Enable response files for linker if supported

8 files changed, 31 insertions, 4 deletions

diff --git a/compiler/GHC/Settings.hs b/compiler/GHC/Settings.hs
index 291c77b860..c2b34b0c10 100644
--- a/compiler/GHC/Settings.hs
+++ b/compiler/GHC/Settings.hs
@@ -19,6 +19,7 @@ module GHC.Settings
   , sGlobalPackageDatabasePath
   , sLdSupportsCompactUnwind
   , sLdSupportsFilelist
+  , sLdSupportsResponseFiles
   , sLdIsGnuLd
   , sGccSupportsNoPie
   , sUseInplaceMinGW
@@ -87,6 +88,7 @@ data Settings = Settings
 data ToolSettings = ToolSettings
   { toolSettings_ldSupportsCompactUnwind :: Bool
   , toolSettings_ldSupportsFilelist      :: Bool
+  , toolSettings_ldSupportsResponseFiles :: Bool
   , toolSettings_ldIsGnuLd               :: Bool
   , toolSettings_ccSupportsNoPie         :: Bool
   , toolSettings_useInplaceMinGW         :: Bool
@@ -189,6 +191,8 @@ sLdSupportsCompactUnwind :: Settings -> Bool
 sLdSupportsCompactUnwind = toolSettings_ldSupportsCompactUnwind . sToolSettings
 sLdSupportsFilelist :: Settings -> Bool
 sLdSupportsFilelist = toolSettings_ldSupportsFilelist . sToolSettings
+sLdSupportsResponseFiles :: Settings -> Bool
+sLdSupportsResponseFiles = toolSettings_ldSupportsResponseFiles . sToolSettings
 sLdIsGnuLd :: Settings -> Bool
 sLdIsGnuLd = toolSettings_ldIsGnuLd . sToolSettings
 sGccSupportsNoPie :: Settings -> Bool
diff --git a/compiler/GHC/Settings/IO.hs b/compiler/GHC/Settings/IO.hs
index 06952774fd..31c3164bc1 100644
--- a/compiler/GHC/Settings/IO.hs
+++ b/compiler/GHC/Settings/IO.hs
@@ -95,6 +95,7 @@ initSettings top_dir = do
       cxx_args = words cxx_args_str
   ldSupportsCompactUnwind <- getBooleanSetting "ld supports compact unwind"
   ldSupportsFilelist      <- getBooleanSetting "ld supports filelist"
+  ldSupportsResponseFiles <- getBooleanSetting "ld supports response files"
   ldIsGnuLd               <- getBooleanSetting "ld is GNU ld"
   arSupportsDashL         <- getBooleanSetting "ar supports -L"
 
@@ -163,6 +164,7 @@ initSettings top_dir = do
     , sToolSettings = ToolSettings
       { toolSettings_ldSupportsCompactUnwind = ldSupportsCompactUnwind
       , toolSettings_ldSupportsFilelist      = ldSupportsFilelist
+      , toolSettings_ldSupportsResponseFiles = ldSupportsResponseFiles
       , toolSettings_ldIsGnuLd               = ldIsGnuLd
       , toolSettings_ccSupportsNoPie         = gccSupportsNoPie
       , toolSettings_useInplaceMinGW         = useInplaceMinGW
diff --git a/compiler/GHC/SysTools/Tasks.hs b/compiler/GHC/SysTools/Tasks.hs
index 66f0346886..463cf39145 100644
--- a/compiler/GHC/SysTools/Tasks.hs
+++ b/compiler/GHC/SysTools/Tasks.hs
@@ -29,7 +29,6 @@ import GHC.Utils.Outputable
 import GHC.Utils.Misc
 import GHC.Utils.Logger
 import GHC.Utils.TmpFs
-import GHC.Utils.Constants (isWindowsHost)
 import GHC.Utils.Panic
 
 import Data.List (tails, isPrefixOf)
@@ -350,9 +349,7 @@ runMergeObjects logger tmpfs dflags args =
             , "does not support object merging." ]
         optl_args = map Option (getOpts dflags opt_lm)
         args2     = args0 ++ args ++ optl_args
-    -- N.B. Darwin's ld64 doesn't support response files. Consequently we only
-    -- use them on Windows where they are truly necessary.
-    if isWindowsHost
+    if toolSettings_ldSupportsResponseFiles (toolSettings dflags)
       then do
         mb_env <- getGccEnv args2
         runSomethingResponseFile logger tmpfs dflags id "Merge objects" p args2 mb_env
diff --git a/configure.ac b/configure.ac
index 99a91e42d6..a0df24a50a 100644
--- a/configure.ac
+++ b/configure.ac
@@ -663,6 +663,8 @@ FP_LD_NO_FIXUP_CHAINS([build], [CONF_GCC_LINKER_OPTS_STAGE0])
 FP_LD_NO_FIXUP_CHAINS([target], [CONF_GCC_LINKER_OPTS_STAGE1])
 FP_LD_NO_FIXUP_CHAINS([target], [CONF_GCC_LINKER_OPTS_STAGE2])
 
+FP_LD_SUPPORTS_RESPONSE_FILES()
+
 GHC_LLVM_TARGET_SET_VAR
 # we intend to pass trough --targets to llvm as is.
 LLVMTarget_CPP=`    echo "$LlvmTarget"`
diff --git a/hadrian/bindist/Makefile b/hadrian/bindist/Makefile
index f36ffa57c0..274772e80a 100644
--- a/hadrian/bindist/Makefile
+++ b/hadrian/bindist/Makefile
@@ -92,6 +92,7 @@ lib/settings : config.mk
 	@echo ',("ld flags", "$(SettingsLdFlags)")' >> $@
 	@echo ',("ld supports compact unwind", "$(LdHasNoCompactUnwind)")' >> $@
 	@echo ',("ld supports filelist", "$(LdHasFilelist)")' >> $@
+	@echo ',("ld supports response files", "$(LdSupportsResponseFiles)")' >> $@
 	@echo ',("ld is GNU ld", "$(LdIsGNULd)")' >> $@
 	@echo ',("Merge objects command", "$(SettingsMergeObjectsCommand)")' >> $@
 	@echo ',("Merge objects flags", "$(SettingsMergeObjectsFlags)")' >> $@
diff --git a/hadrian/cfg/system.config.in b/hadrian/cfg/system.config.in
index 6a891b4363..57c57aa057 100644
--- a/hadrian/cfg/system.config.in
+++ b/hadrian/cfg/system.config.in
@@ -140,6 +140,7 @@ conf-merge-objects-args-stage3  = @MergeObjsArgs@
 gcc-extra-via-c-opts = @GccExtraViaCOpts@
 ld-has-no-compact-unwind = @LdHasNoCompactUnwind@
 ld-has-filelist = @LdHasFilelist@
+ld-supports-response-files = @LdSupportsResponseFiles@
 ld-is-gnu-ld = @LdIsGNULd@
 ar-args = @ArArgs@
 
diff --git a/hadrian/src/Rules/Generate.hs b/hadrian/src/Rules/Generate.hs
index fbd6f8d9aa..1e905438eb 100644
--- a/hadrian/src/Rules/Generate.hs
+++ b/hadrian/src/Rules/Generate.hs
@@ -427,6 +427,7 @@ generateSettings = do
         , ("ld flags", expr $ settingsFileSetting SettingsFileSetting_LdFlags)
         , ("ld supports compact unwind", expr $ lookupSystemConfig "ld-has-no-compact-unwind")
         , ("ld supports filelist", expr $ lookupSystemConfig "ld-has-filelist")
+        , ("ld supports response files", expr $ lookupSystemConfig "ld-supports-response-files")
         , ("ld is GNU ld", expr $ lookupSystemConfig "ld-is-gnu-ld")
         , ("Merge objects command", expr $ settingsFileSetting SettingsFileSetting_MergeObjectsCommand)
         , ("Merge objects flags", expr $ settingsFileSetting SettingsFileSetting_MergeObjectsFlags)
diff --git a/m4/fp_ld_supports_response_files.m4 b/m4/fp_ld_supports_response_files.m4
new file mode 100644
index 0000000000..5596169dcb
--- /dev/null
+++ b/m4/fp_ld_supports_response_files.m4
@@ -0,0 +1,19 @@
+# FP_LD_SUPPORTS_RESPONSE_FILES
+# --------------------
+# See if whether we are using a version of ld64 on darwin platforms which
+# supports response files.
+AC_DEFUN([FP_LD_SUPPORTS_RESPONSE_FILES], [
+    AC_MSG_CHECKING([whether $LD supports response files])
+    echo 'int main(void) {return 0;}' > conftest.c
+    $CC -c -o conftest.o conftest.c > /dev/null 2>&1
+    if $LD @<(printf '%q\n' -o conftest conftest.o) > /dev/null 2>&1
+    then
+        LdSupportsResponseFiles=YES
+        AC_MSG_RESULT([yes])
+    else
+        LdSupportsResponseFiles=NO
+        AC_MSG_RESULT([no])
+    fi
+    rm -f conftest.c conftest
+    AC_SUBST(LdSupportsResponseFiles)
+])