From e6c803f702e8b09dfd0073b973b8afcd7071db50 Mon Sep 17 00:00:00 2001
From: Rodrigo Mesquita <rodrigo.m.mesquita@gmail.com>
Date: Wed, 8 Nov 2023 13:54:54 +0000
Subject: [PATCH] darwin: Fix single_module is obsolete warning
In XCode 15's linker, -single_module is the default and otherwise
passing it as a flag results in a warning being raised:
ld: warning: -single_module is obsolete
This patch fixes this warning by, at configure time, determining whether
the linker supports -single_module (which is likely false for all
non-darwin linkers, and true for darwin linkers in previous versions of
macOS), and using that information at runtime to decide to pass or not
the flag in the invocation.
Fixes #24168
---
compiler/GHC/Linker/Dynamic.hs | 11 ++++--
compiler/GHC/Settings.hs | 1 +
compiler/GHC/Settings/IO.hs | 2 ++
configure.ac | 1 +
distrib/configure.ac.in | 1 +
hadrian/bindist/Makefile | 1 +
hadrian/bindist/config.mk.in | 1 +
hadrian/cfg/default.host.target.in | 1 +
hadrian/cfg/default.target.in | 1 +
hadrian/src/Rules/Generate.hs | 2 ++
m4/fp_prog_ld_single_module.m4 | 30 ++++++++++++++++
m4/prep_target_file.m4 | 1 +
.../src/GHC/Toolchain/Tools/Link.hs | 34 ++++++++++++++++++-
13 files changed, 84 insertions(+), 3 deletions(-)
create mode 100644 m4/fp_prog_ld_single_module.m4
diff --git a/compiler/GHC/Linker/Dynamic.hs b/compiler/GHC/Linker/Dynamic.hs
index 7cfd797d6b06..053a2ca89006 100644
--- a/compiler/GHC/Linker/Dynamic.hs
+++ b/compiler/GHC/Linker/Dynamic.hs
@@ -11,6 +11,7 @@ where
import GHC.Prelude
import GHC.Platform
import GHC.Platform.Ways
+import GHC.Settings (ToolSettings(toolSettings_ldSupportsSingleModule))
import GHC.Driver.Config.Linker
import GHC.Driver.Session
@@ -152,6 +153,9 @@ linkDynLib logger tmpfs dflags0 unit_env o_files dep_packages
-- dynamic binding nonsense when referring to symbols from
-- within the library. The NCG assumes that this option is
-- specified (on i386, at least).
+ -- In XCode 15, -single_module is the default and passing the
+ -- flag is now obsolete and raises a warning (#24168). We encode
+ -- this information into the toolchain field ...SupportsSingleModule.
-- -install_name
-- Mac OS/X stores the path where a dynamic library is (to
-- be) installed in the library itself. It's called the
@@ -177,8 +181,11 @@ linkDynLib logger tmpfs dflags0 unit_env o_files dep_packages
]
++ map Option o_files
++ [ Option "-undefined",
- Option "dynamic_lookup",
- Option "-single_module" ]
+ Option "dynamic_lookup"
+ ]
+ ++ (if toolSettings_ldSupportsSingleModule (toolSettings dflags)
+ then [ Option "-single_module" ]
+ else [ ])
++ (if platformArch platform `elem` [ ArchX86_64, ArchAArch64 ]
then [ ]
else [ Option "-Wl,-read_only_relocs,suppress" ])
diff --git a/compiler/GHC/Settings.hs b/compiler/GHC/Settings.hs
index c1a9d4d788c9..e2fc7338ecdf 100644
--- a/compiler/GHC/Settings.hs
+++ b/compiler/GHC/Settings.hs
@@ -86,6 +86,7 @@ data Settings = Settings
data ToolSettings = ToolSettings
{ toolSettings_ldSupportsCompactUnwind :: Bool
, toolSettings_ldSupportsFilelist :: Bool
+ , toolSettings_ldSupportsSingleModule :: Bool
, toolSettings_mergeObjsSupportsResponseFiles :: Bool
, toolSettings_ldIsGnuLd :: Bool
, toolSettings_ccSupportsNoPie :: Bool
diff --git a/compiler/GHC/Settings/IO.hs b/compiler/GHC/Settings/IO.hs
index e765e2e5cfb8..dedd6fb9af12 100644
--- a/compiler/GHC/Settings/IO.hs
+++ b/compiler/GHC/Settings/IO.hs
@@ -107,6 +107,7 @@ initSettings top_dir = do
ldSupportsCompactUnwind <- getBooleanSetting "ld supports compact unwind"
ldSupportsFilelist <- getBooleanSetting "ld supports filelist"
+ ldSupportsSingleModule <- getBooleanSetting "ld supports single module"
mergeObjsSupportsResponseFiles <- getBooleanSetting "Merge objects supports response files"
ldIsGnuLd <- getBooleanSetting "ld is GNU ld"
arSupportsDashL <- getBooleanSetting "ar supports -L"
@@ -171,6 +172,7 @@ initSettings top_dir = do
, sToolSettings = ToolSettings
{ toolSettings_ldSupportsCompactUnwind = ldSupportsCompactUnwind
, toolSettings_ldSupportsFilelist = ldSupportsFilelist
+ , toolSettings_ldSupportsSingleModule = ldSupportsSingleModule
, toolSettings_mergeObjsSupportsResponseFiles = mergeObjsSupportsResponseFiles
, toolSettings_ldIsGnuLd = ldIsGnuLd
, toolSettings_ccSupportsNoPie = gccSupportsNoPie
diff --git a/configure.ac b/configure.ac
index 3a6dfd32da86..36a754d75eea 100644
--- a/configure.ac
+++ b/configure.ac
@@ -452,6 +452,7 @@ CFLAGS="$CFLAGS $GccUseLdOpt"
FP_PROG_LD_IS_GNU
FP_PROG_LD_NO_COMPACT_UNWIND
FP_PROG_LD_FILELIST
+FP_PROG_LD_SINGLE_MODULE
dnl ** Which nm to use?
diff --git a/distrib/configure.ac.in b/distrib/configure.ac.in
index ecbfebef5784..8a2016c1c8fa 100644
--- a/distrib/configure.ac.in
+++ b/distrib/configure.ac.in
@@ -136,6 +136,7 @@ CFLAGS="$CFLAGS $GccUseLdOpt"
FP_PROG_LD_IS_GNU
FP_PROG_LD_NO_COMPACT_UNWIND
FP_PROG_LD_FILELIST
+FP_PROG_LD_SINGLE_MODULE
dnl ** which strip to use?
dnl --------------------------------------------------------------
diff --git a/hadrian/bindist/Makefile b/hadrian/bindist/Makefile
index 31fe94c72b1b..293a0bfdd380 100644
--- a/hadrian/bindist/Makefile
+++ b/hadrian/bindist/Makefile
@@ -104,6 +104,7 @@ lib/settings : config.mk
@echo ',("Haskell CPP flags", "$(SettingsHaskellCPPFlags)")' >> $@
@echo ',("ld supports compact unwind", "$(LdHasNoCompactUnwind)")' >> $@
@echo ',("ld supports filelist", "$(LdHasFilelist)")' >> $@
+ @echo ',("ld supports single module", "$(LdHasSingleModule)")' >> $@
@echo ',("ld is GNU ld", "$(LdIsGNULd)")' >> $@
@echo ',("Merge objects command", "$(SettingsMergeObjectsCommand)")' >> $@
@echo ',("Merge objects flags", "$(SettingsMergeObjectsFlags)")' >> $@
diff --git a/hadrian/bindist/config.mk.in b/hadrian/bindist/config.mk.in
index 4a21d7d0e437..fd158c411948 100644
--- a/hadrian/bindist/config.mk.in
+++ b/hadrian/bindist/config.mk.in
@@ -191,6 +191,7 @@ LdHasBuildId = @LdHasBuildId@
LdHasFilelist = @LdHasFilelist@
LdIsGNULd = @LdIsGNULd@
LdHasNoCompactUnwind = @LdHasNoCompactUnwind@
+LdHasSingleModule = @LdHasSingleModule@
ArArgs = @ArArgs@
ArSupportsAtFile = @ArSupportsAtFile@
ArSupportsDashL = @ArSupportsDashL@
diff --git a/hadrian/cfg/default.host.target.in b/hadrian/cfg/default.host.target.in
index e38e20cda7a9..eaf01470c887 100644
--- a/hadrian/cfg/default.host.target.in
+++ b/hadrian/cfg/default.host.target.in
@@ -21,6 +21,7 @@ Target
, ccLinkSupportsNoPie = False
, ccLinkSupportsCompactUnwind = False
, ccLinkSupportsFilelist = False
+, ccLinkSupportsSingleModule = True
, ccLinkIsGnu = False
}
diff --git a/hadrian/cfg/default.target.in b/hadrian/cfg/default.target.in
index 84da17bc160d..a9888a2df4ac 100644
--- a/hadrian/cfg/default.target.in
+++ b/hadrian/cfg/default.target.in
@@ -21,6 +21,7 @@ Target
, ccLinkSupportsNoPie = @CONF_GCC_SUPPORTS_NO_PIEBool@
, ccLinkSupportsCompactUnwind = @LdHasNoCompactUnwindBool@
, ccLinkSupportsFilelist = @LdHasFilelistBool@
+, ccLinkSupportsSingleModule = @LdHasSingleModuleBool@
, ccLinkIsGnu = @LdIsGNULdBool@
}
diff --git a/hadrian/src/Rules/Generate.hs b/hadrian/src/Rules/Generate.hs
index 5787e2054e81..bf84da2f9de3 100644
--- a/hadrian/src/Rules/Generate.hs
+++ b/hadrian/src/Rules/Generate.hs
@@ -373,6 +373,7 @@ generateSettings = do
, ("Haskell CPP flags", queryTarget hsCppFlags)
, ("ld supports compact unwind", queryTarget linkSupportsCompactUnwind)
, ("ld supports filelist", queryTarget linkSupportsFilelist)
+ , ("ld supports single module", queryTarget linkSupportsSingleModule)
, ("ld is GNU ld", queryTarget linkIsGnu)
, ("Merge objects command", queryTarget mergeObjsPath)
, ("Merge objects flags", queryTarget mergeObjsFlags)
@@ -431,6 +432,7 @@ generateSettings = do
hsCppFlags = unwords . prgFlags . hsCppProgram . tgtHsCPreprocessor
mergeObjsPath = maybe "" (prgPath . mergeObjsProgram) . tgtMergeObjs
mergeObjsFlags = maybe "" (unwords . prgFlags . mergeObjsProgram) . tgtMergeObjs
+ linkSupportsSingleModule = yesNo . ccLinkSupportsSingleModule . tgtCCompilerLink
linkSupportsFilelist = yesNo . ccLinkSupportsFilelist . tgtCCompilerLink
linkSupportsCompactUnwind = yesNo . ccLinkSupportsCompactUnwind . tgtCCompilerLink
linkIsGnu = yesNo . ccLinkIsGnu . tgtCCompilerLink
diff --git a/m4/fp_prog_ld_single_module.m4 b/m4/fp_prog_ld_single_module.m4
new file mode 100644
index 000000000000..3e124c81ca3e
--- /dev/null
+++ b/m4/fp_prog_ld_single_module.m4
@@ -0,0 +1,30 @@
+# FP_PROG_LD_SINGLE_MODULE
+# ----------------------------
+# Sets the output variable LdHasSingleModule to YES if the darwin ld supports
+# -single_module, or NO otherwise.
+#
+# In XCode 15, -single_module is a default and passing it as a flag raises a
+# warning.
+AC_DEFUN([FP_PROG_LD_SINGLE_MODULE],
+[
+AC_CACHE_CHECK([whether ld supports -single_module], [fp_cv_ld_single_module],
+[
+case $target in
+ *-darwin)
+ echo 'int foo(int x) { return x*x; }' > conftest.c
+ echo 'extern int foo(int); int main() { return foo(5); }' > conftestmain.c
+ "$CC" -c -o conftestmain.o conftestmain.c
+ "$CC" -shared -o conftest.dylib conftest.c
+ if "$CC" -Wl,-single_module -o conftest conftestmain.o conftest.dylib 2>&1 | grep obsolete > /dev/null; then
+ fp_cv_ld_single_module=no
+ else
+ fp_cv_ld_single_module=yes
+ fi
+ rm -rf conftest* ;;
+ *)
+ fp_cv_ld_single_module=no ;;
+esac
+])
+FP_CAPITALIZE_YES_NO(["$fp_cv_ld_single_module"], [LdHasSingleModule])
+AC_SUBST([LdHasSingleModule])
+])# FP_PROG_LD_SINGLE_MODULE
diff --git a/m4/prep_target_file.m4 b/m4/prep_target_file.m4
index 89e773f75127..2cee899c1620 100644
--- a/m4/prep_target_file.m4
+++ b/m4/prep_target_file.m4
@@ -131,6 +131,7 @@ AC_DEFUN([PREP_TARGET_FILE],[
PREP_BOOLEAN([TargetHasIdentDirective])
PREP_BOOLEAN([CONF_GCC_SUPPORTS_NO_PIE])
PREP_BOOLEAN([LdHasFilelist])
+ PREP_BOOLEAN([LdHasSingleModule])
PREP_BOOLEAN([LdIsGNULd])
PREP_BOOLEAN([LdHasNoCompactUnwind])
PREP_BOOLEAN([TargetHasSubsectionsViaSymbols])
diff --git a/utils/ghc-toolchain/src/GHC/Toolchain/Tools/Link.hs b/utils/ghc-toolchain/src/GHC/Toolchain/Tools/Link.hs
index 080427c7d634..3dcf24745884 100644
--- a/utils/ghc-toolchain/src/GHC/Toolchain/Tools/Link.hs
+++ b/utils/ghc-toolchain/src/GHC/Toolchain/Tools/Link.hs
@@ -22,6 +22,7 @@ data CcLink = CcLink { ccLinkProgram :: Program
, ccLinkSupportsNoPie :: Bool -- See Note [No PIE when linking] in GHC.Driver.Session
, ccLinkSupportsCompactUnwind :: Bool
, ccLinkSupportsFilelist :: Bool
+ , ccLinkSupportsSingleModule :: Bool
, ccLinkIsGnu :: Bool
}
deriving (Read, Eq, Ord)
@@ -34,6 +35,7 @@ instance Show CcLink where
, ", ccLinkSupportsNoPie = " ++ show ccLinkSupportsNoPie
, ", ccLinkSupportsCompactUnwind = " ++ show ccLinkSupportsCompactUnwind
, ", ccLinkSupportsFilelist = " ++ show ccLinkSupportsFilelist
+ , ", ccLinkSupportsSingleModule = " ++ show ccLinkSupportsSingleModule
, ", ccLinkIsGnu = " ++ show ccLinkIsGnu
, "}"
]
@@ -66,12 +68,13 @@ findCcLink target ld progOpt ldOverride archOs cc readelf = checking "for C comp
ccLinkSupportsNoPie <- checkSupportsNoPie cc ccLinkProgram
ccLinkSupportsCompactUnwind <- checkSupportsCompactUnwind archOs cc ccLinkProgram
ccLinkSupportsFilelist <- checkSupportsFilelist cc ccLinkProgram
+ ccLinkSupportsSingleModule <- checkSupportsSingleModule archOs cc ccLinkProgram
ccLinkIsGnu <- checkLinkIsGnu archOs ccLinkProgram
checkBfdCopyBug archOs cc readelf ccLinkProgram
ccLinkProgram <- addPlatformDepLinkFlags archOs cc ccLinkProgram
let ccLink = CcLink {ccLinkProgram, ccLinkSupportsNoPie,
ccLinkSupportsCompactUnwind, ccLinkSupportsFilelist,
- ccLinkIsGnu}
+ ccLinkSupportsSingleModule, ccLinkIsGnu}
ccLink <- linkRequiresNoFixupChains archOs cc ccLink
ccLink <- linkRequiresNoWarnDuplicateLibraries archOs cc ccLink
return ccLink
@@ -164,6 +167,35 @@ checkSupportsFilelist cc ccLink = checking "whether the cc linker understands -f
return (isSuccess exitCode)
+-- | Check that the (darwin) linker supports @-single_module@.
+--
+-- In XCode 15, the linker warns when @-single_module@ is passed as the flag
+-- became the default and is now obsolete to pass.
+--
+-- We assume non-darwin linkers don't support this flag.
+checkSupportsSingleModule :: ArchOS -> Cc -> Program -> M Bool
+checkSupportsSingleModule archOs cc link
+ | ArchOS _ OSDarwin <- archOs
+ = checking "whether the darwin linker supports -single_module" $ do
+ withTempDir $ \dir -> do
+ let test_dylib = dir </> "test.dylib"
+ test_c = dir </> "test.c"
+ testmain_o = dir </> "testmain.o"
+ testmain = dir </> "testmain"
+
+ -- Main
+ compileC cc testmain_o "extern int foo(int); int main() { return foo(5); }"
+
+ -- Dynamic library
+ writeFile test_c "int foo(int x) { return x*x; }"
+ _ <- runProgram (ccProgram cc) ["-shared", "-o", test_dylib, test_c]
+
+ (_, out, err) <- readProgram link ["-Wl,-single_module", "-o", testmain, test_dylib, testmain_o]
+
+ return $ not $ "obsolete" `isInfixOf` err || "obsolete" `isInfixOf` out
+ | otherwise
+ = return False
+
-- | Check whether linking works.
checkLinkWorks :: Cc -> Program -> M ()
checkLinkWorks cc ccLink = withTempDir $ \dir -> do
--
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