[commit: ghc] master: Fix Template Haskell reification of unboxed tuple types (514c4a4)

[git at git.haskell.org]

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

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/514c4a4741f3881672f1ccc1fe6d08a5d596bb87/ghc

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

commit 514c4a4741f3881672f1ccc1fe6d08a5d596bb87
Author: Ryan Scott <ryan.gl.scott at gmail.com>
Date:   Mon Jul 18 09:29:05 2016 -0400

    Fix Template Haskell reification of unboxed tuple types
    
    Summary:
    Previously, Template Haskell reified unboxed tuple types as boxed
    tuples with twice the appropriate arity.
    
    Fixes #12403.
    
    Test Plan: make test TEST=T12403
    
    Reviewers: hvr, goldfire, austin, bgamari
    
    Reviewed By: goldfire
    
    Subscribers: thomie
    
    Differential Revision: https://phabricator.haskell.org/D2405
    
    GHC Trac Issues: #12403


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

514c4a4741f3881672f1ccc1fe6d08a5d596bb87
 compiler/typecheck/TcSplice.hs                        | 4 +++-
 docs/users_guide/8.0.2-notes.rst                      | 6 ++++++
 testsuite/tests/th/{T10697_decided_1.hs => T12403.hs} | 5 +++--
 testsuite/tests/th/T12403.stdout                      | 1 +
 testsuite/tests/th/all.T                              | 2 ++
 5 files changed, 15 insertions(+), 3 deletions(-)

diff --git a/compiler/typecheck/TcSplice.hs b/compiler/typecheck/TcSplice.hs
index fa68d2e..6ae1ba4 100644
--- a/compiler/typecheck/TcSplice.hs
+++ b/compiler/typecheck/TcSplice.hs
@@ -1819,7 +1819,9 @@ reify_tc_app tc tys
     tc_binders  = tyConBinders tc
     tc_res_kind = tyConResKind tc
 
-    r_tc | isTupleTyCon tc                = if isPromotedDataCon tc
+    r_tc | isUnboxedTupleTyCon tc         = TH.UnboxedTupleT (arity `div` 2)
+             -- See Note [Unboxed tuple RuntimeRep vars] in TyCon
+         | isTupleTyCon tc                = if isPromotedDataCon tc
                                             then TH.PromotedTupleT arity
                                             else TH.TupleT arity
          | tc `hasKey` listTyConKey       = TH.ListT
diff --git a/docs/users_guide/8.0.2-notes.rst b/docs/users_guide/8.0.2-notes.rst
index d5d442f..39ad028 100644
--- a/docs/users_guide/8.0.2-notes.rst
+++ b/docs/users_guide/8.0.2-notes.rst
@@ -32,6 +32,12 @@ Compiler
    initial cmm from STG-to-C-- code generation and :ghc-flag:`-ddump-cmm-verbose`
    to obtain the intermediates from all C-- pipeline stages.
 
+Template Haskell
+~~~~~~~~~~~~~~~~
+
+-  Reifying types that contain unboxed tuples now works correctly. (Previously,
+   Template Haskell reified unboxed tuples as boxed tuples with twice their
+   appropriate arity.)
 
 TODO FIXME Heading title
 ~~~~~~~~~~~~~~~~~~~~~~~~
diff --git a/testsuite/tests/th/T10697_decided_1.hs b/testsuite/tests/th/T12403.hs
similarity index 50%
copy from testsuite/tests/th/T10697_decided_1.hs
copy to testsuite/tests/th/T12403.hs
index 241cec3..d4aad62 100644
--- a/testsuite/tests/th/T10697_decided_1.hs
+++ b/testsuite/tests/th/T12403.hs
@@ -1,11 +1,12 @@
 {-# LANGUAGE TemplateHaskell #-}
+{-# LANGUAGE UnboxedTuples #-}
 module Main where
 
 import Language.Haskell.TH
 
-data T = T {-# UNPACK #-} !Int !Int Int
+data T = T (# Int, Int #)
 
 $(return [])
 
 main :: IO ()
-main = putStrLn $(reifyConStrictness 'T >>= stringE . show)
+main = putStrLn $(reify ''T >>= stringE . pprint)
diff --git a/testsuite/tests/th/T12403.stdout b/testsuite/tests/th/T12403.stdout
new file mode 100644
index 0000000..9b75e8b
--- /dev/null
+++ b/testsuite/tests/th/T12403.stdout
@@ -0,0 +1 @@
+data Main.T = Main.T ((# , #) GHC.Types.Int GHC.Types.Int)
diff --git a/testsuite/tests/th/all.T b/testsuite/tests/th/all.T
index ff2d6d4..3f448d7 100644
--- a/testsuite/tests/th/all.T
+++ b/testsuite/tests/th/all.T
@@ -418,3 +418,5 @@ test('T11484', normal, compile, ['-v0'])
 test('T8761', normal, compile, ['-v0 -ddump-splices -dsuppress-uniques'])
 test('T12130', extra_clean(['T12130a.hi','T12130a.o']),
               multimod_compile, ['T12130', '-v0 ' + config.ghc_th_way_flags])
+test('T12403', omit_ways(['ghci']),
+              compile_and_run, ['-v0 -ddump-splices -dsuppress-uniques'])