[commit: ghc] master: Build system: renable -Wall on validate (base) (987d542)

[git at git.haskell.org]

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

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/987d542749be3b53d8461fa5abb770f0b9d8ba5e/ghc

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

commit 987d542749be3b53d8461fa5abb770f0b9d8ba5e
Author: Thomas Miedema <thomasmiedema at gmail.com>
Date:   Tue Nov 3 16:17:35 2015 -0600

    Build system: renable -Wall on validate (base)
    
    Problem: 'SRC_HC_OPTS += -Wall' in 'mk/warnings.mk' was getting
    overwritten by 'SRC_HC_OPTS = ...' in 'mk/flavours/*.mk'.
    
    It didn't affect the compiler or most other libraries, because most
    .cabal files define 'ghc-options: -Wall'.
    
    Bug introduced in commit
    2c24fd707f8650205bb574ffac5f376239af3723, when moving validate settings
    from 'mk/validate-settings.mk' to 'mk/flavours/validate.mk'.
    
    Reviewed By: austin
    
    Differential Revision: https://phabricator.haskell.org/D1425


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

987d542749be3b53d8461fa5abb770f0b9d8ba5e
 ghc.mk                           | 8 ++++++++
 libraries/base/Data/Semigroup.hs | 1 -
 libraries/base/GHC/Enum.hs       | 2 +-
 libraries/base/GHC/GHCi.hs       | 2 +-
 mk/warnings.mk                   | 3 ---
 5 files changed, 10 insertions(+), 6 deletions(-)

diff --git a/ghc.mk b/ghc.mk
index 07e1edc..aaf7d00 100644
--- a/ghc.mk
+++ b/ghc.mk
@@ -142,6 +142,14 @@ include mk/warnings.mk
 
 # (Optional) build-specific configuration
 include mk/custom-settings.mk
+SRC_CC_OPTS     += -Wall
+SRC_HC_OPTS     += -Wall
+# Don't add -Werror to GhcStage1HcOpts, because otherwise validate may
+# unnecessarily fail during the stage1 build when booting with an older
+# compiler.
+# It would be better to only exclude certain warnings from becoming errors
+# (e.g. '-Werror -Wno-error=unused-imports -Wno-error=...'), but -Wno-error
+# isn't supported yet (https://ghc.haskell.org/trac/ghc/wiki/Design/Warnings).
 SRC_CC_OPTS     += $(WERROR)
 GhcStage2HcOpts += $(WERROR)
 GhcLibHcOpts    += $(WERROR)
diff --git a/libraries/base/Data/Semigroup.hs b/libraries/base/Data/Semigroup.hs
index 6c92df9..0cd556d 100644
--- a/libraries/base/Data/Semigroup.hs
+++ b/libraries/base/Data/Semigroup.hs
@@ -78,7 +78,6 @@ import           Data.Monoid         (All (..), Any (..), Dual (..), Endo (..),
                                       Product (..), Sum (..))
 import           Data.Monoid         (Alt (..))
 import qualified Data.Monoid         as Monoid
-import           Data.Proxy
 import           Data.Void
 import           GHC.Generics
 
diff --git a/libraries/base/GHC/Enum.hs b/libraries/base/GHC/Enum.hs
index 0d91cc7..dcda47b 100644
--- a/libraries/base/GHC/Enum.hs
+++ b/libraries/base/GHC/Enum.hs
@@ -704,7 +704,7 @@ the special case varies more from the general case, due to the issue of overflow
 
 {-# NOINLINE [0] enumDeltaIntegerFB #-}
 enumDeltaIntegerFB :: (Integer -> b -> b) -> Integer -> Integer -> b
-enumDeltaIntegerFB c x d = go x
+enumDeltaIntegerFB c x0 d = go x0
   where go x = x `seq` (x `c` go (x+d))
 
 {-# NOINLINE [1] enumDeltaInteger #-}
diff --git a/libraries/base/GHC/GHCi.hs b/libraries/base/GHC/GHCi.hs
index 56874a5..514a33c 100644
--- a/libraries/base/GHC/GHCi.hs
+++ b/libraries/base/GHC/GHCi.hs
@@ -21,7 +21,7 @@ module GHC.GHCi {-# WARNING "This is an unstable interface." #-} (
         GHCiSandboxIO(..), NoIO()
     ) where
 
-import GHC.Base (IO(), Monad, Functor(fmap), Applicative(..), (>>=), return, id, (.), ap)
+import GHC.Base (IO(), Monad, Functor(fmap), Applicative(..), (>>=), id, (.), ap)
 
 -- | A monad that can execute GHCi statements by lifting them out of
 -- m into the IO monad. (e.g state monads)
diff --git a/mk/warnings.mk b/mk/warnings.mk
index 2e82428..267aef6 100644
--- a/mk/warnings.mk
+++ b/mk/warnings.mk
@@ -25,9 +25,6 @@ SRC_CC_WARNING_OPTS += -Wno-unknown-pragmas
 
 endif
 
-SRC_CC_OPTS     += -Wall
-SRC_HC_OPTS     += -Wall
-
 GhcStage1HcOpts += -fwarn-tabs
 GhcStage2HcOpts += -fwarn-tabs