[commit: ghc] master: Remove warnings-silencing flags for code generated by Alex (699e507)
git at git.haskell.org
git at git.haskell.org
Thu Nov 22 18:47:28 UTC 2018
Repository : ssh://git@git.haskell.org/ghc
On branch : master
Link : http://ghc.haskell.org/trac/ghc/changeset/699e507237ccda65fe9f37651d2358129390e2de/ghc
>---------------------------------------------------------------
commit 699e507237ccda65fe9f37651d2358129390e2de
Author: Simon Jakobi <simon.jakobi at gmail.com>
Date: Thu Nov 22 11:52:53 2018 -0500
Remove warnings-silencing flags for code generated by Alex
Current versions of Alex don't seem to produce as many warnings any
more.
In order to silence a warning and to avoid overlong lines, I've taken
the liberty of refactoring 'tok_num'.
Test Plan: ./validate
Reviewers: bgamari, simonmar
Reviewed By: simonmar
Subscribers: erikd, rwbarton, carter
Differential Revision: https://phabricator.haskell.org/D5319
>---------------------------------------------------------------
699e507237ccda65fe9f37651d2358129390e2de
aclocal.m4 | 10 ++-------
compiler/cmm/CmmLex.x | 7 ------
compiler/parser/Lexer.x | 54 ++++++++-------------------------------------
mk/config.mk.in | 3 ---
utils/genprimopcode/Lexer.x | 8 -------
5 files changed, 11 insertions(+), 71 deletions(-)
diff --git a/aclocal.m4 b/aclocal.m4
index 18e0d7e..447fd61 100644
--- a/aclocal.m4
+++ b/aclocal.m4
@@ -958,16 +958,10 @@ else
fi;
changequote([, ])dnl
])
-FP_COMPARE_VERSIONS([$fptools_cv_alex_version],[-ge],[3.0],
- [Alex3=YES],[Alex3=NO])
-if test ! -f compiler/cmm/CmmLex.hs || test ! -f compiler/parser/Lexer.hs
-then
- FP_COMPARE_VERSIONS([$fptools_cv_alex_version],[-lt],[3.1.0],
- [AC_MSG_ERROR([Alex version 3.1.0 or later is required to compile GHC.])])[]
-fi
+FP_COMPARE_VERSIONS([$fptools_cv_alex_version],[-lt],[3.1.7],
+ [AC_MSG_ERROR([Alex version 3.1.7 or later is required to compile GHC.])])[]
AlexVersion=$fptools_cv_alex_version;
AC_SUBST(AlexVersion)
-AC_SUBST(Alex3)
])
diff --git a/compiler/cmm/CmmLex.x b/compiler/cmm/CmmLex.x
index 691ca5e..468ea00 100644
--- a/compiler/cmm/CmmLex.x
+++ b/compiler/cmm/CmmLex.x
@@ -11,13 +11,6 @@
-----------------------------------------------------------------------------
{
--- See Note [Warnings in code generated by Alex] in compiler/parser/Lexer.x
-{-# OPTIONS_GHC -fno-warn-unused-matches #-}
-{-# OPTIONS_GHC -fno-warn-unused-binds #-}
-{-# OPTIONS_GHC -fno-warn-unused-imports #-}
-{-# OPTIONS_GHC -fno-warn-tabs #-}
-{-# OPTIONS_GHC -fno-warn-missing-signatures #-}
-
module CmmLex (
CmmToken(..), cmmlex,
) where
diff --git a/compiler/parser/Lexer.x b/compiler/parser/Lexer.x
index f99a344..9597f10 100644
--- a/compiler/parser/Lexer.x
+++ b/compiler/parser/Lexer.x
@@ -42,13 +42,7 @@
{
{-# LANGUAGE BangPatterns #-}
-
--- See Note [Warnings in code generated by Alex] in compiler/parser/Lexer.x
-{-# OPTIONS_GHC -fno-warn-unused-matches #-}
-{-# OPTIONS_GHC -fno-warn-unused-binds #-}
-{-# OPTIONS_GHC -fno-warn-unused-imports #-}
-{-# OPTIONS_GHC -fno-warn-tabs #-}
-{-# OPTIONS_GHC -fno-warn-missing-signatures #-}
+{-# LANGUAGE LambdaCase #-}
{-# OPTIONS_GHC -funbox-strict-fields #-}
@@ -1388,13 +1382,15 @@ tok_integral itint transint transbuf translen (radix,char_to_int) span buf len =
(offsetBytes transbuf buf) (subtract translen len) radix char_to_int
tok_num :: (Integer -> Integer)
- -> Int -> Int
- -> (Integer, (Char->Int)) -> Action
-tok_num = tok_integral itint
+ -> Int -> Int
+ -> (Integer, (Char->Int)) -> Action
+tok_num = tok_integral $ \case
+ st@(SourceText ('-':_)) -> itint st (const True)
+ st@(SourceText _) -> itint st (const False)
+ st at NoSourceText -> itint st (< 0)
where
- itint st@(SourceText ('-':str)) val = ITinteger (((IL $! st) $! True) $! val)
- itint st@(SourceText str ) val = ITinteger (((IL $! st) $! False) $! val)
- itint st@(NoSourceText ) val = ITinteger (((IL $! st) $! (val < 0)) $! val)
+ itint :: SourceText -> (Integer -> Bool) -> Integer -> Token
+ itint !st is_negative !val = ITinteger ((IL st $! is_negative val) val)
tok_primint :: (Integer -> Integer)
-> Int -> Int
@@ -3114,36 +3110,4 @@ isDocComment (ITdocCommentNamed _) = True
isDocComment (ITdocSection _ _) = True
isDocComment (ITdocOptions _) = True
isDocComment _ = False
-
-{- Note [Warnings in code generated by Alex]
-
-We add the following warning suppression flags to all code generated by Alex:
-
-{-# OPTIONS_GHC -fno-warn-unused-matches #-}
-{-# OPTIONS_GHC -fno-warn-unused-binds #-}
-{-# OPTIONS_GHC -fno-warn-unused-imports #-}
-{-# OPTIONS_GHC -fno-warn-tabs #-}
-{-# OPTIONS_GHC -fno-warn-missing-signatures #-}
-
-Without these flags, current versions of Alex will generate code that is not
-warning free. Note that this is the result of Alex' internals, not of the way
-we have written our (Lexer).x files.
-
-As always, we need code to be warning free when validating with -Werror.
-
-The list of flags is as short as possible (at the time of writing), to try to
-avoid suppressing warnings for bugs in our own code.
-
-TODO. Reevaluate this situation once Alex >3.1.4 is released. Hopefully you
-can remove these flags from all (Lexer).x files in the repository, and also
-delete this Note. Don't forget to update aclocal.m4, and send a HEADS UP
-message to ghc-devs.
-
-The first release of Alex after 3.1.4 will either suppress all warnings itself
-[1] (bad), or most warnings will be fixed and only a few select ones will be
-suppressed by default [2] (better).
-
-[1] https://github.com/simonmar/alex/commit/1eefcde22ba1bb9b51d523814415714e20f0761e
-[2] https://github.com/simonmar/alex/pull/69
--}
}
diff --git a/mk/config.mk.in b/mk/config.mk.in
index 7fa0f77..fb823ae 100644
--- a/mk/config.mk.in
+++ b/mk/config.mk.in
@@ -859,16 +859,13 @@ SRC_HAPPY_OPTS = -agc --strict
#
ALEX = @AlexCmd@
ALEX_VERSION = @AlexVersion@
-Alex3 = @Alex3@
#
# Options to pass to Alex when we're going to compile the output with GHC
#
SRC_ALEX_OPTS = -g
-ifeq "$(Alex3)" "YES"
# The compiler isn't using the Unicode support in Alex 3.0 yet, in fact we do our own
# Unicode handling, so diable Alex's.
compiler_ALEX_OPTS = --latin1
-endif
# Should we build haddock docs?
HADDOCK_DOCS = YES
diff --git a/utils/genprimopcode/Lexer.x b/utils/genprimopcode/Lexer.x
index 06624b2..0de81f9 100644
--- a/utils/genprimopcode/Lexer.x
+++ b/utils/genprimopcode/Lexer.x
@@ -1,12 +1,4 @@
-
{
--- See Note [Warnings in code generated by Alex] in compiler/parser/Lexer.x
-{-# OPTIONS_GHC -fno-warn-unused-matches #-}
-{-# OPTIONS_GHC -fno-warn-unused-binds #-}
-{-# OPTIONS_GHC -fno-warn-tabs #-}
-{-# OPTIONS_GHC -fno-warn-missing-signatures #-}
-{-# OPTIONS_GHC -fno-warn-unused-imports #-}
-
module Lexer (lex_tok) where
import ParserM (ParserM (..), mkT, mkTv, Token(..), start_code,
More information about the ghc-commits
mailing list