 Various Windows / Cross Compile to Windows fixes
     1773964 DynFlags: Support British spelling of GeneralisedNewtypeDeriving
     969e747 GHCi info: Use src file for cache invalidation
     6a7e159 Improve missing-home-modules warning formatting
     5c28ee8 Add @since annotations for derived instances in base
     6e4fa81 rts/win32: Assert that the IO manager has been initialised
     bc1bcaa configure: Enable LD_NO_GOLD is set in all codepaths
     7782b47 Add Applicative, Semigroup, and Monoid instances in GHC.Generics
     e4dcebf Adds *-cross-ncg flavour.
     6835702 Permit conversion of partially applied PromotedTupleTs
     ffb2738 Fix #14838 by marking TH-spliced code as FromSource
     5f6fcf7 Compile with `--via-asm` when cross compiling.
     44ba60f doCorePass: Expand catch-all
     821daad Correct default -A value in RTS flag usage info
     a2d03c6 Fix the coverage checker's treatment of existential tyvars
     99c556d Parenthesize (() :: Constraint) in argument position
     4631ceb Bump hsc2hs submodule
     8f0b2f5 Bump Cabal submodule to 2.2
     a9f680f Bump Cabal submodule
     e7653bc Wombling around in Trac #14808
     3d25203 Respect Note [The tcType invariant]
     6ee831f Fix #14888 by adding more special cases for ArrowT
     1c062b7 Simplify rnLHsInstType
     df7ac37 Fixup include of gmp/config.mk to use new location
     f6cf400 `--via-asm` only for windows targets
     cf5bc96 add CCX=$(CXX) to integer-gmp
     ee597e9 Schedule.c: remove a redundant CPP guard
     5bc195a Allow top level ticked string literals
     9bccfcd Correct -g flag description
     64c0af7 cmm/: Avoid using lazy left folds
     08345bd Make accumArray and accum stricter
     1488591 Bump nofib submodule
     488d63d Fix interpreter with profiling
     40c4313 Add perf test for #14052
     b120e64 Add bindist-list.uniq to .gitignore
     d9d4632 Schedule.c: remove unreachable code block
     648cb28 Use docker images with non-root user
     b320ba8 Fix a typo about pattern synonyms in documentation.
     b3bfbed Users Guide: Add that --numa is available on Windows too
     43fbb90 Fix typo in description of -V RTS flag
     d99a65a Add -fexternal-dynamic-refs
     98c7749 Revert "GHCi: Don't remove shadowed bindings from typechecker scope."
     bc95fed Error message and doc improvements for #14335
     ed6f9fb ghc-prim: Reduce scope of Clang sync_fetch_and_nand workaround
     94f0254 ghc-prim: Silence -Wsync-nand warning in atomic.c
     47e2a28 Remove outdated documentation bits concerning -Wmissing-methods
     a25b763 configure: Accept suffix in OpenBSD triple's OS name
     df2ea10 Compacted arrays are pinned for isByteArrayPinned#
     dd3906b UNREG: fix implicit declarations from pdep and pext
     8e34101 Fix a debug print in disassembler (#14905)
     e3ae0eb testsuite: disable T13615 on non-smp targets
     5c804e5 Remove splitEithers, use partitionEithers from base
     02b3dad Bump Cabal submodule
     50972d6 Comment improvements on interpreter breakpoint IO action
     ba57979 Update a comment in Exception.cmm
     152055a Drop GHC 8.0 compatibility
     cb6d858 Slighly improve infix con app pattern errors
     1522cf0 aclocal.m4: allow more GNU/Hurd tuples
     0693b0b aclocal.m4: add OSHurd (debian patch)
     2a3702d Comments and tiny refactor
     5a1ad23 Update test for #5129:
     f9a6d42 Add a build with 32bit Ubuntu container
     2918abf rts: Add --internal-counters RTS flag and several counters
     3d378d9 Also check local rules with -frules-check
     39c7406 Be more selective in which conditionals we invert
     fad822e Improve the warning message of qualified unused imports.
     0db0e46 Get rid of more CPP in cmm/ and codeGen/
     bbcea13 Hoopl: improve postorder calculation
     a00b88b Implement -dword-hex-literals
     b37a87b PPC nativeGen: Add support for MO_SS_Conv_W32_W64
     5241f29 SPARC nativeGen: Support for MO_SS_Conv_W32_W64
     d27336e [RFC] nativeGen: Add support for MO_SS_Conv_W32_W64 on i386
     20cbb01 Improve accuracy of get/setAllocationCounter
     256577f CmmUtils: get rid of insertBlock
     fbd9b88 Implement equalKeysUFM the right way
     9868f91 Turn a TH Name for built-in syntax into an unqualified RdrName
     e358854 Require GHC 8.2 to bootstrap GHC
     c3aea39 Fix #14934 by including axSub0R in typeNatCoAxiomRules
     f748c52 Don't permit data types with return kind Constraint
     fdec06a Update tests for #12870 to pass with a slow run of the testsuite.
     98c1f22 Bump array submodule
     960cd42 Fix typo in user guide about ConstraintKinds
     82e8d1f Fix typo
     b3b394b gen-data-layout.sh: Use bash array for readability
     2d4bda2 rts, base: Refactor stats.c to improve --machine-readable report
     afad556 Add -flate-specialise which runs a later specialisation pass
     6a71ef7 Bump autoconf version bound to >= 2.69
     d718023 relnotes: Fix parsing of Version: field from Cabal file
     60aa53d configure: Accept version suffix in solaris name
     57001d9 Update T5129 test:
     0a778eb Revert "rts, base: Refactor stats.c to improve --machine-readable report"
     abaf43d Fix seq# case of exprOkForSpeculation
     49ac3f0 Fix #14869 by being more mindful of Type vs. Constraint
     411a97e Allow as-patterns in unidirectional patttern synonyms
     3446cee Fix two obscure bugs in rule matching
     efc844f Fix over-eager constant folding in bitInteger
     034c32f Improve shortOutIndirections slightly
     d5577f4 Special-case record fields ending with hash when deriving Read
     affdea8 Allow PartialTypeSignatures in standalone deriving contexts
     ceb9147 Support adding objects from TH
     7bb1fde testsuite: Add test for #14931
     10566a8 Support iOS variants elsewhere when configuring
     9893042 Fix two pernicious bugs in DeriveAnyClass
     cf80995 Add Note [BLACKHOLE points to IND]
     f7bbc34 Run C finalizers incrementally during mutation
     fb462f9 Fix panic on module re-exports of DuplicateRcordFields
     c16df60 document: fix trac issue #14229
     9a00bfb rts/RetainerProfile: Dump closure type if push() fails
     0703c00 testsuite: Add test for #14925
     20f14b4 Fix #14916 with an additional validity check in deriveTyData
     0cbb13b Don't refer to blocks in debug info when -g1
     a3986d7 Fix scoped type variables in TH for several constructs
     41db237 llvmGen: Pass -optlo flags last to opt
     20ae19f base: Fix Unicode handling of TyCon's Show instance
     ecfb4d3 Add new debugging flag -dinline-check
     efd70cf Add unaligned bytearray access primops. Fixes #4442.
     d152dab Add a job running on Fedora
     60e29dc circleci: Bump Hackage index state
     dd26724 Discard reflexive casts during Simplify
     b89c615 Fix huge performance regression

From git at git.haskell.org  Tue Mar 27 14:28:20 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 27 Mar 2018 14:28:20 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4394: Applying patch suggested in #11735
 to improve coercionKind perf (4e9fa93)
Message-ID: <20180327142820.426563A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/tdammers/D4394
Link       : http://ghc.haskell.org/trac/ghc/changeset/4e9fa93abaa4379e62da3248842b687b42a73708/ghc

>---------------------------------------------------------------

commit 4e9fa93abaa4379e62da3248842b687b42a73708
Author: Tobias Dammers <tdammers at gmail.com>
Date:   Wed Jan 24 16:05:55 2018 +0100

    Applying patch suggested in #11735 to improve coercionKind perf


>---------------------------------------------------------------

4e9fa93abaa4379e62da3248842b687b42a73708
 compiler/types/Coercion.hs | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/compiler/types/Coercion.hs b/compiler/types/Coercion.hs
index c8105d0..66cb498 100644
--- a/compiler/types/Coercion.hs
+++ b/compiler/types/Coercion.hs
@@ -1755,6 +1755,8 @@ substitute for them all at once.  Remarkably, for Trac #11735 this single
 change reduces /total/ compile time by a factor of more than ten.
 
 -}
+=======
+>>>>>>> Applying patch suggested in #11735 to improve coercionKind perf
 
 -- | Apply 'coercionKind' to multiple 'Coercion's
 coercionKinds :: [Coercion] -> Pair [Type]


From git at git.haskell.org  Tue Mar 27 14:28:23 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 27 Mar 2018 14:28:23 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4394: Caching coercion roles in NthCo
 (#11735) (85e4b46)
Message-ID: <20180327142823.248CC3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/tdammers/D4394
Link       : http://ghc.haskell.org/trac/ghc/changeset/85e4b462d22e49363f1ac7683dd13f80e55b6d8d/ghc

>---------------------------------------------------------------

commit 85e4b462d22e49363f1ac7683dd13f80e55b6d8d
Author: Tobias Dammers <tdammers at gmail.com>
Date:   Thu Jan 25 20:33:58 2018 +0100

    Caching coercion roles in NthCo (#11735)


>---------------------------------------------------------------

85e4b462d22e49363f1ac7683dd13f80e55b6d8d
 compiler/coreSyn/CoreFVs.hs      |  2 +-
 compiler/coreSyn/CoreLint.hs     |  2 +-
 compiler/iface/TcIface.hs        |  2 +-
 compiler/iface/ToIface.hs        |  2 +-
 compiler/typecheck/TcTyDecls.hs  |  2 +-
 compiler/typecheck/TcType.hs     |  2 +-
 compiler/typecheck/TcUnify.hs    |  2 +-
 compiler/typecheck/TcValidity.hs |  2 +-
 compiler/types/Coercion.hs       | 45 ++++++++++++++++++++++------------------
 compiler/types/FamInstEnv.hs     |  2 +-
 compiler/types/OptCoercion.hs    |  4 ++--
 compiler/types/TyCoRep.hs        | 36 +++++++++++++++++++++++++-------
 compiler/types/Type.hs           |  8 +++----
 13 files changed, 68 insertions(+), 43 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc 85e4b462d22e49363f1ac7683dd13f80e55b6d8d

From git at git.haskell.org  Tue Mar 27 14:28:25 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 27 Mar 2018 14:28:25 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4394: Refactored coercionKindsRole (as
 per #11735) (fcc65df)
Message-ID: <20180327142825.E0E483A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/tdammers/D4394
Link       : http://ghc.haskell.org/trac/ghc/changeset/fcc65dfac36c038c4685e06c7988dc99467e5fd7/ghc

>---------------------------------------------------------------

commit fcc65dfac36c038c4685e06c7988dc99467e5fd7
Author: Tobias Dammers <tdammers at gmail.com>
Date:   Wed Jan 24 17:20:20 2018 +0100

    Refactored coercionKindsRole (as per #11735)


>---------------------------------------------------------------

fcc65dfac36c038c4685e06c7988dc99467e5fd7
 compiler/types/Coercion.hs | 74 ++++++++++++++++------------------------------
 1 file changed, 25 insertions(+), 49 deletions(-)

diff --git a/compiler/types/Coercion.hs b/compiler/types/Coercion.hs
index 66cb498..9c78b4b 100644
--- a/compiler/types/Coercion.hs
+++ b/compiler/types/Coercion.hs
@@ -1765,77 +1765,53 @@ coercionKinds tys = sequenceA $ map coercionKind tys
 -- | Get a coercion's kind and role.
 -- Why both at once?  See Note [Computing a coercion kind and role]
 coercionKindRole :: Coercion -> (Pair Type, Role)
-coercionKindRole = go
+coercionKindRole co = (coercionKind co, coercionRole co)
+
+-- | Retrieve the role from a coercion.
+coercionRole :: Coercion -> Role
+coercionRole = go
   where
-    go (Refl r ty) = (Pair ty ty, r)
-    go (TyConAppCo r tc cos)
-      = (mkTyConApp tc <$> (sequenceA $ map coercionKind cos), r)
-    go (AppCo co1 co2)
-      = let (tys1, r1) = go co1 in
-        (mkAppTy <$> tys1 <*> coercionKind co2, r1)
-    go (ForAllCo tv1 k_co co)
-      = let Pair _ k2          = coercionKind k_co
-            tv2                = setTyVarKind tv1 k2
-            (Pair ty1 ty2, r)  = go co
-            subst = zipTvSubst [tv1] [TyVarTy tv2 `mkCastTy` mkSymCo k_co]
-            ty2' = substTyAddInScope subst ty2 in
-            -- We need free vars of ty2 in scope to satisfy the invariant
-            -- from Note [The substitution invariant]
-            -- This is doing repeated substitutions and probably doesn't
-            -- need to, see #11735
-        (mkInvForAllTy <$> Pair tv1 tv2 <*> Pair ty1 ty2', r)
-    go (FunCo r co1 co2)
-      = (mkFunTy <$> coercionKind co1 <*> coercionKind co2, r)
+    go (Refl r _) = r
+    go (TyConAppCo r _ _) = r
+    go (AppCo co1 _) = go co1
+    go (ForAllCo _ _ co) = go co
+    go (FunCo r _ _) = r
     go (CoVarCo cv) = go_var cv
     go (HoleCo h)   = go_var (coHoleCoVar h)
-    go co@(AxiomInstCo ax _ _) = (coercionKind co, coAxiomRole ax)
-    go (UnivCo _ r ty1 ty2)  = (Pair ty1 ty2, r)
-    go (SymCo co) = first swap $ go co
-    go (TransCo co1 co2)
-      = let (tys1, r) = go co1 in
-        (Pair (pFst tys1) (pSnd $ coercionKind co2), r)
+    go (AxiomInstCo ax _ _) = coAxiomRole ax
+    go (UnivCo _ r _ _)  = r
+    go (SymCo co) = go co
+    go (TransCo co1 co2) = go co1
     go (NthCo d co)
       | Just (tv1, _) <- splitForAllTy_maybe ty1
       = ASSERT( d == 0 )
-        let (tv2, _) = splitForAllTy ty2 in
-        (tyVarKind <$> Pair tv1 tv2, Nominal)
+        Nominal
 
       | otherwise
       = let (tc1,  args1) = splitTyConApp ty1
             (_tc2, args2) = splitTyConApp ty2
         in
         ASSERT2( tc1 == _tc2, ppr d $$ ppr tc1 $$ ppr _tc2 )
-        ((`getNth` d) <$> Pair args1 args2, nthRole r tc1 d)
+        (nthRole r tc1 d)
 
       where
-        (Pair ty1 ty2, r) = go co
-    go co@(LRCo {}) = (coercionKind co, Nominal)
+        (Pair ty1 ty2, r) = coercionKindRole co
+    go (LRCo {}) = Nominal
     go (InstCo co arg) = go_app co [arg]
-    go (CoherenceCo co1 co2)
-      = let (Pair t1 t2, r) = go co1 in
-        (Pair (t1 `mkCastTy` co2) t2, r)
-    go co@(KindCo {}) = (coercionKind co, Nominal)
-    go (SubCo co) = (coercionKind co, Representational)
-    go co@(AxiomRuleCo ax _) = (coercionKind co, coaxrRole ax)
+    go (CoherenceCo co1 _) = go co1
+    go (KindCo {}) = Nominal
+    go (SubCo _) = Representational
+    go (AxiomRuleCo ax _) = coaxrRole ax
 
     -------------
-    go_var cv = (coVarTypes cv, coVarRole cv)
+    go_var = coVarRole
 
     -------------
-    go_app :: Coercion -> [Coercion] -> (Pair Type, Role)
+    go_app :: Coercion -> [Coercion] -> Role
     -- Collect up all the arguments and apply all at once
     -- See Note [Nested InstCos]
     go_app (InstCo co arg) args = go_app co (arg:args)
-    go_app co              args
-      = let (pair, r) = go co in
-        (piResultTys <$> pair <*> (sequenceA $ map coercionKind args), r)
-
--- | Retrieve the role from a coercion.
-coercionRole :: Coercion -> Role
-coercionRole = snd . coercionKindRole
-  -- There's not a better way to do this, because NthCo needs the *kind*
-  -- and role of its argument. Luckily, laziness should generally avoid
-  -- the need for computing kinds in other cases.
+    go_app co              args = go co
 
 {-
 Note [Nested InstCos]


From git at git.haskell.org  Tue Mar 27 14:28:28 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 27 Mar 2018 14:28:28 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4394: Simplification as per #11735
 (2adc093)
Message-ID: <20180327142828.A9EF33A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/tdammers/D4394
Link       : http://ghc.haskell.org/trac/ghc/changeset/2adc093c63b0d44d3e669b6fed844c6e7e5d107d/ghc

>---------------------------------------------------------------

commit 2adc093c63b0d44d3e669b6fed844c6e7e5d107d
Author: Tobias Dammers <tdammers at gmail.com>
Date:   Thu Jan 25 11:16:30 2018 +0100

    Simplification as per #11735
    
    (https://ghc.haskell.org/trac/ghc/ticket/11735#comment:19)


>---------------------------------------------------------------

2adc093c63b0d44d3e669b6fed844c6e7e5d107d
 compiler/types/Coercion.hs | 10 ++++------
 1 file changed, 4 insertions(+), 6 deletions(-)

diff --git a/compiler/types/Coercion.hs b/compiler/types/Coercion.hs
index 9c78b4b..4cc8cef 100644
--- a/compiler/types/Coercion.hs
+++ b/compiler/types/Coercion.hs
@@ -1797,7 +1797,7 @@ coercionRole = go
       where
         (Pair ty1 ty2, r) = coercionKindRole co
     go (LRCo {}) = Nominal
-    go (InstCo co arg) = go_app co [arg]
+    go (InstCo co arg) = go_app co
     go (CoherenceCo co1 _) = go co1
     go (KindCo {}) = Nominal
     go (SubCo _) = Representational
@@ -1807,11 +1807,9 @@ coercionRole = go
     go_var = coVarRole
 
     -------------
-    go_app :: Coercion -> [Coercion] -> Role
-    -- Collect up all the arguments and apply all at once
-    -- See Note [Nested InstCos]
-    go_app (InstCo co arg) args = go_app co (arg:args)
-    go_app co              args = go co
+    go_app :: Coercion -> Role
+    go_app (InstCo co arg) = go_app co
+    go_app co              = go co
 
 {-
 Note [Nested InstCos]


From git at git.haskell.org  Tue Mar 27 14:28:31 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 27 Mar 2018 14:28:31 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4394: Added SCCs to hunt down #14683
 (0019570)
Message-ID: <20180327142831.83C3F3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/tdammers/D4394
Link       : http://ghc.haskell.org/trac/ghc/changeset/0019570f9ccd9b5bd50ba8f0ea9ee0021c55e2fb/ghc

>---------------------------------------------------------------

commit 0019570f9ccd9b5bd50ba8f0ea9ee0021c55e2fb
Author: Tobias Dammers <tdammers at gmail.com>
Date:   Wed Jan 24 16:07:00 2018 +0100

    Added SCCs to hunt down #14683


>---------------------------------------------------------------

0019570f9ccd9b5bd50ba8f0ea9ee0021c55e2fb
 compiler/simplCore/Simplify.hs | 72 +++++++++++++++++++++++++-----------------
 compiler/types/TyCoRep.hs      |  9 +++---
 2 files changed, 48 insertions(+), 33 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc 0019570f9ccd9b5bd50ba8f0ea9ee0021c55e2fb

From git at git.haskell.org  Tue Mar 27 14:28:34 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 27 Mar 2018 14:28:34 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4394: Fixed NthCo Note (discussion in
 D4385) (7ef2f9c)
Message-ID: <20180327142834.53CE43A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/tdammers/D4394
Link       : http://ghc.haskell.org/trac/ghc/changeset/7ef2f9ccab2fa39537a9af4a6a2a313d84a9b031/ghc

>---------------------------------------------------------------

commit 7ef2f9ccab2fa39537a9af4a6a2a313d84a9b031
Author: Tobias Dammers <tdammers at gmail.com>
Date:   Wed Feb 7 13:19:33 2018 +0100

    Fixed NthCo Note (discussion in D4385)
    
    https://phabricator.haskell.org/D4385#inline-34161


>---------------------------------------------------------------

7ef2f9ccab2fa39537a9af4a6a2a313d84a9b031
 compiler/types/TyCoRep.hs | 22 ++++++++++++++--------
 1 file changed, 14 insertions(+), 8 deletions(-)

diff --git a/compiler/types/TyCoRep.hs b/compiler/types/TyCoRep.hs
index 93ec274..cd295f7 100644
--- a/compiler/types/TyCoRep.hs
+++ b/compiler/types/TyCoRep.hs
@@ -1236,14 +1236,20 @@ in the "Safe Coercions" paper (ICFP '14).
 
 Note [NthCo Cached Roles]
 ~~~~~~~~~~~~~~~~~~~~~~~~~
-Looking at coercionKind and coercionRole, we see that in order to find the Role
-for an NthCo, we have to know the kind; unfortunately, calculating the coercion
-kind for a nested NthCo is quadratic in the nesting depth, so we would like to
-avoid doing that as much as possible. To this end, we calculate the Role at
-construction time, and store it in the NthCo itself, thus removing the need to
-do the calculation on the fly.
-
-See Trac #11735 for the discussion that led to this.
+Why do we cache the role of NthCo in the NthCo constructor?
+Because computing role(Nth i co) involves figuring out that
+
+  co :: T tys1 ~ T tys2
+
+using coercionKind, and finding (coercionRole co), and then looking
+at the tyConRoles of T. Avoiding bad asymptotic behaviour here means
+we have to compute the kind and role of a coercion simultaneously,
+which makes the code complicated and inefficient.
+
+This only happens for NthCo. Caching the role solves the problem, and
+allows coercionKind and coercionRole to be simple.
+
+See Trac #11735
 
 Note [InstCo roles]
 ~~~~~~~~~~~~~~~~~~~


From git at git.haskell.org  Tue Mar 27 14:28:39 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 27 Mar 2018 14:28:39 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4394: Make mkNthCo take a Role parameter.
 (e1cf008)
Message-ID: <20180327142839.E8F213A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/tdammers/D4394
Link       : http://ghc.haskell.org/trac/ghc/changeset/e1cf008ad024fe705330aa755d6cb7a84305a689/ghc

>---------------------------------------------------------------

commit e1cf008ad024fe705330aa755d6cb7a84305a689
Author: Richard Eisenberg <rae at cs.brynmawr.edu>
Date:   Fri Jan 26 22:09:33 2018 -0500

    Make mkNthCo take a Role parameter.
    
    Most callers of mkNthCo know the role of the coercion they
    are trying to make. So instead of calculating this role, just
    pass it in.


>---------------------------------------------------------------

e1cf008ad024fe705330aa755d6cb7a84305a689
 compiler/coreSyn/CoreLint.hs      |  11 ++-
 compiler/coreSyn/CoreOpt.hs       |  24 ++---
 compiler/coreSyn/CoreUtils.hs     |   4 +-
 compiler/iface/TcIface.hs         |   2 +-
 compiler/typecheck/TcCanonical.hs |   2 +-
 compiler/typecheck/TcEvidence.hs  |  11 ++-
 compiler/typecheck/TcUnify.hs     |   4 +-
 compiler/types/Coercion.hs        | 201 ++++++++++++++++++++++++++------------
 compiler/types/Coercion.hs-boot   |   2 +-
 compiler/types/OptCoercion.hs     | 109 +++++++++------------
 compiler/types/TyCoRep.hs         |  11 +--
 compiler/types/Type.hs            |   6 +-
 compiler/types/Unify.hs           |   4 +-
 13 files changed, 225 insertions(+), 166 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc e1cf008ad024fe705330aa755d6cb7a84305a689

From git at git.haskell.org  Tue Mar 27 14:28:37 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 27 Mar 2018 14:28:37 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4394: Refactored setNominalRole_maybe to
 avoid dragging role through recursion (4778e53)
Message-ID: <20180327142837.19E213A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/tdammers/D4394
Link       : http://ghc.haskell.org/trac/ghc/changeset/4778e539e329830a3f92ede95f0d68215102aa03/ghc

>---------------------------------------------------------------

commit 4778e539e329830a3f92ede95f0d68215102aa03
Author: Tobias Dammers <tdammers at gmail.com>
Date:   Mon Mar 5 12:34:30 2018 +0100

    Refactored setNominalRole_maybe to avoid dragging role through recursion


>---------------------------------------------------------------

4778e539e329830a3f92ede95f0d68215102aa03
 compiler/types/Coercion.hs | 66 ++++++++++++++++++++++++----------------------
 1 file changed, 35 insertions(+), 31 deletions(-)

diff --git a/compiler/types/Coercion.hs b/compiler/types/Coercion.hs
index f9fdf28..0c342a6 100644
--- a/compiler/types/Coercion.hs
+++ b/compiler/types/Coercion.hs
@@ -1078,37 +1078,41 @@ setNominalRole_maybe :: Role -- of input coercion
                      -> Coercion -> Maybe Coercion
 setNominalRole_maybe r co
   | r == Nominal = Just co
-setNominalRole_maybe _ (SubCo co)  = Just co
-setNominalRole_maybe _ (Refl _ ty) = Just $ Refl Nominal ty
-setNominalRole_maybe _ (TyConAppCo Representational tc cos)
-  = do { cos' <- zipWithM setNominalRole_maybe (tyConRolesX Representational tc) cos
-       ; return $ TyConAppCo Nominal tc cos' }
-setNominalRole_maybe _ (FunCo Representational co1 co2)
-  = do { co1' <- setNominalRole_maybe Representational co1
-       ; co2' <- setNominalRole_maybe Representational co2
-       ; return $ FunCo Nominal co1' co2'
-       }
-setNominalRole_maybe r (SymCo co)
-  = SymCo <$> setNominalRole_maybe r co
-setNominalRole_maybe r (TransCo co1 co2)
-  = TransCo <$> setNominalRole_maybe r co1 <*> setNominalRole_maybe r co2
-setNominalRole_maybe r (AppCo co1 co2)
-  = AppCo <$> setNominalRole_maybe r co1 <*> pure co2
-setNominalRole_maybe r (ForAllCo tv kind_co co)
-  = ForAllCo tv kind_co <$> setNominalRole_maybe r co
-setNominalRole_maybe _ (NthCo _r n co)
-  = NthCo Nominal n <$> setNominalRole_maybe (coercionRole co) co
-setNominalRole_maybe r (InstCo co arg)
-  = InstCo <$> setNominalRole_maybe r co <*> pure arg
-setNominalRole_maybe r (CoherenceCo co1 co2)
-  = CoherenceCo <$> setNominalRole_maybe r co1 <*> pure co2
-setNominalRole_maybe _ (UnivCo prov _ co1 co2)
-  | case prov of UnsafeCoerceProv -> True   -- it's always unsafe
-                 PhantomProv _    -> False  -- should always be phantom
-                 ProofIrrelProv _ -> True   -- it's always safe
-                 PluginProv _     -> False  -- who knows? This choice is conservative.
-  = Just $ UnivCo prov Nominal co1 co2
-setNominalRole_maybe _ _ = Nothing
+  | otherwise = setNominalRole_maybe_helper co
+  where
+    setNominalRole_maybe_helper (SubCo co)  = Just co
+    setNominalRole_maybe_helper (Refl _ ty) = Just $ Refl Nominal ty
+    setNominalRole_maybe_helper (TyConAppCo Representational tc cos)
+      = do { cos' <- zipWithM setNominalRole_maybe (tyConRolesX Representational tc) cos
+           ; return $ TyConAppCo Nominal tc cos' }
+    setNominalRole_maybe_helper (FunCo Representational co1 co2)
+      = do { co1' <- setNominalRole_maybe Representational co1
+           ; co2' <- setNominalRole_maybe Representational co2
+           ; return $ FunCo Nominal co1' co2'
+           }
+    setNominalRole_maybe_helper (SymCo co)
+      = SymCo <$> setNominalRole_maybe_helper co
+    setNominalRole_maybe_helper (TransCo co1 co2)
+      = TransCo <$> setNominalRole_maybe_helper co1 <*> setNominalRole_maybe_helper co2
+    setNominalRole_maybe_helper (AppCo co1 co2)
+      = AppCo <$> setNominalRole_maybe_helper co1 <*> pure co2
+    setNominalRole_maybe_helper (ForAllCo tv kind_co co)
+      = ForAllCo tv kind_co <$> setNominalRole_maybe_helper co
+    setNominalRole_maybe_helper (NthCo _r n co)
+      -- NB, this case recurses via setNominalRole_maybe, not
+      -- setNominalRole_maybe_helper!
+      = NthCo Nominal n <$> setNominalRole_maybe (coercionRole co) co
+    setNominalRole_maybe_helper (InstCo co arg)
+      = InstCo <$> setNominalRole_maybe_helper co <*> pure arg
+    setNominalRole_maybe_helper (CoherenceCo co1 co2)
+      = CoherenceCo <$> setNominalRole_maybe_helper co1 <*> pure co2
+    setNominalRole_maybe_helper (UnivCo prov _ co1 co2)
+      | case prov of UnsafeCoerceProv -> True   -- it's always unsafe
+                     PhantomProv _    -> False  -- should always be phantom
+                     ProofIrrelProv _ -> True   -- it's always safe
+                     PluginProv _     -> False  -- who knows? This choice is conservative.
+      = Just $ UnivCo prov Nominal co1 co2
+    setNominalRole_maybe_helper _ = Nothing
 
 -- | Make a phantom coercion between two types. The coercion passed
 -- in must be a nominal coercion between the kinds of the


From git at git.haskell.org  Tue Mar 27 14:28:42 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 27 Mar 2018 14:28:42 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4394: Tighten cached role in NthCo
 (81882a7)
Message-ID: <20180327142842.C173D3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/tdammers/D4394
Link       : http://ghc.haskell.org/trac/ghc/changeset/81882a752b8b72c2c68dcc2b3ec546af4c5fbc94/ghc

>---------------------------------------------------------------

commit 81882a752b8b72c2c68dcc2b3ec546af4c5fbc94
Author: Richard Eisenberg <rae at cs.brynmawr.edu>
Date:   Mon Feb 12 13:02:23 2018 -0500

    Tighten cached role in NthCo


>---------------------------------------------------------------

81882a752b8b72c2c68dcc2b3ec546af4c5fbc94
 compiler/coreSyn/CoreLint.hs     |   9 +--
 compiler/coreSyn/CoreUtils.hs    |   2 +-
 compiler/iface/TcIface.hs        |   3 +-
 compiler/iface/ToIface.hs        |   2 +-
 compiler/typecheck/TcEvidence.hs |   3 +-
 compiler/types/Coercion.hs       | 168 ++++++++++++++++++++++-----------------
 compiler/types/Coercion.hs-boot  |   2 +-
 compiler/types/OptCoercion.hs    |  20 ++---
 compiler/types/TyCoRep.hs        |   6 +-
 docs/core-spec/CoreLint.ott      |   5 +-
 10 files changed, 115 insertions(+), 105 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc 81882a752b8b72c2c68dcc2b3ec546af4c5fbc94

From git at git.haskell.org  Tue Mar 27 14:28:45 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 27 Mar 2018 14:28:45 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4394: Fix test to reflect changed NthCo
 ctor (ca242c2)
Message-ID: <20180327142845.8B23E3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/tdammers/D4394
Link       : http://ghc.haskell.org/trac/ghc/changeset/ca242c2b8f6543f7af0f40926c1d547c37aace32/ghc

>---------------------------------------------------------------

commit ca242c2b8f6543f7af0f40926c1d547c37aace32
Author: Tobias Dammers <tdammers at gmail.com>
Date:   Tue Mar 13 13:59:36 2018 +0100

    Fix test to reflect changed NthCo ctor


>---------------------------------------------------------------

ca242c2b8f6543f7af0f40926c1d547c37aace32
 testsuite/tests/pmcheck/should_compile/T11195.hs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/testsuite/tests/pmcheck/should_compile/T11195.hs b/testsuite/tests/pmcheck/should_compile/T11195.hs
index 236932e..0c35b4f 100644
--- a/testsuite/tests/pmcheck/should_compile/T11195.hs
+++ b/testsuite/tests/pmcheck/should_compile/T11195.hs
@@ -62,7 +62,7 @@ opt_transList :: InScopeSet -> [NormalCo] -> [NormalCo] -> [NormalCo]
 opt_transList is = zipWith (opt_trans is)
 
 opt_trans_rule :: InScopeSet -> NormalNonIdCo -> NormalNonIdCo -> Maybe NormalCo
-opt_trans_rule is in_co1@(NthCo d1 co1) in_co2@(NthCo d2 co2)
+opt_trans_rule is in_co1@(NthCo r1 d1 co1) in_co2@(NthCo r2 d2 co2)
   | d1 == d2
   , co1 `compatible_co` co2 = undefined
 


From git at git.haskell.org  Tue Mar 27 14:28:48 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 27 Mar 2018 14:28:48 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4394: Fix rebasing mistake (89b8764)
Message-ID: <20180327142848.56A713A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/tdammers/D4394
Link       : http://ghc.haskell.org/trac/ghc/changeset/89b87640de8887af9421d88353896551d89bd5ee/ghc

>---------------------------------------------------------------

commit 89b87640de8887af9421d88353896551d89bd5ee
Author: Tobias Dammers <tdammers at gmail.com>
Date:   Tue Mar 20 17:08:01 2018 +0100

    Fix rebasing mistake


>---------------------------------------------------------------

89b87640de8887af9421d88353896551d89bd5ee
 compiler/types/TyCoRep.hs | 4 ----
 libraries/array           | 2 +-
 2 files changed, 1 insertion(+), 5 deletions(-)

diff --git a/compiler/types/TyCoRep.hs b/compiler/types/TyCoRep.hs
index 48b5151..abc932c 100644
--- a/compiler/types/TyCoRep.hs
+++ b/compiler/types/TyCoRep.hs
@@ -904,10 +904,6 @@ data Coercion
   | SymCo Coercion             -- :: e -> e
   | TransCo Coercion Coercion  -- :: e -> e -> e
 
-    -- The number coercions should match exactly the expectations
-    -- of the CoAxiomRule (i.e., the rule is fully saturated).
-  | AxiomRuleCo CoAxiomRule [Coercion]
-
   | NthCo  Role Int Coercion     -- Zero-indexed; decomposes (T t0 ... tn)
     -- :: "e" -> _ -> e0 -> e (inverse of TyConAppCo, see Note [TyConAppCo roles])
     -- Using NthCo on a ForAllCo gives an N coercion always
diff --git a/libraries/array b/libraries/array
index 1d0435f..9d63218 160000
--- a/libraries/array
+++ b/libraries/array
@@ -1 +1 @@
-Subproject commit 1d0435f4937f03901e32304e279f46ce19b0f089
+Subproject commit 9d63218fd067ff4885c0efa43b388238421a5c89


From git at git.haskell.org  Tue Mar 27 14:28:51 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 27 Mar 2018 14:28:51 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4394: Documented invariant on cached
 roles (1ef2070)
Message-ID: <20180327142851.1FD2F3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/tdammers/D4394
Link       : http://ghc.haskell.org/trac/ghc/changeset/1ef2070b30258e40c1f651d6959e89c680b06d98/ghc

>---------------------------------------------------------------

commit 1ef2070b30258e40c1f651d6959e89c680b06d98
Author: Tobias Dammers <tdammers at gmail.com>
Date:   Wed Feb 7 13:45:01 2018 +0100

    Documented invariant on cached roles


>---------------------------------------------------------------

1ef2070b30258e40c1f651d6959e89c680b06d98
 compiler/types/TyCoRep.hs | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/compiler/types/TyCoRep.hs b/compiler/types/TyCoRep.hs
index cd295f7..1b25e0c 100644
--- a/compiler/types/TyCoRep.hs
+++ b/compiler/types/TyCoRep.hs
@@ -912,7 +912,11 @@ data Coercion
     -- :: "e" _ -> e0 -> e (inverse of TyConAppCo, see Note [TyConAppCo roles])
     -- Using NthCo on a ForAllCo gives an N coercion always
     -- See Note [NthCo and newtypes]
+    --
+    -- Invariant:  (NthCo r i co), it is always the case that r = role of (Nth i co)
+    -- That is: the role of the entire coercion is redundantly cached here.
     -- See Note [NthCo Cached Roles]
+    --
     -- The Role might be more permissive than otherwise possible. That is, even
     -- if the Coercion inside is Nominal, the role could be Representational
     -- (it's like using a SubCo)


From git at git.haskell.org  Tue Mar 27 14:28:53 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 27 Mar 2018 14:28:53 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4394: Fixed unused variables (1dd3f7c)
Message-ID: <20180327142853.DBF6C3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/tdammers/D4394
Link       : http://ghc.haskell.org/trac/ghc/changeset/1dd3f7c0f878a1a042a0025baa8b66defb4aac73/ghc

>---------------------------------------------------------------

commit 1dd3f7c0f878a1a042a0025baa8b66defb4aac73
Author: Tobias Dammers <tdammers at gmail.com>
Date:   Mon Mar 5 15:18:41 2018 +0100

    Fixed unused variables


>---------------------------------------------------------------

1dd3f7c0f878a1a042a0025baa8b66defb4aac73
 compiler/types/Coercion.hs | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/compiler/types/Coercion.hs b/compiler/types/Coercion.hs
index 6dff0e7..a85ecdd 100644
--- a/compiler/types/Coercion.hs
+++ b/compiler/types/Coercion.hs
@@ -850,8 +850,8 @@ mkNthCo r n co
     good_call
       -- If the Coercion passed in is between forall-types, then the Int must
       -- be 0 and the role must be Nominal.
-      | Just (tv1, _) <- splitForAllTy_maybe ty1
-      , Just (tv2, _) <- splitForAllTy_maybe ty2
+      | Just (_tv1, _) <- splitForAllTy_maybe ty1
+      , Just (_tv2, _) <- splitForAllTy_maybe ty2
       = n == 0 && r == Nominal
 
       -- If the Coercion passed in is between T tys and T tys', then the Int
@@ -1312,12 +1312,12 @@ mkCoCast c g
        -- g1 :: s1 ~# s2
        -- g2 :: t1 ~# t2
     (tc, _) = splitTyConApp (pFst $ coercionKind g)
-    (n_args, role)
-      | tc `hasKey` eqPrimTyConKey     = (4, Nominal)
-      | tc `hasKey` eqReprPrimTyConKey = (4, Representational)
-      | tc `hasKey` eqTyConKey         = (3, Nominal)
-      | tc `hasKey` heqTyConKey        = (4, Nominal)
-      | tc `hasKey` coercibleTyConKey  = (3, Representational)
+    n_args
+      | tc `hasKey` eqPrimTyConKey     = 4
+      | tc `hasKey` eqReprPrimTyConKey = 4
+      | tc `hasKey` eqTyConKey         = 3
+      | tc `hasKey` heqTyConKey        = 4
+      | tc `hasKey` coercibleTyConKey  = 3
       | otherwise                      = pprPanic "mkCoCast" (ppr g $$ ppr (coercionKind g))
     co_list = decomposeCo (tyConArity tc) g (tyConRolesRepresentational tc)
     g1 = co_list `getNth` (n_args - 2)


From git at git.haskell.org  Tue Mar 27 14:28:56 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 27 Mar 2018 14:28:56 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4394: Fixes to Coercion.hs (504ac02)
Message-ID: <20180327142856.AB8E73A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/tdammers/D4394
Link       : http://ghc.haskell.org/trac/ghc/changeset/504ac026b4d226c5c34753997c1c3b94162ef1e2/ghc

>---------------------------------------------------------------

commit 504ac026b4d226c5c34753997c1c3b94162ef1e2
Author: Tobias Dammers <tdammers at gmail.com>
Date:   Mon Mar 5 11:20:34 2018 +0100

    Fixes to Coercion.hs


>---------------------------------------------------------------

504ac026b4d226c5c34753997c1c3b94162ef1e2
 compiler/types/Coercion.hs | 19 ++++++++++---------
 1 file changed, 10 insertions(+), 9 deletions(-)

diff --git a/compiler/types/Coercion.hs b/compiler/types/Coercion.hs
index 80b9af1..40dfd9a 100644
--- a/compiler/types/Coercion.hs
+++ b/compiler/types/Coercion.hs
@@ -839,16 +839,17 @@ mkTransCo co1 co2       = TransCo co1 co2
 mkNthCo :: HasDebugCallStack
         => Role  -- the role of the coercion you're creating
         -> Int
-				-> Coercion
-				-> Coercion
+        -> Coercion
+        -> Coercion
 mkNthCo r n co
   = ASSERT(good_call)
     go r n co
   where
-		(ty1, ty2) = coercionKind co
+    Pair ty1 ty2 = coercionKind co
+
     good_call
-		  -- If the Coercion passed in is between forall-types, then the Int must
-		  -- be 0 and the role must be Nominal.
+      -- If the Coercion passed in is between forall-types, then the Int must
+      -- be 0 and the role must be Nominal.
       | Just (tv1, _) <- splitForAllTy_maybe ty1
       , Just (tv2, _) <- splitForAllTy_maybe ty2
       = n == 0 && r == Nominal
@@ -865,8 +866,8 @@ mkNthCo r n co
       -- See also Note [NthCo Cached Roles] if you're wondering why it's
       -- blaringly obvious that we should be *computing* this role instead of
       -- passing it in.
-      | Just (tc1, tys1) <- splitTyConnApp_maybe ty1
-      , Just (tc2, tys1) <- splitForAllTy_maybe ty2
+      | Just (tc1, tys1) <- splitTyConApp_maybe ty1
+      , Just (tc2, tys2) <- splitTyConApp_maybe ty2
       , tc1 == tc2
       = let len1 = length tys1
             len2 = length tys2
@@ -877,7 +878,7 @@ mkNthCo r n co
         in len1 == len2 && n < len1 && good_role
 
       | otherwise
-			= True
+      = True
 
     go r 0 (Refl _ ty)
       | Just (tv, _) <- splitForAllTy_maybe ty
@@ -929,7 +930,7 @@ mkNthCo r n co
                                                             , ppr r ]) )
                                              arg_cos `getNth` n
 
-    mkNthCo r n co =
+    go r n co =
       NthCo r n co
 
 -- | If you're about to call @mkNthCo r n co@, then @r@ should be


From git at git.haskell.org  Tue Mar 27 14:28:59 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 27 Mar 2018 14:28:59 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4394: Removed dead code (0a8a117)
Message-ID: <20180327142859.6E5EF3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/tdammers/D4394
Link       : http://ghc.haskell.org/trac/ghc/changeset/0a8a1172d84f59ec01d792e44b9f7d0e34a7066b/ghc

>---------------------------------------------------------------

commit 0a8a1172d84f59ec01d792e44b9f7d0e34a7066b
Author: Tobias Dammers <tdammers at gmail.com>
Date:   Mon Mar 5 12:09:17 2018 +0100

    Removed dead code


>---------------------------------------------------------------

0a8a1172d84f59ec01d792e44b9f7d0e34a7066b
 compiler/types/Coercion.hs | 7 +------
 1 file changed, 1 insertion(+), 6 deletions(-)

diff --git a/compiler/types/Coercion.hs b/compiler/types/Coercion.hs
index 40dfd9a..f9fdf28 100644
--- a/compiler/types/Coercion.hs
+++ b/compiler/types/Coercion.hs
@@ -13,7 +13,7 @@ module Coercion (
         Coercion, CoercionN, CoercionR, CoercionP,
         UnivCoProvenance, CoercionHole, LeftOrRight(..),
         Var, CoVar, TyCoVar,
-        Role(..), ltRole, lteRole,
+        Role(..), ltRole,
 
         -- ** Functions over coercions
         coVarTypes, coVarKind, coVarKindsTypesRole, coVarRole,
@@ -1153,11 +1153,6 @@ ltRole Representational _       = False
 ltRole Nominal          Nominal = False
 ltRole Nominal          _       = True
 
-lteRole :: Role -> Role -> Bool
--- Is one role <= the other?
--- Nominal < Representational < Phantom
-lteRole r1 r2 = r1 == r2 || r1 `ltRole` r2
-
 -------------------------------
 
 -- | like mkKindCo, but aggressively & recursively optimizes to avoid using


From git at git.haskell.org  Tue Mar 27 14:29:02 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 27 Mar 2018 14:29:02 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4394: Refactor mkCoCast (3325ade)
Message-ID: <20180327142902.6A0493A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/tdammers/D4394
Link       : http://ghc.haskell.org/trac/ghc/changeset/3325ade4a58b05f102f0ecafb0732d18f705a4d0/ghc

>---------------------------------------------------------------

commit 3325ade4a58b05f102f0ecafb0732d18f705a4d0
Author: Tobias Dammers <tdammers at gmail.com>
Date:   Tue Mar 6 12:09:56 2018 +0100

    Refactor mkCoCast
    
    Get rid of ugly case pattern matching in favor of simply getting the
    last two arguments unconditionally.


>---------------------------------------------------------------

3325ade4a58b05f102f0ecafb0732d18f705a4d0
 compiler/types/Coercion.hs | 19 +++++++------------
 1 file changed, 7 insertions(+), 12 deletions(-)

diff --git a/compiler/types/Coercion.hs b/compiler/types/Coercion.hs
index a85ecdd..6e6f07c 100644
--- a/compiler/types/Coercion.hs
+++ b/compiler/types/Coercion.hs
@@ -1306,22 +1306,17 @@ mkPiCo r v co | isTyVar v = mkHomoForAllCos [v] co
 -- itself always representational.
 mkCoCast :: Coercion -> CoercionR -> Coercion
 mkCoCast c g
+  | (g2:g1:_) <- reverse co_list
   = mkSymCo g1 `mkTransCo` c `mkTransCo` g2
+
+  | otherwise
+  = pprPanic "mkCoCast" (ppr g $$ ppr (coercionKind g))
   where
-       -- g  :: (s1 ~# t1) ~# (s2 ~# t2)
-       -- g1 :: s1 ~# s2
-       -- g2 :: t1 ~# t2
+    -- g  :: (s1 ~# t1) ~# (s2 ~# t2)
+    -- g1 :: s1 ~# s2
+    -- g2 :: t1 ~# t2
     (tc, _) = splitTyConApp (pFst $ coercionKind g)
-    n_args
-      | tc `hasKey` eqPrimTyConKey     = 4
-      | tc `hasKey` eqReprPrimTyConKey = 4
-      | tc `hasKey` eqTyConKey         = 3
-      | tc `hasKey` heqTyConKey        = 4
-      | tc `hasKey` coercibleTyConKey  = 3
-      | otherwise                      = pprPanic "mkCoCast" (ppr g $$ ppr (coercionKind g))
     co_list = decomposeCo (tyConArity tc) g (tyConRolesRepresentational tc)
-    g1 = co_list `getNth` (n_args - 2)
-    g2 = co_list `getNth` (n_args - 1)
 
 {-
 %************************************************************************


From git at git.haskell.org  Tue Mar 27 14:29:05 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 27 Mar 2018 14:29:05 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4394: NthCo handling,
 assertions and documentation improvements (32c70f9)
Message-ID: <20180327142905.32F603A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/tdammers/D4394
Link       : http://ghc.haskell.org/trac/ghc/changeset/32c70f95c4e9171278a00af50e11cd7f43021295/ghc

>---------------------------------------------------------------

commit 32c70f95c4e9171278a00af50e11cd7f43021295
Author: Tobias Dammers <tdammers at gmail.com>
Date:   Sun Mar 4 21:07:13 2018 +0100

    NthCo handling, assertions and documentation improvements


>---------------------------------------------------------------

32c70f95c4e9171278a00af50e11cd7f43021295
 compiler/types/Coercion.hs | 160 +++++++++++++++++++++++++++------------------
 1 file changed, 95 insertions(+), 65 deletions(-)

diff --git a/compiler/types/Coercion.hs b/compiler/types/Coercion.hs
index 95c6426..80b9af1 100644
--- a/compiler/types/Coercion.hs
+++ b/compiler/types/Coercion.hs
@@ -231,7 +231,8 @@ where co_rep1, co_rep2 are the coercions on the representations.
 -- > decomposeCo 3 c [r1, r2, r3] = [nth r1 0 c, nth r2 1 c, nth r3 2 c]
 decomposeCo :: Arity -> Coercion
             -> [Role]  -- the roles of the output coercions
-                       -- this must have at least as many entries as the Arity provided
+                       -- this must have at least as many
+                       -- entries as the Arity provided
             -> [Coercion]
 decomposeCo arity co rs
   = [mkNthCo r n co | (n,r) <- [0..(arity-1)] `zip` rs ]
@@ -837,70 +838,99 @@ mkTransCo co1 co2       = TransCo co1 co2
 
 mkNthCo :: HasDebugCallStack
         => Role  -- the role of the coercion you're creating
-        -> Int -> Coercion -> Coercion
--- If the Coercion passed in is between forall-types, then the Int must
--- be 0 and the role must be Nominal. If the Coercion passed in is between
--- T tys and T tys', then the Int must be less than the length of tys/tys'
--- (which must be the same lengths). If the role of the Coercion is
--- nominal, then the role passed in must be nominal. If the role of the
--- Coercion is representational, then the role passed in must be
--- tyConRolesRepresentational T !! n. If the role of the Coercion
--- is Phantom, then the role passed in must be Phantom.
--- See also Note [NthCo Cached Roles] if you're wondering why it's
--- blaringly obvious that we should be *computing* this role instead
--- of passing it in.
-mkNthCo r 0 (Refl _ ty)
-  | Just (tv, _) <- splitForAllTy_maybe ty
-  = ASSERT( r == Nominal )
-    Refl r (tyVarKind tv)
-mkNthCo r n (Refl r0 ty)
-  = ASSERT2( ok_tc_app ty n, ppr n $$ ppr ty )
-    ASSERT( nthRole r0 tc n == r )
-    mkReflCo r (tyConAppArgN n ty)
-  where tc = tyConAppTyCon ty
-
-        ok_tc_app :: Type -> Int -> Bool
-        ok_tc_app ty n
-          | Just (_, tys) <- splitTyConApp_maybe ty
-          = tys `lengthExceeds` n
-          | isForAllTy ty  -- nth:0 pulls out a kind coercion from a hetero forall
-          = n == 0
-          | otherwise
-          = False
-
-mkNthCo r 0 (ForAllCo _ kind_co _)
-  = ASSERT( r == Nominal )
-    kind_co
-  -- If co :: (forall a1:k1. t1) ~ (forall a2:k2. t2)
-  -- then (nth 0 co :: k1 ~N k2)
-
-mkNthCo r n co@(FunCo r0 arg res)
-  -- See Note [Function coercions]
-  -- If FunCo _ arg_co res_co ::   (s1:TYPE sk1 -> s2:TYPE sk2)
-  --                             ~ (t1:TYPE tk1 -> t2:TYPE tk2)
-  -- Then we want to behave as if co was
-  --    TyConAppCo argk_co resk_co arg_co res_co
-  -- where
-  --    argk_co :: sk1 ~ tk1  =  mkNthCo 0 (mkKindCo arg_co)
-  --    resk_co :: sk2 ~ tk2  =  mkNthCo 0 (mkKindCo res_co)
-  --                             i.e. mkRuntimeRepCo
-  = case n of
-      0 -> ASSERT( r == Nominal ) mkRuntimeRepCo arg
-      1 -> ASSERT( r == Nominal ) mkRuntimeRepCo res
-      2 -> ASSERT( r == r0 )      arg
-      3 -> ASSERT( r == r0 )      res
-      _ -> pprPanic "mkNthCo(FunCo)" (ppr n $$ ppr co)
-
-mkNthCo r n (TyConAppCo r0 tc arg_cos) = ASSERT2( r == nthRole r0 tc n
-                                                , (vcat [ ppr tc
-                                                        , ppr arg_cos
-                                                        , ppr r0
-                                                        , ppr n
-                                                        , ppr r ]) )
-                                         arg_cos `getNth` n
-
-mkNthCo r n co =
-  NthCo r n co
+        -> Int
+				-> Coercion
+				-> Coercion
+mkNthCo r n co
+  = ASSERT(good_call)
+    go r n co
+  where
+		(ty1, ty2) = coercionKind co
+    good_call
+		  -- If the Coercion passed in is between forall-types, then the Int must
+		  -- be 0 and the role must be Nominal.
+      | Just (tv1, _) <- splitForAllTy_maybe ty1
+      , Just (tv2, _) <- splitForAllTy_maybe ty2
+      = n == 0 && r == Nominal
+
+      -- If the Coercion passed in is between T tys and T tys', then the Int
+      -- must be less than the length of tys/tys' (which must be the same
+      -- lengths).
+      --
+      -- If the role of the Coercion is nominal, then the role passed in must
+      -- be nominal. If the role of the Coercion is representational, then the
+      -- role passed in must be tyConRolesRepresentational T !! n. If the role
+      -- of the Coercion is Phantom, then the role passed in must be Phantom.
+      --
+      -- See also Note [NthCo Cached Roles] if you're wondering why it's
+      -- blaringly obvious that we should be *computing* this role instead of
+      -- passing it in.
+      | Just (tc1, tys1) <- splitTyConnApp_maybe ty1
+      , Just (tc2, tys1) <- splitForAllTy_maybe ty2
+      , tc1 == tc2
+      = let len1 = length tys1
+            len2 = length tys2
+            good_role = case coercionRole co of
+                          Nominal -> r == Nominal
+                          Representational -> r == (tyConRolesRepresentational tc1 !! n)
+                          Phantom -> r == Phantom
+        in len1 == len2 && n < len1 && good_role
+
+      | otherwise
+			= True
+
+    go r 0 (Refl _ ty)
+      | Just (tv, _) <- splitForAllTy_maybe ty
+      = ASSERT( r == Nominal )
+        Refl r (tyVarKind tv)
+    go r n (Refl r0 ty)
+      = ASSERT2( ok_tc_app ty n, ppr n $$ ppr ty )
+        ASSERT( nthRole r0 tc n == r )
+        mkReflCo r (tyConAppArgN n ty)
+      where tc = tyConAppTyCon ty
+
+            ok_tc_app :: Type -> Int -> Bool
+            ok_tc_app ty n
+              | Just (_, tys) <- splitTyConApp_maybe ty
+              = tys `lengthExceeds` n
+              | isForAllTy ty  -- nth:0 pulls out a kind coercion from a hetero forall
+              = n == 0
+              | otherwise
+              = False
+
+    go r 0 (ForAllCo _ kind_co _)
+      = ASSERT( r == Nominal )
+        kind_co
+      -- If co :: (forall a1:k1. t1) ~ (forall a2:k2. t2)
+      -- then (nth 0 co :: k1 ~N k2)
+
+    go r n co@(FunCo r0 arg res)
+      -- See Note [Function coercions]
+      -- If FunCo _ arg_co res_co ::   (s1:TYPE sk1 -> s2:TYPE sk2)
+      --                             ~ (t1:TYPE tk1 -> t2:TYPE tk2)
+      -- Then we want to behave as if co was
+      --    TyConAppCo argk_co resk_co arg_co res_co
+      -- where
+      --    argk_co :: sk1 ~ tk1  =  mkNthCo 0 (mkKindCo arg_co)
+      --    resk_co :: sk2 ~ tk2  =  mkNthCo 0 (mkKindCo res_co)
+      --                             i.e. mkRuntimeRepCo
+      = case n of
+          0 -> ASSERT( r == Nominal ) mkRuntimeRepCo arg
+          1 -> ASSERT( r == Nominal ) mkRuntimeRepCo res
+          2 -> ASSERT( r == r0 )      arg
+          3 -> ASSERT( r == r0 )      res
+          _ -> pprPanic "mkNthCo(FunCo)" (ppr n $$ ppr co)
+
+    go r n (TyConAppCo r0 tc arg_cos) = ASSERT2( r == nthRole r0 tc n
+                                                    , (vcat [ ppr tc
+                                                            , ppr arg_cos
+                                                            , ppr r0
+                                                            , ppr n
+                                                            , ppr r ]) )
+                                             arg_cos `getNth` n
+
+    mkNthCo r n co =
+      NthCo r n co
 
 -- | If you're about to call @mkNthCo r n co@, then @r@ should be
 -- whatever @nthCoRole n co@ returns.


From git at git.haskell.org  Tue Mar 27 14:29:07 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 27 Mar 2018 14:29:07 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4394: Another fix as per D4394 (d5b3da5)
Message-ID: <20180327142907.EF6563A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/tdammers/D4394
Link       : http://ghc.haskell.org/trac/ghc/changeset/d5b3da5fa054c1a159bbd7930e090b2f60515a04/ghc

>---------------------------------------------------------------

commit d5b3da5fa054c1a159bbd7930e090b2f60515a04
Author: Tobias Dammers <tdammers at gmail.com>
Date:   Mon Mar 5 12:50:35 2018 +0100

    Another fix as per D4394


>---------------------------------------------------------------

d5b3da5fa054c1a159bbd7930e090b2f60515a04
 compiler/types/Coercion.hs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/compiler/types/Coercion.hs b/compiler/types/Coercion.hs
index 0c342a6..6dff0e7 100644
--- a/compiler/types/Coercion.hs
+++ b/compiler/types/Coercion.hs
@@ -1319,7 +1319,7 @@ mkCoCast c g
       | tc `hasKey` heqTyConKey        = (4, Nominal)
       | tc `hasKey` coercibleTyConKey  = (3, Representational)
       | otherwise                      = pprPanic "mkCoCast" (ppr g $$ ppr (coercionKind g))
-    co_list = decomposeCo n_args g (replicate (n_args - 2) Nominal ++ repeat role)
+    co_list = decomposeCo (tyConArity tc) g (tyConRolesRepresentational tc)
     g1 = co_list `getNth` (n_args - 2)
     g2 = co_list `getNth` (n_args - 1)
 


From git at git.haskell.org  Tue Mar 27 14:29:10 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 27 Mar 2018 14:29:10 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4394: Caching coercion roles in NthCo and
 coercionKindsRole refactoring (#11735) (0683619)
Message-ID: <20180327142910.BC1AE3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/tdammers/D4394
Link       : http://ghc.haskell.org/trac/ghc/changeset/06836191c4133561b76cff1ae9f323d59ea71573/ghc

>---------------------------------------------------------------

commit 06836191c4133561b76cff1ae9f323d59ea71573
Author: Richard Eisenberg <rae at cs.brynmawr.edu>
Date:   Fri Jan 26 22:28:42 2018 -0500

    Caching coercion roles in NthCo and coercionKindsRole refactoring (#11735)
    
    Reviewers: goldfire, bgamari
    
    Subscribers: rwbarton, thomie, carter
    
    Differential Revision: https://phabricator.haskell.org/D4394


>---------------------------------------------------------------

06836191c4133561b76cff1ae9f323d59ea71573
 docs/core-spec/CoreLint.ott  |   5 +++--
 docs/core-spec/CoreSyn.ott   |   6 ++++--
 docs/core-spec/core-spec.mng |   2 +-
 docs/core-spec/core-spec.pdf | Bin 354307 -> 355707 bytes
 4 files changed, 8 insertions(+), 5 deletions(-)

diff --git a/docs/core-spec/CoreLint.ott b/docs/core-spec/CoreLint.ott
index 3a3468d..1fb9e09 100644
--- a/docs/core-spec/CoreLint.ott
+++ b/docs/core-spec/CoreLint.ott
@@ -299,12 +299,13 @@ G |-ty ti : k2'
 not (si is_a_coercion)
 not (ti is_a_coercion)
 R' = (tyConRolesX R T)[i]
+R' <= R0
 ---------------------- :: NthCoTyCon
-G |-co nth i g : si k2~R' k2' ti
+G |-co nth R0 i g : si k2~R0 k2' ti
 
 G |-co g : (forall z1_k1.t1) k3~R k4 (forall z2_k2.t2)
 --------------------------- :: NthCoForAll
-G |-co nth 0 g : k1 *~Nom * k2
+G |-co nth R0 0 g : k1 *~R0 * k2
 
 G |-co g : (s1 s2) k~Nom k' (t1 t2)
 G |-ty s1 : k1
diff --git a/docs/core-spec/CoreSyn.ott b/docs/core-spec/CoreSyn.ott
index 78118d5..e12f68b 100644
--- a/docs/core-spec/CoreSyn.ott
+++ b/docs/core-spec/CoreSyn.ott
@@ -152,8 +152,8 @@ g {{ tex \gamma }}, h {{ tex \eta }} :: 'Coercion_' ::= {{ com Coercions, \coder
   | g1 ; g2                 ::   :: TransCo       {{ com \ctor{TransCo}: Transitivity }}
   | mu </ ti // i /> $ </ gj // j />
                             ::   :: AxiomRuleCo   {{ com \ctor{AxiomRuleCo}: Axiom-rule application (for type-nats) }}
-  | nth I g                 ::   :: NthCo         {{ com \ctor{NthCo}: Projection (0-indexed) }}
-    {{ tex \textsf{nth}^{[[I]]}\,[[g]] }}
+  | nth R I g               ::   :: NthCo         {{ com \ctor{NthCo}: Projection (0-indexed) }}
+    {{ tex \textsf{nth}^{[[I]]}_{[[R]]}\,[[g]] }}
   | LorR g                  ::   :: LRCo          {{ com \ctor{LRCo}: Left/right projection }}
   | g @ h                   ::   :: InstCo        {{ com \ctor{InstCo}: Instantiation }}
   | g |> h                  ::   :: CoherenceCo   {{ com \ctor{CoherenceCo}: Coherence }}
@@ -453,6 +453,8 @@ formula :: 'formula_' ::=
   | role_list1 = role_list2            ::   :: eq_role_list
   | R1 /= R2                           ::   :: role_neq
   | R1 = R2                            ::   :: eq_role
+  | R1 <= R2                           ::   :: lte_role
+    {{ tex [[R1]] \leq [[R2]] }}
   | </ Ki // i /> = tyConDataCons T    ::   :: tyConDataCons
   | O ( n ) = R                        ::   :: role_lookup
   | R elt role_list                    ::   :: role_elt
diff --git a/docs/core-spec/core-spec.mng b/docs/core-spec/core-spec.mng
index 5800321..64e90bb 100644
--- a/docs/core-spec/core-spec.mng
+++ b/docs/core-spec/core-spec.mng
@@ -30,7 +30,7 @@ System FC, as implemented in GHC\footnote{This
 document was originally prepared by Richard Eisenberg (\texttt{eir at cis.upenn.edu}),
 but it should be maintained by anyone who edits the functions or data structures
 mentioned in this file. Please feel free to contact Richard for more information.}\\
-\Large 23 October, 2015
+\Large 26 January, 2018
 \end{center}
 
 \section{Introduction}
diff --git a/docs/core-spec/core-spec.pdf b/docs/core-spec/core-spec.pdf
index 1e13911..3732818 100644
Binary files a/docs/core-spec/core-spec.pdf and b/docs/core-spec/core-spec.pdf differ


From git at git.haskell.org  Tue Mar 27 14:29:13 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 27 Mar 2018 14:29:13 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4394: Increased allocation limit for
 T5321 on OS X (cf5cec3)
Message-ID: <20180327142913.85C8F3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/tdammers/D4394
Link       : http://ghc.haskell.org/trac/ghc/changeset/cf5cec3619ae52d2cd825a6f291deba251fbbfe6/ghc

>---------------------------------------------------------------

commit cf5cec3619ae52d2cd825a6f291deba251fbbfe6
Author: Tobias Dammers <tdammers at gmail.com>
Date:   Sat Mar 17 17:58:52 2018 +0100

    Increased allocation limit for T5321 on OS X


>---------------------------------------------------------------

cf5cec3619ae52d2cd825a6f291deba251fbbfe6
 testsuite/tests/perf/compiler/all.T | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/testsuite/tests/perf/compiler/all.T b/testsuite/tests/perf/compiler/all.T
index f9cf692..5a45859 100644
--- a/testsuite/tests/perf/compiler/all.T
+++ b/testsuite/tests/perf/compiler/all.T
@@ -549,6 +549,9 @@ test('T5321Fun',
              # 2016-04-06: 279922360 x86/Linux
              # 2017-03-24: 244387620 x86/Linux (64-bit machine)
 
+            (platform('x86_64-apple-darwin'), 446893600, 5),
+             # 2018-03-17: 423774560     #  OS X-only (reason unknown, see #11753)
+
             (wordsize(64), 423774560, 5)])
              # prev:       585521080
              # 2012-08-29: 713385808     #  (increase due to new codegen)


From git at git.haskell.org  Tue Mar 27 14:29:16 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 27 Mar 2018 14:29:16 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4394's head updated: Fix rebasing mistake
 (89b8764)
Message-ID: <20180327142916.5BE0C3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

Branch 'wip/tdammers/D4394' now includes:

     efc844f Fix over-eager constant folding in bitInteger
     034c32f Improve shortOutIndirections slightly
     d5577f4 Special-case record fields ending with hash when deriving Read
     affdea8 Allow PartialTypeSignatures in standalone deriving contexts
     ceb9147 Support adding objects from TH
     7bb1fde testsuite: Add test for #14931
     10566a8 Support iOS variants elsewhere when configuring
     9893042 Fix two pernicious bugs in DeriveAnyClass
     cf80995 Add Note [BLACKHOLE points to IND]
     f7bbc34 Run C finalizers incrementally during mutation
     fb462f9 Fix panic on module re-exports of DuplicateRcordFields
     c16df60 document: fix trac issue #14229
     9a00bfb rts/RetainerProfile: Dump closure type if push() fails
     0703c00 testsuite: Add test for #14925
     20f14b4 Fix #14916 with an additional validity check in deriveTyData
     0cbb13b Don't refer to blocks in debug info when -g1
     a3986d7 Fix scoped type variables in TH for several constructs
     41db237 llvmGen: Pass -optlo flags last to opt
     20ae19f base: Fix Unicode handling of TyCon's Show instance
     ecfb4d3 Add new debugging flag -dinline-check
     efd70cf Add unaligned bytearray access primops. Fixes #4442.
     d152dab Add a job running on Fedora
     60e29dc circleci: Bump Hackage index state
     f0b258b rts, base: Refactor stats.c to improve --machine-readable report
     41c1558 Make it evident in types that StgLam can't have empty args
     97e1f30 Fix compilation stopper on macOS with -Werror
     e3dbb44 Fix #12919 by making the flattener homegeneous.
     b47a6c3 Fix performance of flattener patch (#12919)
     f13a0fc Comments only
     1fce2c3 Avoid quadratic complexity in typeKind
     71d50db Minor refactor and commments
     9cc6a18 White space only
     a7628dc Deal with join points with RULES
     3ebf05f Fix the test for #13938
     8cfd2e4 configure: Throw error if OS is found to be msys
     d5c4d46 CmmPipeline: add a second pass of CmmCommonBlockElim
     d1fb583 testsuite: Add test for #14965
     ab9e986 rts: Fix profiled build after D4529
     4e9fa93 Applying patch suggested in #11735 to improve coercionKind perf
     0019570 Added SCCs to hunt down #14683
     fcc65df Refactored coercionKindsRole (as per #11735)
     2adc093 Simplification as per #11735
     85e4b46 Caching coercion roles in NthCo (#11735)
     e1cf008 Make mkNthCo take a Role parameter.
     0683619 Caching coercion roles in NthCo and coercionKindsRole refactoring (#11735)
     7ef2f9c Fixed NthCo Note (discussion in D4385)
     1ef2070 Documented invariant on cached roles
     81882a7 Tighten cached role in NthCo
     32c70f9 NthCo handling, assertions and documentation improvements
     504ac02 Fixes to Coercion.hs
     0a8a117 Removed dead code
     4778e53 Refactored setNominalRole_maybe to avoid dragging role through recursion
     d5b3da5 Another fix as per D4394
     1dd3f7c Fixed unused variables
     3325ade Refactor mkCoCast
     ca242c2 Fix test to reflect changed NthCo ctor
     cf5cec3 Increased allocation limit for T5321 on OS X
     89b8764 Fix rebasing mistake

From git at git.haskell.org  Tue Mar 27 17:26:31 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Tue, 27 Mar 2018 17:26:31 +0000 (UTC)
Subject: [commit: ghc] master: More format string fixes (b58282a)
Message-ID: <20180327172631.317A93A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/b58282a009ae67cbd4befbe062452026c82afd51/ghc

>---------------------------------------------------------------

commit b58282a009ae67cbd4befbe062452026c82afd51
Author: Ben Gamari <ben at smart-cactus.org>
Date:   Tue Mar 27 09:57:01 2018 -0400

    More format string fixes


>---------------------------------------------------------------

b58282a009ae67cbd4befbe062452026c82afd51
 rts/Stats.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/rts/Stats.c b/rts/Stats.c
index 3efa6cc..1aea64f 100644
--- a/rts/Stats.c
+++ b/rts/Stats.c
@@ -949,11 +949,11 @@ static void report_machine_readable (const RTSSummaryStats * sum)
 #if defined(THREADED_RTS)
     MR_STAT("bound_task_count", FMT_Word32, sum->bound_task_count);
     MR_STAT("sparks_count", FMT_Word64, sum->sparks_count);
-    MR_STAT("sparks_converted", FMT_Word64, sum->sparks.converted);
-    MR_STAT("sparks_overflowed", FMT_Word64, sum->sparks.overflowed);
-    MR_STAT("sparks_dud ", FMT_Word64, sum->sparks.dud);
-    MR_STAT("sparks_gcd", FMT_Word64, sum->sparks.gcd);
-    MR_STAT("sparks_fizzled", FMT_Word64, sum->sparks.fizzled);
+    MR_STAT("sparks_converted", FMT_Word, sum->sparks.converted);
+    MR_STAT("sparks_overflowed", FMT_Word, sum->sparks.overflowed);
+    MR_STAT("sparks_dud ", FMT_Word, sum->sparks.dud);
+    MR_STAT("sparks_gcd", FMT_Word, sum->sparks.gcd);
+    MR_STAT("sparks_fizzled", FMT_Word, sum->sparks.fizzled);
     MR_STAT("work_balance", "f", sum->work_balance);
 
     // next, globals (other than internal counters)


From git at git.haskell.org  Wed Mar 28 17:43:06 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Wed, 28 Mar 2018 17:43:06 +0000 (UTC)
Subject: [commit: ghc] ghc-8.4: Fix two pernicious bugs in DeriveAnyClass
 (d8dbe29)
Message-ID: <20180328174306.DA24A3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : ghc-8.4
Link       : http://ghc.haskell.org/trac/ghc/changeset/d8dbe2936c923471a13e214113b0e43222e95592/ghc

>---------------------------------------------------------------

commit d8dbe2936c923471a13e214113b0e43222e95592
Author: Ryan Scott <ryan.gl.scott at gmail.com>
Date:   Sun Mar 25 14:00:39 2018 -0400

    Fix two pernicious bugs in DeriveAnyClass
    
    The way GHC was handling `DeriveAnyClass` was subtly wrong
    in two notable ways:
    
    * In `inferConstraintsDAC`, we were //always// bumping the `TcLevel`
      of newly created unification variables, under the assumption that
      we would always place those unification variables inside an
      implication constraint. But #14932 showed precisely the scenario
      where we had `DeriveAnyClass` //without// any of the generated
      constraints being used inside an implication, which made GHC
      incorrectly believe the unification variables were untouchable.
    * Even worse, we were using the generated unification variables from
      `inferConstraintsDAC` in every single iteration of `simplifyDeriv`.
      In #14933, however, we have a scenario where we fill in a
      unification variable with a skolem in one iteration, discard it,
      proceed on to another iteration, use the same unification variable
      (still filled in with the old skolem), and try to unify it with
      a //new// skolem! This results in an utter disaster.
    
    The root of both these problems is `inferConstraintsDAC`. This patch
    fixes the issue by no longer generating unification variables
    directly in `inferConstraintsDAC`. Instead, we store the original
    variables from a generic default type signature in `to_metas`, a new
    field of `ThetaOrigin`, and in each iteration of `simplifyDeriv`, we
    generate fresh meta tyvars (avoiding the second issue). Moreover,
    this allows us to more carefully fine-tune the `TcLevel` under which
    we create these meta tyvars, fixing the first issue.
    
    Test Plan: make test TEST="T14932 T14933"
    
    Reviewers: simonpj, bgamari
    
    Reviewed By: simonpj
    
    Subscribers: rwbarton, thomie, carter
    
    GHC Trac Issues: #14932, #14933
    
    Differential Revision: https://phabricator.haskell.org/D4507
    
    (cherry picked from commit 9893042604cda5260cb0f7b674ed5c34b419e403)


>---------------------------------------------------------------

d8dbe2936c923471a13e214113b0e43222e95592
 compiler/typecheck/TcDerivInfer.hs                | 103 ++++++++++++----------
 compiler/typecheck/TcDerivUtils.hs                |  97 +++++++++++++-------
 testsuite/tests/deriving/should_compile/T14932.hs |  23 +++++
 testsuite/tests/deriving/should_compile/T14933.hs |  22 +++++
 testsuite/tests/deriving/should_compile/all.T     |   2 +
 5 files changed, 170 insertions(+), 77 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc d8dbe2936c923471a13e214113b0e43222e95592

From git at git.haskell.org  Wed Mar 28 17:43:17 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Wed, 28 Mar 2018 17:43:17 +0000 (UTC)
Subject: [commit: ghc] ghc-8.4: Fix a nasty bug in the pure unifier (1132ec6)
Message-ID: <20180328174317.45E403A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : ghc-8.4
Link       : http://ghc.haskell.org/trac/ghc/changeset/1132ec683591eafa55e309cd01b9f4cb5524c7c5/ghc

>---------------------------------------------------------------

commit 1132ec683591eafa55e309cd01b9f4cb5524c7c5
Author: Simon Peyton Jones <simonpj at microsoft.com>
Date:   Mon Feb 26 17:44:55 2018 +0000

    Fix a nasty bug in the pure unifier
    
    The pure unifier was building an infinite type, through a defective
    occurs check.  So GHC went into an infinite loop.
    
    Reason: we were neglecting the 'kco' part of the type, which
    'unify_ty' maintains.  Yikes.
    
    The fix is easy.  I refactored a bit to make it harder to
    go wrong in future.
    
    (cherry picked from commit e99fdf775540440c1c58dc5ade3c5984dc49246f)


>---------------------------------------------------------------

1132ec683591eafa55e309cd01b9f4cb5524c7c5
 compiler/types/Unify.hs                 | 59 ++++++++++++++++++---------------
 testsuite/tests/polykinds/T14846.hs     | 39 ++++++++++++++++++++++
 testsuite/tests/polykinds/T14846.stderr | 43 ++++++++++++++++++++++++
 testsuite/tests/polykinds/all.T         |  1 +
 4 files changed, 116 insertions(+), 26 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc 1132ec683591eafa55e309cd01b9f4cb5524c7c5

From git at git.haskell.org  Wed Mar 28 17:44:50 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Wed, 28 Mar 2018 17:44:50 +0000 (UTC)
Subject: [commit: ghc] ghc-8.4: Bump xhtml submodule to 3000.2.2.1 (597ba9c)
Message-ID: <20180328174450.343A13A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : ghc-8.4
Link       : http://ghc.haskell.org/trac/ghc/changeset/597ba9c012d27f3a2695e6e09aafe8abb4f51c36/ghc

>---------------------------------------------------------------

commit 597ba9c012d27f3a2695e6e09aafe8abb4f51c36
Author: Ben Gamari <ben at smart-cactus.org>
Date:   Mon Mar 26 17:06:18 2018 -0400

    Bump xhtml submodule to 3000.2.2.1


>---------------------------------------------------------------

597ba9c012d27f3a2695e6e09aafe8abb4f51c36
 libraries/xhtml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libraries/xhtml b/libraries/xhtml
index c5c623e..721779a 160000
--- a/libraries/xhtml
+++ b/libraries/xhtml
@@ -1 +1 @@
-Subproject commit c5c623e497f13ec187e0d228e0e8a3d9ee39a715
+Subproject commit 721779acc35dccd6a43a292b24099b65d93d390c


From git at git.haskell.org  Wed Mar 28 17:45:00 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Wed, 28 Mar 2018 17:45:00 +0000 (UTC)
Subject: [commit: ghc] ghc-8.4: Bump Haddock submodule (199a088)
Message-ID: <20180328174500.8136C3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : ghc-8.4
Link       : http://ghc.haskell.org/trac/ghc/changeset/199a0887da5dda26f59cff13b3ad811defafb784/ghc

>---------------------------------------------------------------

commit 199a0887da5dda26f59cff13b3ad811defafb784
Author: Ben Gamari <ben at smart-cactus.org>
Date:   Mon Mar 26 17:07:01 2018 -0400

    Bump Haddock submodule


>---------------------------------------------------------------

199a0887da5dda26f59cff13b3ad811defafb784
 utils/haddock | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/utils/haddock b/utils/haddock
index d66092e..7064cd5 160000
--- a/utils/haddock
+++ b/utils/haddock
@@ -1 +1 @@
-Subproject commit d66092ee99639de628dbc4fce8a9936875f47d8c
+Subproject commit 7064cd54e016b2f8e0a8c2ba8d3dd5edea9071ca


From git at git.haskell.org  Wed Mar 28 17:45:14 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Wed, 28 Mar 2018 17:45:14 +0000 (UTC)
Subject: [commit: ghc] ghc-8.4: Bump Cabal submodule to 2.2.0.1 (a356469)
Message-ID: <20180328174514.9FD7C3A5F7@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : ghc-8.4
Link       : http://ghc.haskell.org/trac/ghc/changeset/a356469c0434e768502605d8313a80c4b1bb7f7c/ghc

>---------------------------------------------------------------

commit a356469c0434e768502605d8313a80c4b1bb7f7c
Author: Ben Gamari <ben at smart-cactus.org>
Date:   Wed Mar 28 13:13:36 2018 -0400

    Bump Cabal submodule to 2.2.0.1


>---------------------------------------------------------------

a356469c0434e768502605d8313a80c4b1bb7f7c
 libraries/Cabal | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libraries/Cabal b/libraries/Cabal
index ccd0c59..cc92108 160000
--- a/libraries/Cabal
+++ b/libraries/Cabal
@@ -1 +1 @@
-Subproject commit ccd0c59bec88b179c06b65df3247d8664b38e44e
+Subproject commit cc9210818ee674cd6eed42e7cdcafd710da4b64b


From git at git.haskell.org  Thu Mar 29 15:42:12 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Thu, 29 Mar 2018 15:42:12 +0000 (UTC)
Subject: [commit: ghc] master: rts: One last formatting string fix (88f06d4)
Message-ID: <20180329154212.EDEC73A5F8@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/88f06d41f76b342193c393b192a219715fb39ff9/ghc

>---------------------------------------------------------------

commit 88f06d41f76b342193c393b192a219715fb39ff9
Author: Ben Gamari <ben at smart-cactus.org>
Date:   Thu Mar 29 10:45:21 2018 -0400

    rts: One last formatting string fix


>---------------------------------------------------------------

88f06d41f76b342193c393b192a219715fb39ff9
 rts/Stats.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/rts/Stats.c b/rts/Stats.c
index 1aea64f..44b6e2d 100644
--- a/rts/Stats.c
+++ b/rts/Stats.c
@@ -716,7 +716,7 @@ static void report_summary(const RTSSummaryStats* sum)
                 peakWorkerCount, workerCount,
                 n_capabilities);
 
-    statsPrintf("  SPARKS: %" FMT_Word
+    statsPrintf("  SPARKS: %" FMT_Word64
                 "(%" FMT_Word " converted, %" FMT_Word " overflowed, %"
                 FMT_Word " dud, %" FMT_Word " GC'd, %" FMT_Word " fizzled)\n\n",
                 sum->sparks_count,


From git at git.haskell.org  Thu Mar 29 16:01:35 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Thu, 29 Mar 2018 16:01:35 +0000 (UTC)
Subject: [commit: ghc] master: Update Note [Documenting optimisation flags]
 (bf2b9cc)
Message-ID: <20180329160135.C01043A5F8@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/bf2b9ccc2f4147220b2307c93f90b895e1bea434/ghc

>---------------------------------------------------------------

commit bf2b9ccc2f4147220b2307c93f90b895e1bea434
Author: Simon Jakobi <simon.jakobi at gmail.com>
Date:   Thu Mar 29 12:07:17 2018 +0200

    Update Note [Documenting optimisation flags]


>---------------------------------------------------------------

bf2b9ccc2f4147220b2307c93f90b895e1bea434
 compiler/main/DynFlags.hs | 9 ++-------
 1 file changed, 2 insertions(+), 7 deletions(-)

diff --git a/compiler/main/DynFlags.hs b/compiler/main/DynFlags.hs
index ba4d281..7c27e52 100644
--- a/compiler/main/DynFlags.hs
+++ b/compiler/main/DynFlags.hs
@@ -4344,16 +4344,11 @@ impliedXFlags
 -- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 --
 -- If you change the list of flags enabled for particular optimisation levels
--- please remember to update the User's Guide. The relevant files are:
+-- please remember to update the User's Guide. The relevant file is:
 --
 --   docs/users_guide/using-optimisation.rst
 --
--- The first contains the Flag Reference section, which briefly lists all
--- available flags. The second contains a detailed description of the
--- flags. Both places should contain information whether a flag is implied by
--- -O0, -O or -O2.
---
--- (See #6087 about adding -flate-dmd-anal in this list)
+-- Make sure to note whether a flag is implied by -O0, -O or -O2.
 
 optLevelFlags :: [([Int], GeneralFlag)]
 optLevelFlags -- see Note [Documenting optimisation flags]


From git at git.haskell.org  Thu Mar 29 16:03:03 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Thu, 29 Mar 2018 16:03:03 +0000 (UTC)
Subject: [commit: ghc] master: Rename CI docker images (d06a5a9)
Message-ID: <20180329160303.860153A5F8@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/d06a5a9d435b048031aafe8ff6d7a740260a3e84/ghc

>---------------------------------------------------------------

commit d06a5a9d435b048031aafe8ff6d7a740260a3e84
Author: mrkkrp <markkarpov92 at gmail.com>
Date:   Tue Mar 20 14:23:07 2018 +0700

    Rename CI docker images
    
    Now we use the images from the ‘ghcci’ account on docker hub.


>---------------------------------------------------------------

d06a5a9d435b048031aafe8ff6d7a740260a3e84
 .circleci/config.yml | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/.circleci/config.yml b/.circleci/config.yml
index 182a66b..e42d849 100644
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -87,7 +87,7 @@ jobs:
   "validate-x86_64-linux":
     resource_class: xlarge
     docker:
-      - image: mrkkrp/ghcci-x86_64-linux:0.0.4
+      - image: ghcci/x86_64-linux:0.0.1
     environment:
       <<: *buildenv
     steps:
@@ -105,7 +105,7 @@ jobs:
   "validate-x86_64-freebsd":
     resource_class: xlarge
     docker:
-      - image: mrkkrp/ghcci-x86_64-freebsd
+      - image: ghcci/x86_64-freebsd
     environment:
       TARGET: FreeBSD
       <<: *buildenv
@@ -145,7 +145,7 @@ jobs:
   "validate-hadrian-x86_64-linux":
     resource_class: xlarge
     docker:
-      - image: mrkkrp/ghcci-x86_64-linux:0.0.4
+      - image: ghcci/x86_64-linux:0.0.1
     environment:
       <<: *buildenv
     steps:
@@ -159,7 +159,7 @@ jobs:
   "validate-x86_64-linux-unreg":
     resource_class: xlarge
     docker:
-      - image: mrkkrp/ghcci-x86_64-linux:0.0.4
+      - image: ghcci/x86_64-linux:0.0.1
     environment:
       <<: *buildenv
     steps:
@@ -174,7 +174,7 @@ jobs:
   "validate-x86_64-linux-llvm":
     resource_class: xlarge
     docker:
-      - image: mrkkrp/ghcci-x86_64-linux:0.0.4
+      - image: ghcci/x86_64-linux:0.0.1
     environment:
       <<: *buildenv
       BUILD_FLAVOUR: perf-llvm
@@ -199,7 +199,7 @@ jobs:
   "validate-x86_64-linux-debug":
     resource_class: xlarge
     docker:
-      - image: mrkkrp/ghcci-x86_64-linux:0.0.4
+      - image: ghcci/x86_64-linux:0.0.1
     environment:
       BUILD_FLAVOUR: devel2
       <<: *buildenv
@@ -215,7 +215,7 @@ jobs:
   "validate-i386-linux":
     resource_class: xlarge
     docker:
-      - image: mrkkrp/ghcci-i386-linux:0.0.1
+      - image: ghcci/i386-linux:0.0.1
     environment:
       <<: *buildenv
     steps:


From git at git.haskell.org  Thu Mar 29 16:03:17 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Thu, 29 Mar 2018 16:03:17 +0000 (UTC)
Subject: [commit: ghc] master: Full AppVeyor build with tests (0951e03)
Message-ID: <20180329160317.613C13A5F8@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/0951e03efe9492b01cea3bf59a7cb4a3baaea8bd/ghc

>---------------------------------------------------------------

commit 0951e03efe9492b01cea3bf59a7cb4a3baaea8bd
Author: mrkkrp <markkarpov92 at gmail.com>
Date:   Tue Mar 27 21:30:01 2018 +0700

    Full AppVeyor build with tests


>---------------------------------------------------------------

0951e03efe9492b01cea3bf59a7cb4a3baaea8bd
 .appveyor.sh | 26 ++++----------------------
 appveyor.yml |  3 ++-
 2 files changed, 6 insertions(+), 23 deletions(-)

diff --git a/.appveyor.sh b/.appveyor.sh
index b7fde23..97d0fdb 100644
--- a/.appveyor.sh
+++ b/.appveyor.sh
@@ -1,8 +1,8 @@
 # Configure the environment
 MSYSTEM=MINGW64
-THREADS=3
+THREADS=9
 SKIP_PERF_TESTS=YES
-BUILD_FLAVOUR=quick
+BUILD_FLAVOUR=
 source /etc/profile || true # a terrible, terrible workaround for msys2 brokenness
 
 # Don't set -e until after /etc/profile is sourced
@@ -11,45 +11,27 @@ cd $APPVEYOR_BUILD_FOLDER
 
 case "$1" in
     "prepare")
-        # Bring msys up-to-date
-        # However, we current don't do this: generally one must restart all
-        # msys2 processes when updating the msys2 runtime, which this may do. We can't
-        # easily do this and therefore do simply don't update.
-        #pacman --noconfirm -Syuu
-
-        # Install basic build dependencies
-        pacman --noconfirm -S --needed git tar bsdtar binutils autoconf make xz curl libtool automake python python2 p7zip patch mingw-w64-$(uname -m)-python3-sphinx mingw-w64-$(uname -m)-tools-git
-
         # Prepare the tree
         git config remote.origin.url git://github.com/ghc/ghc.git
         git config --global url."git://github.com/ghc/packages-".insteadOf git://github.com/ghc/packages/
         git submodule init
         git submodule --quiet update --recursive
-
-        # Install build dependencies
-        wget -q -O - https://downloads.haskell.org/~ghc/8.2.1/ghc-8.2.1-x86_64-unknown-mingw32.tar.xz | tar -xJ -C /mingw64 --strip-components=1
-        mkdir -p /usr/local/bin
-        wget -q -O - https://www.haskell.org/cabal/release/cabal-install-1.24.0.0/cabal-install-1.24.0.0-x86_64-unknown-mingw32.zip | bsdtar -xzf- -C /usr/local/bin
-        cabal update
-        cabal install -j --prefix=/usr/local alex happy
         ;;
-
     "build")
         # Build the compiler
         ./boot
-        ./configure --enable-tarballs-autodownload
         cat <<EOF >> mk/build.mk
         BuildFlavour=$BUILD_FLAVOUR
         ifneq "\$(BuildFlavour)" ""
         include mk/flavours/\$(BuildFlavour).mk
         endif
 EOF
+        ./configure --enable-tarballs-autodownload
         make -j$THREADS
         ;;
 
     "test")
-        # This does not finish in time.
-        # make fasttest THREADS=$THREADS
+        make test THREADS=$THREADS
         make binary-dist
         7z a ghc-windows.zip *.tar.xz
         ;;
diff --git a/appveyor.yml b/appveyor.yml
index bcf35a0..d7623e4 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -1,4 +1,6 @@
 version: "{build}"
+build_cloud: ghc-gce-cloud
+image: GHC-GCE
 
 build:
   verbosity: normal
@@ -12,7 +14,6 @@ environment:
     MSYSTEM: MINGW64
     BIT: 64
 
-os: Visual Studio 2015
 deploy: off
 
 install:


From git at git.haskell.org  Thu Mar 29 16:29:42 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Thu, 29 Mar 2018 16:29:42 +0000 (UTC)
Subject: [commit: ghc] ghc-8.4: Fix typo in user guide about ConstraintKinds
 (e261975)
Message-ID: <20180329162942.D89BB3A5F8@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : ghc-8.4
Link       : http://ghc.haskell.org/trac/ghc/changeset/e2619754ea766b82b197c982437abcff9cbb993e/ghc

>---------------------------------------------------------------

commit e2619754ea766b82b197c982437abcff9cbb993e
Author: Frank Steffahn <fdsteffahn at gmail.com>
Date:   Tue Mar 13 23:29:04 2018 +0100

    Fix typo in user guide about ConstraintKinds
    
    The backslash currently in this type signature makes no sense. Without it, the example is fine.
    
    (cherry picked from commit 960cd424fb2ca99389c8f041d519d661494d07c1)


>---------------------------------------------------------------

e2619754ea766b82b197c982437abcff9cbb993e
 docs/users_guide/glasgow_exts.rst | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/docs/users_guide/glasgow_exts.rst b/docs/users_guide/glasgow_exts.rst
index d2086f6..a0b5cdd 100644
--- a/docs/users_guide/glasgow_exts.rst
+++ b/docs/users_guide/glasgow_exts.rst
@@ -9241,7 +9241,7 @@ The following things have kind ``Constraint``:
 -  Anything whose form is not yet known, but the user has declared to
    have kind ``Constraint`` (for which they need to import it from
    ``GHC.Exts``). So for example
-   ``type Foo (f :: \* -> Constraint) = forall b. f b => b -> b``
+   ``type Foo (f :: * -> Constraint) = forall b. f b => b -> b``
    is allowed, as well as examples involving type families: ::
 
        type family Typ a b :: Constraint


From git at git.haskell.org  Thu Mar 29 16:29:52 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Thu, 29 Mar 2018 16:29:52 +0000 (UTC)
Subject: [commit: ghc] ghc-8.4: Revert "GHCi: Don't remove shadowed bindings
 from typechecker scope." (fbc4eba)
Message-ID: <20180329162952.8D6183A5F8@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : ghc-8.4
Link       : http://ghc.haskell.org/trac/ghc/changeset/fbc4ebafb052d0905543ca821801e77b86384db1/ghc

>---------------------------------------------------------------

commit fbc4ebafb052d0905543ca821801e77b86384db1
Author: Ömer Sinan Ağacan <omeragacan at gmail.com>
Date:   Thu Mar 8 21:42:22 2018 +0300

    Revert "GHCi: Don't remove shadowed bindings from typechecker scope."
    
    This reverts commit 59d7ee53906b9cee7f279c1f9567af7b930f8636 and enables
    the test for #14052.
    
    (See #14052 for the discussion)
    
    Reviewers: bgamari
    
    Reviewed By: bgamari
    
    Subscribers: rwbarton, thomie, carter
    
    GHC Trac Issues: #14052
    
    Differential Revision: https://phabricator.haskell.org/D4478
    
    (cherry picked from commit 98c7749cd360293bee96034056e260d70224cef6)


>---------------------------------------------------------------

fbc4ebafb052d0905543ca821801e77b86384db1
 compiler/main/HscTypes.hs                             | 13 +++++++++++--
 testsuite/tests/ghci.debugger/scripts/break011.stdout |  7 -------
 testsuite/tests/ghci.debugger/scripts/hist001.stdout  |  4 ----
 testsuite/tests/ghci.debugger/scripts/hist002.stdout  |  4 ----
 testsuite/tests/ghci/scripts/T11547.script            |  9 ---------
 testsuite/tests/ghci/scripts/T11547.stdout            |  5 -----
 testsuite/tests/ghci/scripts/T2976.stdout             |  2 --
 testsuite/tests/ghci/scripts/all.T                    |  1 -
 8 files changed, 11 insertions(+), 34 deletions(-)

diff --git a/compiler/main/HscTypes.hs b/compiler/main/HscTypes.hs
index fa0eed2..ee0afd4 100644
--- a/compiler/main/HscTypes.hs
+++ b/compiler/main/HscTypes.hs
@@ -1641,7 +1641,7 @@ extendInteractiveContext ictxt new_tythings new_cls_insts new_fam_insts defaults
   = ictxt { ic_mod_index  = ic_mod_index ictxt + 1
                             -- Always bump this; even instances should create
                             -- a new mod_index (Trac #9426)
-          , ic_tythings   = new_tythings ++ ic_tythings ictxt
+          , ic_tythings   = new_tythings ++ old_tythings
           , ic_rn_gbl_env = ic_rn_gbl_env ictxt `icExtendGblRdrEnv` new_tythings
           , ic_instances  = ( new_cls_insts ++ old_cls_insts
                             , new_fam_insts ++ fam_insts )
@@ -1651,6 +1651,8 @@ extendInteractiveContext ictxt new_tythings new_cls_insts new_fam_insts defaults
           , ic_fix_env    = fix_env  -- See Note [Fixity declarations in GHCi]
           }
   where
+    new_ids = [id | AnId id <- new_tythings]
+    old_tythings = filterOut (shadowed_by new_ids) (ic_tythings ictxt)
 
     -- Discard old instances that have been fully overridden
     -- See Note [Override identical instances in GHCi]
@@ -1662,10 +1664,17 @@ extendInteractiveContextWithIds :: InteractiveContext -> [Id] -> InteractiveCont
 extendInteractiveContextWithIds ictxt new_ids
   | null new_ids = ictxt
   | otherwise    = ictxt { ic_mod_index  = ic_mod_index ictxt + 1
-                         , ic_tythings   = new_tythings ++ ic_tythings ictxt
+                         , ic_tythings   = new_tythings ++ old_tythings
                          , ic_rn_gbl_env = ic_rn_gbl_env ictxt `icExtendGblRdrEnv` new_tythings }
   where
     new_tythings = map AnId new_ids
+    old_tythings = filterOut (shadowed_by new_ids) (ic_tythings ictxt)
+
+shadowed_by :: [Id] -> TyThing -> Bool
+shadowed_by ids = shadowed
+  where
+    shadowed id = getOccName id `elemOccSet` new_occs
+    new_occs = mkOccSet (map getOccName ids)
 
 setInteractivePackage :: HscEnv -> HscEnv
 -- Set the 'thisPackage' DynFlag to 'interactive'
diff --git a/testsuite/tests/ghci.debugger/scripts/break011.stdout b/testsuite/tests/ghci.debugger/scripts/break011.stdout
index ac5b7e3..47fb7b1 100644
--- a/testsuite/tests/ghci.debugger/scripts/break011.stdout
+++ b/testsuite/tests/ghci.debugger/scripts/break011.stdout
@@ -23,13 +23,6 @@ _exception = SomeException
                   "foo"
                   "CallStack (from HasCallStack):
   error, called at Test7.hs:2:18 in main:Main")
-Ghci1._exception :: SomeException = SomeException
-                                      (ErrorCallWithLocation
-                                         "foo"
-                                         "CallStack (from HasCallStack):
-  error, called at Test7.hs:<line>:<column> in <package-id>:Main")
-Ghci2._result :: a = _
-Ghci3._result :: IO a = _
 _result :: a = _
 _exception :: SomeException = SomeException
                                 (ErrorCallWithLocation
diff --git a/testsuite/tests/ghci.debugger/scripts/hist001.stdout b/testsuite/tests/ghci.debugger/scripts/hist001.stdout
index 523605b..a19a34f 100644
--- a/testsuite/tests/ghci.debugger/scripts/hist001.stdout
+++ b/testsuite/tests/ghci.debugger/scripts/hist001.stdout
@@ -12,7 +12,6 @@ Logged breakpoint at Test3.hs:2:22-31
 _result :: [a]
 f :: t -> a
 xs :: [t]
-Ghci1._result :: [a] = _
 xs :: [t] = []
 f :: t -> a = _
 _result :: [a] = _
@@ -20,10 +19,7 @@ Logged breakpoint at Test3.hs:2:18-20
 _result :: a
 f :: Integer -> a
 x :: Integer
-Ghci1._result :: [a] = _
 xs :: [t] = []
-Ghci2.f :: t -> a = _
-Ghci2._result :: [a] = _
 x :: Integer = 2
 f :: Integer -> a = _
 _result :: a = _
diff --git a/testsuite/tests/ghci.debugger/scripts/hist002.stdout b/testsuite/tests/ghci.debugger/scripts/hist002.stdout
index 523605b..a19a34f 100644
--- a/testsuite/tests/ghci.debugger/scripts/hist002.stdout
+++ b/testsuite/tests/ghci.debugger/scripts/hist002.stdout
@@ -12,7 +12,6 @@ Logged breakpoint at Test3.hs:2:22-31
 _result :: [a]
 f :: t -> a
 xs :: [t]
-Ghci1._result :: [a] = _
 xs :: [t] = []
 f :: t -> a = _
 _result :: [a] = _
@@ -20,10 +19,7 @@ Logged breakpoint at Test3.hs:2:18-20
 _result :: a
 f :: Integer -> a
 x :: Integer
-Ghci1._result :: [a] = _
 xs :: [t] = []
-Ghci2.f :: t -> a = _
-Ghci2._result :: [a] = _
 x :: Integer = 2
 f :: Integer -> a = _
 _result :: a = _
diff --git a/testsuite/tests/ghci/scripts/T11547.script b/testsuite/tests/ghci/scripts/T11547.script
deleted file mode 100644
index c4c15d6..0000000
--- a/testsuite/tests/ghci/scripts/T11547.script
+++ /dev/null
@@ -1,9 +0,0 @@
-foo = foo
-:t Ghci1.foo
-foo = foo
-:t Ghci2.foo
-:t Ghci1.foo
-data Foo = Foo | Bar
-data Foo = Bar
-:t Foo
-:t Ghci3.Bar
diff --git a/testsuite/tests/ghci/scripts/T11547.stdout b/testsuite/tests/ghci/scripts/T11547.stdout
deleted file mode 100644
index 6f2a833..0000000
--- a/testsuite/tests/ghci/scripts/T11547.stdout
+++ /dev/null
@@ -1,5 +0,0 @@
-Ghci1.foo :: t
-Ghci2.foo :: t
-Ghci1.foo :: t
-Foo :: Ghci3.Foo
-Ghci3.Bar :: Ghci3.Foo
diff --git a/testsuite/tests/ghci/scripts/T2976.stdout b/testsuite/tests/ghci/scripts/T2976.stdout
index de31112..9fdc110 100644
--- a/testsuite/tests/ghci/scripts/T2976.stdout
+++ b/testsuite/tests/ghci/scripts/T2976.stdout
@@ -1,8 +1,6 @@
 test :: Integer = 0
 test = 0
 test :: Integer = 0
-Ghci1.test :: Integer = 0
 test :: [Char] = _
 test = "test"
-Ghci1.test :: Integer = 0
 test :: [Char] = "test"
diff --git a/testsuite/tests/ghci/scripts/all.T b/testsuite/tests/ghci/scripts/all.T
index 016c482..2bcdd0a 100755
--- a/testsuite/tests/ghci/scripts/all.T
+++ b/testsuite/tests/ghci/scripts/all.T
@@ -238,7 +238,6 @@ test('T11376', normal, ghci_script, ['T11376.script'])
 test('T12007', normal, ghci_script, ['T12007.script'])
 test('T11975', normal, ghci_script, ['T11975.script'])
 test('T10963', normal, ghci_script, ['T10963.script'])
-test('T11547', normal, ghci_script, ['T11547.script'])
 test('T11721', normal, ghci_script, ['T11721.script'])
 test('T12520', normal, ghci_script, ['T12520.script'])
 test('T12091', [extra_run_opts('-fobject-code')], ghci_script,


From git at git.haskell.org  Thu Mar 29 16:30:03 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Thu, 29 Mar 2018 16:30:03 +0000 (UTC)
Subject: [commit: ghc] ghc-8.4: Fix tcDataKindSig (02aa02f)
Message-ID: <20180329163003.0F28C3A5F8@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : ghc-8.4
Link       : http://ghc.haskell.org/trac/ghc/changeset/02aa02f1400adcc8a19968886e06e72de621cc78/ghc

>---------------------------------------------------------------

commit 02aa02f1400adcc8a19968886e06e72de621cc78
Author: Simon Peyton Jones <simonpj at microsoft.com>
Date:   Fri Dec 15 09:29:12 2017 +0000

    Fix tcDataKindSig
    
    This patch fixes an outright bug in tcDataKindSig, shown up in Trac
    of a data type declaration.  See Note [TyConBinders for the result kind
    signature of a data type]
    
    I also took the opportunity to elminate the DataKindCheck argument
    and data type from tcDataKindSig, instead moving the check to the
    call site, which is easier to understand.
    
    (cherry picked from commit 68149452a793aedd8d468b689dc93fb2ba5ec436)


>---------------------------------------------------------------

02aa02f1400adcc8a19968886e06e72de621cc78
 compiler/typecheck/TcHsType.hs             | 126 +++++++++++++++++------------
 compiler/typecheck/TcInstDcls.hs           |  20 ++---
 compiler/typecheck/TcTyClsDecls.hs         |  22 +++--
 compiler/types/Type.hs                     |  16 +---
 testsuite/tests/ghci/scripts/T13407.stdout |   2 +-
 testsuite/tests/polykinds/T14515.hs        |  13 +++
 testsuite/tests/polykinds/all.T            |   1 +
 7 files changed, 116 insertions(+), 84 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc 02aa02f1400adcc8a19968886e06e72de621cc78

From git at git.haskell.org  Thu Mar 29 16:30:17 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Thu, 29 Mar 2018 16:30:17 +0000 (UTC)
Subject: [commit: ghc] ghc-8.4: Don't permit data types with return kind
 Constraint (b5c5024)
Message-ID: <20180329163017.6FD8A3A5F8@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : ghc-8.4
Link       : http://ghc.haskell.org/trac/ghc/changeset/b5c5024145668f76ca10610cba7901ed08eb0905/ghc

>---------------------------------------------------------------

commit b5c5024145668f76ca10610cba7901ed08eb0905
Author: Ryan Scott <ryan.gl.scott at gmail.com>
Date:   Mon Mar 19 12:06:41 2018 -0400

    Don't permit data types with return kind Constraint
    
    Previously, GHC allowed all of the following:
    
    ```lang=haskell
    data Foo1 :: Constraint
    data family Foo2 :: Constraint
    data family Foo3 :: k
    data instance Foo3 :: Constraint
    ```
    
    Yikes! This is because GHC was confusing `Type` with `Constraint`
    due to careless use of the `isLiftedTypeKind` function. To respect
    this distinction, I swapped `isLiftedTypeKind` out for
    `tcIsStarKind`—which does respect this distinction—in the right
    places.
    
    Test Plan: make test TEST="T14048a T14048b T14048c"
    
    Reviewers: bgamari
    
    Reviewed By: bgamari
    
    Subscribers: goldfire, rwbarton, thomie, carter
    
    GHC Trac Issues: #14048
    
    Differential Revision: https://phabricator.haskell.org/D4479
    
    (cherry picked from commit f748c52997f61a9f58eccbf4b8df0a0c8c6887e5)


>---------------------------------------------------------------

b5c5024145668f76ca10610cba7901ed08eb0905
 compiler/typecheck/TcInstDcls.hs                     | 5 +++--
 compiler/typecheck/TcTyClsDecls.hs                   | 4 ++--
 testsuite/tests/typecheck/should_fail/T14048a.hs     | 6 ++++++
 testsuite/tests/typecheck/should_fail/T14048a.stderr | 5 +++++
 testsuite/tests/typecheck/should_fail/T14048b.hs     | 7 +++++++
 testsuite/tests/typecheck/should_fail/T14048b.stderr | 6 ++++++
 testsuite/tests/typecheck/should_fail/T14048c.hs     | 9 +++++++++
 testsuite/tests/typecheck/should_fail/T14048c.stderr | 5 +++++
 testsuite/tests/typecheck/should_fail/all.T          | 3 +++
 9 files changed, 46 insertions(+), 4 deletions(-)

diff --git a/compiler/typecheck/TcInstDcls.hs b/compiler/typecheck/TcInstDcls.hs
index 99a6ff3..7e9f93d 100644
--- a/compiler/typecheck/TcInstDcls.hs
+++ b/compiler/typecheck/TcInstDcls.hs
@@ -41,6 +41,7 @@ import TcUnify
 import CoreSyn    ( Expr(..), mkApps, mkVarApps, mkLams )
 import MkCore     ( nO_METHOD_BINDING_ERROR_ID )
 import CoreUnfold ( mkInlineUnfoldingWithArity, mkDFunUnfolding )
+import Kind
 import Type
 import TcEvidence
 import TyCon
@@ -680,7 +681,7 @@ tcDataFamInstDecl mb_clsinfo
          -- Deal with any kind signature.
          -- See also Note [Arity of data families] in FamInstEnv
        ; (extra_tcbs, final_res_kind) <- tcDataKindSig full_tcbs res_kind'
-       ; checkTc (isLiftedTypeKind final_res_kind) (badKindSig True res_kind')
+       ; checkTc (tcIsStarKind final_res_kind) (badKindSig True res_kind')
 
        ; let extra_pats  = map (mkTyVarTy . binderVar) extra_tcbs
              all_pats    = pats' `chkAppend` extra_pats
@@ -722,7 +723,7 @@ tcDataFamInstDecl mb_clsinfo
        ; checkValidFamPats mb_clsinfo fam_tc tvs' [] pats' extra_pats pp_hs_pats
 
          -- Result kind must be '*' (otherwise, we have too few patterns)
-       ; checkTc (isLiftedTypeKind final_res_kind) $
+       ; checkTc (tcIsStarKind final_res_kind) $
          tooFewParmsErr (tyConArity fam_tc)
 
        ; checkValidTyCon rep_tc
diff --git a/compiler/typecheck/TcTyClsDecls.hs b/compiler/typecheck/TcTyClsDecls.hs
index 9261905..89ec295 100644
--- a/compiler/typecheck/TcTyClsDecls.hs
+++ b/compiler/typecheck/TcTyClsDecls.hs
@@ -882,7 +882,7 @@ tcFamDecl1 parent (FamilyDecl { fdInfo = fam_info, fdLName = tc_lname@(L _ tc_na
   -- Data families might have a variable return kind.
   -- See See Note [Arity of data families] in FamInstEnv.
   ; (extra_binders, final_res_kind) <- tcDataKindSig binders res_kind
-  ; checkTc (isLiftedTypeKind final_res_kind
+  ; checkTc (tcIsStarKind final_res_kind
              || isJust (tcGetCastedTyVar_maybe final_res_kind))
             (badKindSig False res_kind)
 
@@ -1034,7 +1034,7 @@ tcDataDefn roles_info
        ; let hsc_src = tcg_src tcg_env
        ; (extra_bndrs, final_res_kind) <- tcDataKindSig tycon_binders res_kind
        ; unless (mk_permissive_kind hsc_src cons) $
-         checkTc (isLiftedTypeKind final_res_kind) (badKindSig True res_kind)
+         checkTc (tcIsStarKind final_res_kind) (badKindSig True res_kind)
 
        ; let final_bndrs  = tycon_binders `chkAppend` extra_bndrs
              roles        = roles_info tc_name
diff --git a/testsuite/tests/typecheck/should_fail/T14048a.hs b/testsuite/tests/typecheck/should_fail/T14048a.hs
new file mode 100644
index 0000000..c717127
--- /dev/null
+++ b/testsuite/tests/typecheck/should_fail/T14048a.hs
@@ -0,0 +1,6 @@
+{-# LANGUAGE ConstraintKinds #-}
+module T14048a where
+
+import Data.Kind
+
+data Foo :: Constraint
diff --git a/testsuite/tests/typecheck/should_fail/T14048a.stderr b/testsuite/tests/typecheck/should_fail/T14048a.stderr
new file mode 100644
index 0000000..48a91c7
--- /dev/null
+++ b/testsuite/tests/typecheck/should_fail/T14048a.stderr
@@ -0,0 +1,5 @@
+
+T14048a.hs:6:1: error:
+    • Kind signature on data type declaration has non-* return kind
+        Constraint
+    • In the data declaration for ‘Foo’
diff --git a/testsuite/tests/typecheck/should_fail/T14048b.hs b/testsuite/tests/typecheck/should_fail/T14048b.hs
new file mode 100644
index 0000000..d2f6f74
--- /dev/null
+++ b/testsuite/tests/typecheck/should_fail/T14048b.hs
@@ -0,0 +1,7 @@
+{-# LANGUAGE ConstraintKinds #-}
+{-# LANGUAGE TypeFamilies #-}
+module T14048b where
+
+import Data.Kind
+
+data family Foo :: Constraint
diff --git a/testsuite/tests/typecheck/should_fail/T14048b.stderr b/testsuite/tests/typecheck/should_fail/T14048b.stderr
new file mode 100644
index 0000000..fe78d9f
--- /dev/null
+++ b/testsuite/tests/typecheck/should_fail/T14048b.stderr
@@ -0,0 +1,6 @@
+
+T14048b.hs:7:1: error:
+    • Kind signature on data type declaration has non-*
+      and non-variable return kind
+        Constraint
+    • In the data family declaration for ‘Foo’
diff --git a/testsuite/tests/typecheck/should_fail/T14048c.hs b/testsuite/tests/typecheck/should_fail/T14048c.hs
new file mode 100644
index 0000000..e81e454
--- /dev/null
+++ b/testsuite/tests/typecheck/should_fail/T14048c.hs
@@ -0,0 +1,9 @@
+{-# LANGUAGE ConstraintKinds #-}
+{-# LANGUAGE PolyKinds #-}
+{-# LANGUAGE TypeFamilies #-}
+module T14048c where
+
+import Data.Kind
+
+data family   Foo :: k
+data instance Foo :: Constraint
diff --git a/testsuite/tests/typecheck/should_fail/T14048c.stderr b/testsuite/tests/typecheck/should_fail/T14048c.stderr
new file mode 100644
index 0000000..7e83d19
--- /dev/null
+++ b/testsuite/tests/typecheck/should_fail/T14048c.stderr
@@ -0,0 +1,5 @@
+
+T14048c.hs:9:1: error:
+    • Kind signature on data type declaration has non-* return kind
+        Constraint
+    • In the data instance declaration for ‘Foo’
diff --git a/testsuite/tests/typecheck/should_fail/all.T b/testsuite/tests/typecheck/should_fail/all.T
index b1a0e75..734561f 100644
--- a/testsuite/tests/typecheck/should_fail/all.T
+++ b/testsuite/tests/typecheck/should_fail/all.T
@@ -457,6 +457,9 @@ test('T14000', normal, compile_fail, [''])
 test('T14055', normal, compile_fail, [''])
 test('T13909', normal, compile_fail, [''])
 test('T13929', normal, compile_fail, [''])
+test('T14048a', normal, compile_fail, [''])
+test('T14048b', normal, compile_fail, [''])
+test('T14048c', normal, compile_fail, [''])
 test('T14232', normal, compile_fail, [''])
 test('T14325', normal, compile_fail, [''])
 test('T14350', normal, compile_fail, [''])


From git at git.haskell.org  Thu Mar 29 17:45:20 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Thu, 29 Mar 2018 17:45:20 +0000 (UTC)
Subject: [commit: ghc] master: Fix syntax in -flate-specialise docs (0017a7b)
Message-ID: <20180329174520.024E83A5F8@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/0017a7b618353bf984d701f6d8ee2810a425e5b3/ghc

>---------------------------------------------------------------

commit 0017a7b618353bf984d701f6d8ee2810a425e5b3
Author: Simon Jakobi <simon.jakobi at gmail.com>
Date:   Thu Mar 29 13:35:40 2018 +0200

    Fix syntax in -flate-specialise docs


>---------------------------------------------------------------

0017a7b618353bf984d701f6d8ee2810a425e5b3
 docs/users_guide/using-optimisation.rst | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/docs/users_guide/using-optimisation.rst b/docs/users_guide/using-optimisation.rst
index d6c24de..8466406 100644
--- a/docs/users_guide/using-optimisation.rst
+++ b/docs/users_guide/using-optimisation.rst
@@ -888,6 +888,8 @@ by saying ``-fno-wombat``.
     :shortdesc: Run a late specialisation pass
     :type: dynamic
     :reverse: -fno-late-specialise
+    :category:
+
     :default: off
 
     Runs another specialisation pass towards the end of the optimisation


From git at git.haskell.org  Fri Mar 30 11:10:49 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Fri, 30 Mar 2018 11:10:49 +0000 (UTC)
Subject: [commit: ghc] wip/tdammers/D4394: Fix rebasing-induced failures
 (af9a1e9)
Message-ID: <20180330111049.111FC3A5F8@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : wip/tdammers/D4394
Link       : http://ghc.haskell.org/trac/ghc/changeset/af9a1e9dc0390340af16ddc1d9ee0aaa1f94295c/ghc

>---------------------------------------------------------------

commit af9a1e9dc0390340af16ddc1d9ee0aaa1f94295c
Author: Tobias Dammers <tdammers at gmail.com>
Date:   Fri Mar 30 13:09:59 2018 +0200

    Fix rebasing-induced failures


>---------------------------------------------------------------

af9a1e9dc0390340af16ddc1d9ee0aaa1f94295c
 compiler/typecheck/TcType.hs |  2 +-
 compiler/types/Coercion.hs   |  4 ++--
 compiler/types/Type.hs       | 12 +++++++++++-
 3 files changed, 14 insertions(+), 4 deletions(-)

diff --git a/compiler/typecheck/TcType.hs b/compiler/typecheck/TcType.hs
index c1cb52c..9758d03 100644
--- a/compiler/typecheck/TcType.hs
+++ b/compiler/typecheck/TcType.hs
@@ -68,7 +68,7 @@ module TcType (
   tcTyConAppTyCon, tcTyConAppTyCon_maybe, tcTyConAppArgs,
   tcSplitAppTy_maybe, tcSplitAppTy, tcSplitAppTys, tcRepSplitAppTy_maybe,
   tcRepGetNumAppTys,
-  tcGetCastedTyVar_maybe, tcGetTyVar_maybe, tcGetTyVar,
+  tcGetCastedTyVar_maybe, tcGetTyVar_maybe, tcGetTyVar, nextRole,
   tcSplitSigmaTy, tcSplitNestedSigmaTys, tcDeepSplitSigmaTy_maybe,
 
   ---------------------------------
diff --git a/compiler/types/Coercion.hs b/compiler/types/Coercion.hs
index 6e6f07c..2807512 100644
--- a/compiler/types/Coercion.hs
+++ b/compiler/types/Coercion.hs
@@ -278,7 +278,7 @@ decomposePiCos orig_kind orig_args orig_co = go [] orig_subst orig_kind orig_arg
         --          ty :: s2
         -- need arg_co :: s2 ~ s1
         --      res_co :: t1[ty |> arg_co / a] ~ t2[ty / b]
-      = let arg_co = mkNthCo 0 (mkSymCo co)
+      = let arg_co = mkNthCo Nominal 0 (mkSymCo co)
             res_co = mkInstCo co (mkNomReflCo ty `mkCoherenceLeftCo` arg_co)
             subst' = extendTCvSubst subst kv ty
         in
@@ -290,7 +290,7 @@ decomposePiCos orig_kind orig_args orig_co = go [] orig_subst orig_kind orig_arg
         --          ty :: s2
         -- need arg_co :: s2 ~ s1
         --      res_co :: t1 ~ t2
-      = let (sym_arg_co, res_co) = decomposeFunCo co
+      = let (sym_arg_co, res_co) = decomposeFunCo Representational co
             arg_co               = mkSymCo sym_arg_co
         in
         go (arg_co : acc_arg_cos) subst res_ki tys res_co
diff --git a/compiler/types/Type.hs b/compiler/types/Type.hs
index 0ddfe09..e599012 100644
--- a/compiler/types/Type.hs
+++ b/compiler/types/Type.hs
@@ -30,7 +30,7 @@ module Type (
         mkTyConApp, mkTyConTy,
         tyConAppTyCon_maybe, tyConAppTyConPicky_maybe,
         tyConAppArgs_maybe, tyConAppTyCon, tyConAppArgs,
-        splitTyConApp_maybe, splitTyConApp, tyConAppArgN,
+        splitTyConApp_maybe, splitTyConApp, tyConAppArgN, nextRole,
         tcRepSplitTyConApp_maybe, tcSplitTyConApp_maybe,
         splitListTyConApp_maybe,
         repSplitTyConApp_maybe,
@@ -1140,6 +1140,16 @@ splitListTyConApp_maybe ty = case splitTyConApp_maybe ty of
   Just (tc,[e]) | tc == listTyCon -> Just e
   _other                          -> Nothing
 
+nextRole :: Type -> Role
+nextRole ty
+  | Just (tc, tys) <- splitTyConApp_maybe ty
+  , let num_tys = length tys
+  , num_tys < tyConArity tc
+  = tyConRoles tc `getNth` num_tys
+
+  | otherwise
+  = Nominal
+
 newTyConInstRhs :: TyCon -> [Type] -> Type
 -- ^ Unwrap one 'layer' of newtype on a type constructor and its
 -- arguments, using an eta-reduced version of the @newtype@ if possible.


From git at git.haskell.org  Fri Mar 30 12:00:03 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Fri, 30 Mar 2018 12:00:03 +0000 (UTC)
Subject: [commit: ghc] master: Update a few comments regarding CAF lists
 (c00b6d2)
Message-ID: <20180330120003.585E03A5F8@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/c00b6d200c5c0c37c2936f12f27c5ebc3716a76f/ghc

>---------------------------------------------------------------

commit c00b6d200c5c0c37c2936f12f27c5ebc3716a76f
Author: Ömer Sinan Ağacan <omeragacan at gmail.com>
Date:   Fri Mar 30 14:58:57 2018 +0300

    Update a few comments regarding CAF lists
    
    [skip ci]


>---------------------------------------------------------------

c00b6d200c5c0c37c2936f12f27c5ebc3716a76f
 includes/rts/storage/Closures.h |  4 +++-
 rts/sm/GC.c                     |  4 ++--
 rts/sm/Storage.c                | 10 +++++-----
 3 files changed, 10 insertions(+), 8 deletions(-)

diff --git a/includes/rts/storage/Closures.h b/includes/rts/storage/Closures.h
index af89507..e5b274d 100644
--- a/includes/rts/storage/Closures.h
+++ b/includes/rts/storage/Closures.h
@@ -122,8 +122,10 @@ typedef struct {
 typedef struct {
     StgHeader     header;
     StgClosure   *indirectee;
-    StgClosure   *static_link;
+    StgClosure   *static_link; // See Note [CAF lists]
     const StgInfoTable *saved_info;
+        // `saved_info` also used for the link field for `debug_caf_list`,
+        // see `newCAF` and Note [CAF lists]
 } StgIndStatic;
 
 typedef struct StgBlockingQueue_ {
diff --git a/rts/sm/GC.c b/rts/sm/GC.c
index d7d3723..9e6bd55 100644
--- a/rts/sm/GC.c
+++ b/rts/sm/GC.c
@@ -1831,8 +1831,8 @@ resize_nursery (void)
    Sanity code for CAF garbage collection.
 
    With DEBUG turned on, we manage a CAF list in addition to the SRT
-   mechanism.  After GC, we run down the CAF list and blackhole any
-   CAFs which have been garbage collected.  This means we get an error
+   mechanism.  After GC, we run down the CAF list and make any
+   CAFs which have been garbage collected GCD_CAF.  This means we get an error
    whenever the program tries to enter a garbage collected CAF.
 
    Any garbage collected CAFs are taken off the CAF list at the same
diff --git a/rts/sm/Storage.c b/rts/sm/Storage.c
index c4dbdc2..9174646 100644
--- a/rts/sm/Storage.c
+++ b/rts/sm/Storage.c
@@ -303,10 +303,10 @@ freeStorage (bool free_heap)
 
    The entry code for every CAF does the following:
 
-      - calls newCaf, which builds a CAF_BLACKHOLE on the heap and atomically
+      - calls newCAF, which builds a CAF_BLACKHOLE on the heap and atomically
         updates the CAF with IND_STATIC pointing to the CAF_BLACKHOLE
 
-      - if newCaf returns zero, it re-enters the CAF (see Note [atomic
+      - if newCAF returns zero, it re-enters the CAF (see Note [atomic
         CAF entry])
 
       - pushes an update frame pointing to the CAF_BLACKHOLE
@@ -317,7 +317,7 @@ freeStorage (bool free_heap)
    too, and various other parts of the RTS that deal with update
    frames would also need special cases for static update frames.
 
-   newCaf() does the following:
+   newCAF() does the following:
 
       - atomically locks the CAF (see [atomic CAF entry])
 
@@ -335,7 +335,7 @@ freeStorage (bool free_heap)
    ------------------
    Note [atomic CAF entry]
 
-   With THREADED_RTS, newCaf() is required to be atomic (see
+   With THREADED_RTS, newCAF() is required to be atomic (see
    #5558). This is because if two threads happened to enter the same
    CAF simultaneously, they would create two distinct CAF_BLACKHOLEs,
    and so the normal threadPaused() machinery for detecting duplicate
@@ -355,7 +355,7 @@ freeStorage (bool free_heap)
       - we must be able to *revert* CAFs that have been evaluated, to
         their pre-evaluated form.
 
-      To do this, we use an additional CAF list.  When newCaf() is
+      To do this, we use an additional CAF list.  When newCAF() is
       called on a dynamically-loaded CAF, we add it to the CAF list
       instead of the old-generation mutable list, and save away its
       old info pointer (in caf->saved_info) for later reversion.


From git at git.haskell.org  Sat Mar 31 08:04:22 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Sat, 31 Mar 2018 08:04:22 +0000 (UTC)
Subject: [commit: ghc] master: printClosure: slightly improve MVAR printing
 (afb686a)
Message-ID: <20180331080422.A7B663A5F8@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/afb686a88901d7d0c93627806d7e4d0444aa17e8/ghc

>---------------------------------------------------------------

commit afb686a88901d7d0c93627806d7e4d0444aa17e8
Author: Ömer Sinan Ağacan <omeragacan at gmail.com>
Date:   Sat Mar 31 11:03:44 2018 +0300

    printClosure: slightly improve MVAR printing
    
    Reviewers: bgamari, erikd, simonmar
    
    Reviewed By: bgamari
    
    Subscribers: thomie, carter
    
    Differential Revision: https://phabricator.haskell.org/D4541


>---------------------------------------------------------------

afb686a88901d7d0c93627806d7e4d0444aa17e8
 rts/Printer.c | 26 ++++++++++++++++++++++++--
 1 file changed, 24 insertions(+), 2 deletions(-)

diff --git a/rts/Printer.c b/rts/Printer.c
index 904f23a..1c9634d 100644
--- a/rts/Printer.c
+++ b/rts/Printer.c
@@ -331,7 +331,29 @@ printClosure( const StgClosure *obj )
     case MVAR_DIRTY:
         {
           StgMVar* mv = (StgMVar*)obj;
-          debugBelch("MVAR(head=%p, tail=%p, value=%p)\n", mv->head, mv->tail, mv->value);
+
+          debugBelch("MVAR(head=");
+          if ((StgClosure*)mv->head == &stg_END_TSO_QUEUE_closure) {
+              debugBelch("END_TSO_QUEUE");
+          } else {
+              debugBelch("%p", mv->head);
+          }
+
+          debugBelch(", tail=");
+          if ((StgClosure*)mv->tail == &stg_END_TSO_QUEUE_closure) {
+              debugBelch("END_TSO_QUEUE");
+          } else {
+              debugBelch("%p", mv->tail);
+          }
+
+          debugBelch(", value=");
+          if ((StgClosure*)mv->value == &stg_END_TSO_QUEUE_closure) {
+              debugBelch("END_TSO_QUEUE");
+          } else {
+              debugBelch("%p", mv->value);
+          }
+          debugBelch(")\n");
+
           break;
         }
 
@@ -358,7 +380,7 @@ printClosure( const StgClosure *obj )
 
     case WEAK:
             debugBelch("WEAK(");
-            debugBelch(" key=%p value=%p finalizer=%p",
+            debugBelch("key=%p value=%p finalizer=%p",
                     (StgPtr)(((StgWeak*)obj)->key),
                     (StgPtr)(((StgWeak*)obj)->value),
                     (StgPtr)(((StgWeak*)obj)->finalizer));


From git at git.haskell.org  Sat Mar 31 09:12:14 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Sat, 31 Mar 2018 09:12:14 +0000 (UTC)
Subject: [commit: ghc] master: Remove MAX_PATH restrictions from RTS,
 I/O manager and various utilities (4de585a)
Message-ID: <20180331091214.7B2823A5F8@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/4de585a5c1ac3edc2914cebcac1753b514051a89/ghc

>---------------------------------------------------------------

commit 4de585a5c1ac3edc2914cebcac1753b514051a89
Author: Tamar Christina <tamar at zhox.com>
Date:   Thu Mar 29 14:22:09 2018 +0100

    Remove MAX_PATH restrictions from RTS, I/O manager and various utilities
    
    Summary:
    This shims out fopen and sopen so that they use modern APIs under the hood
    along with namespaced paths.
    
    This lifts the MAX_PATH restrictions from Haskell programs and makes the new
    limit ~32k.
    
    There are only some slight caveats that have been documented.
    
    Some utilities have not been upgraded such as lndir, since all these things are
    different cabal packages I have been forced to copy the source in different places
    which is less than ideal. But it's the only way to keep sdist working.
    
    Test Plan: ./validate
    
    Reviewers: hvr, bgamari, erikd, simonmar
    
    Reviewed By: bgamari
    
    Subscribers: rwbarton, thomie, carter
    
    GHC Trac Issues: #10822
    
    Differential Revision: https://phabricator.haskell.org/D4416


>---------------------------------------------------------------

4de585a5c1ac3edc2914cebcac1753b514051a89
 .gitignore                       |   5 +
 configure.ac                     |   9 ++
 docs/users_guide/8.6.1-notes.rst |  48 ++++++-
 ghc.mk                           |  10 ++
 libraries/base/base.cabal        |   2 +
 libraries/base/include/HsBase.h  |  16 ++-
 rts/Hpc.c                        |   5 +-
 rts/Linker.c                     |   3 +-
 rts/PathUtils.h                  |   2 +-
 rts/ProfHeap.c                   |   3 +-
 rts/Profiling.c                  |   5 +-
 rts/RtsFlags.c                   |   6 +-
 rts/RtsSymbols.c                 |   1 +
 rts/eventlog/EventLogWriter.c    |   3 +-
 rts/fs_rts.h                     |  15 ++
 rts/ghc.mk                       |   2 +-
 rts/linker/LoadArchive.c         |   1 +
 rts/linker/PEi386.c              |   3 +
 rts/rts.cabal.in                 |   3 +
 utils/fs/README                  |   4 +
 utils/fs/fs.c                    | 293 +++++++++++++++++++++++++++++++++++++++
 utils/fs/fs.h                    |  36 +++++
 utils/lndir/lndir.c              |   5 +-
 utils/unlit/ghc.mk               |   2 +-
 utils/unlit/unlit.c              |   5 +-
 utils/unlit/unlit.cabal          |   3 +-
 26 files changed, 469 insertions(+), 21 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc 4de585a5c1ac3edc2914cebcac1753b514051a89

From git at git.haskell.org  Sat Mar 31 10:55:09 2018
From: git at git.haskell.org (git at git.haskell.org)
Date: Sat, 31 Mar 2018 10:55:09 +0000 (UTC)
Subject: [commit: ghc] master: testsuite: allow accepting of fine grained
 results [skip ci] (ca535f9)
Message-ID: <20180331105509.050243A5F8@ghc.haskell.org>

Repository : ssh://git at git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/ca535f95a742d885c4082c9dc296c151fb3c1e12/ghc

>---------------------------------------------------------------

commit ca535f95a742d885c4082c9dc296c151fb3c1e12
Author: Tamar Christina <tamar at zhox.com>
Date:   Sat Mar 31 11:14:17 2018 +0100

    testsuite: allow accepting of fine grained results [skip ci]
    
    Summary:
    Sometimes we need to be able to mass accept changes that are platform
    specific and that can't be normalized away using our string formatters.
    
    e.g. differences in I/O manager errors or behaviors. This allows one
    to do so easier than before and less error prone.
    
    I have updated the docs and made it clear this should only be used
    when a normalizer won't work:
    
    https://ghc.haskell.org/trac/ghc/wiki/Building/RunningTests/Updating
    
    Test Plan: Manually tested while working on new I/O manager
    
    Reviewers: bgamari
    
    Subscribers: thomie, carter
    
    Differential Revision: https://phabricator.haskell.org/D4549


>---------------------------------------------------------------

ca535f95a742d885c4082c9dc296c151fb3c1e12
 testsuite/driver/testglobals.py |  2 ++
 testsuite/driver/testlib.py     | 14 ++++++++++++--
 testsuite/mk/test.mk            | 12 ++++++++++++
 3 files changed, 26 insertions(+), 2 deletions(-)

diff --git a/testsuite/driver/testglobals.py b/testsuite/driver/testglobals.py
index 44fe125..f6831c9 100644
--- a/testsuite/driver/testglobals.py
+++ b/testsuite/driver/testglobals.py
@@ -28,6 +28,8 @@ class TestConfig:
 
         # Accept new output which differs from the sample?
         self.accept = 0
+        self.accept_platform = 0
+        self.accept_os = 0
 
         # File in which to save the summary
         self.summary_file = ''
diff --git a/testsuite/driver/testlib.py b/testsuite/driver/testlib.py
index 8bdbedf..f2bb1c9 100644
--- a/testsuite/driver/testlib.py
+++ b/testsuite/driver/testlib.py
@@ -1597,7 +1597,17 @@ def compare_outputs(way, kind, normaliser, expected_file, actual_file,
             if_verbose(1, 'Test is expected to fail. Not accepting new output.')
             return 0
         elif config.accept and actual_raw:
-            if_verbose(1, 'Accepting new output.')
+            if config.accept_platform:
+                if_verbose(1, 'Accepting new output for platform "'
+                              + config.platform + '".')
+                expected_path += '-' + config.platform
+            elif config.accept_os:
+                if_verbose(1, 'Accepting new output for os "'
+                              + config.os + '".')
+                expected_path += '-' + config.os
+            else:
+                if_verbose(1, 'Accepting new output.')
+
             write_file(expected_path, actual_raw)
             return 1
         elif config.accept:
@@ -1914,7 +1924,7 @@ def in_srcdir(name, suffix=''):
 
 # Finding the sample output.  The filename is of the form
 #
-#   <test>.stdout[-ws-<wordsize>][-<platform>]
+#   <test>.stdout[-ws-<wordsize>][-<platform>|-<os>]
 #
 def find_expected_file(name, suff):
     basename = add_suffix(name, suff)
diff --git a/testsuite/mk/test.mk b/testsuite/mk/test.mk
index a21c4bb..1eb8d49 100644
--- a/testsuite/mk/test.mk
+++ b/testsuite/mk/test.mk
@@ -14,6 +14,9 @@
 #  CONFIG    -- use a different configuration file
 #  COMPILER  -- select a configuration file from config/
 #  THREADS   -- run n tests at once
+#  PLATFORM  -- if accepting a result, accept it for the current platform.
+#  OS        -- if accepting a result, accept it for all wordsizes of the
+#               current os.
 #
 # -----------------------------------------------------------------------------
 
@@ -280,6 +283,15 @@ endif
 
 ifeq "$(accept)" "YES"
 setaccept = -e config.accept=1
+
+ifeq "$(PLATFORM)" "YES"
+setaccept += -e config.accept_platform=1
+endif
+
+ifeq "$(OS)" "YES"
+setaccept += -e config.accept_os=1
+endif
+
 else
 setaccept =
 endif