diff mbox series

[v3,2/2] Use $(LD) instead of $(CC) for linking the object files

Message ID 7d33e11867e0a75efb1a906610ff81da2ace9717.1599704262.git.gitgitgadget@gmail.com
State New
Headers show
Series Fit the building tools to Plan 9 environment | expand

Commit Message

Elijah Newren via GitGitGadget Sept. 10, 2020, 2:17 a.m. UTC
From: Kyohei Kadota <lufia@lufia.org>

Plan 9's loader(aka. linker) is separated from the compiler.
The compilers are called 8c, 6c... for each machine architectures;
corresponded loaders are called 8l, 6l...

Signed-off-by: Kyohei Kadota <lufia@lufia.org>
---
 .github/workflows/main.yml |  1 +
 Makefile                   | 15 ++++++++-------
 ci/lib.sh                  |  8 +++++++-
 config.mak.in              |  1 +
 config.mak.uname           |  6 ++++++
 5 files changed, 23 insertions(+), 8 deletions(-)

Comments

Junio C Hamano Sept. 10, 2020, 5:31 a.m. UTC | #1
"Kyohei Kadota via GitGitGadget" <gitgitgadget@gmail.com> writes:

> diff --git a/Makefile b/Makefile
> index 86e5411f39..c0c0c280f0 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -543,6 +543,7 @@ export prefix bindir sharedir sysconfdir gitwebdir perllibdir localedir
>  
>  # Set our default programs
>  CC = cc
> +LD = cc

This is good that any system that use 'cc' to link now will reach
the same 'cc' via $(LD) instead of $(CC).

But those who customize $(CC) to their taste now needs to override
not just CC but also LD.  Can we avoid regressing for them?  Perhaps
default the value of LD to $(CC) instead of hardcoded 'cc'?

> @@ -2121,7 +2122,7 @@ git.sp git.s git.o: EXTRA_CPPFLAGS = \
>  	'-DGIT_INFO_PATH="$(infodir_relative_SQ)"'
>  
>  git$X: git.o GIT-LDFLAGS $(BUILTIN_OBJS) $(GITLIBS)
> -	$(QUIET_LINK)$(CC) $(ALL_CFLAGS) -o $@ $(ALL_LDFLAGS) \
> +	$(QUIET_LINK)$(LD) -o $@ $(ALL_LDFLAGS) \
>  		$(filter %.o,$^) $(LIBS)

Are there those who depended on ALL_CFLAGS on the command line when
the final linking happens?

For example, people have '-g -O2' on CFLAGS, and that will be
included in ALL_CFLAGS and passed to the final linking phase.  GNU
ld has "-O" option to optimize; when existing systems link with "cc
-g -O2 -o $@ ...", it is likely that "-O2" given to "cc" will cause
the "-O" option to be passed to underlying "ld".

But with the updated procedure (where LD is 'cc' for them), the
linkage will be done without ALL_CFLAGS passed on the command line,
and results in "cc -o $@ ...", without "-g -O2".

That sounds like a regression.

> @@ -2445,17 +2446,17 @@ compat/nedmalloc/nedmalloc.sp: SP_EXTRA_FLAGS += -Wno-non-pointer-null
>  endif
>  
>  git-%$X: %.o GIT-LDFLAGS $(GITLIBS)
> -	$(QUIET_LINK)$(CC) $(ALL_CFLAGS) -o $@ $(ALL_LDFLAGS) $(filter %.o,$^) $(LIBS)
> +	$(QUIET_LINK)$(LD) -o $@ $(ALL_LDFLAGS) $(filter %.o,$^) $(LIBS)
>  
>  git-imap-send$X: imap-send.o $(IMAP_SEND_BUILDDEPS) GIT-LDFLAGS $(GITLIBS)
> -	$(QUIET_LINK)$(CC) $(ALL_CFLAGS) -o $@ $(ALL_LDFLAGS) $(filter %.o,$^) \
> +	$(QUIET_LINK)$(LD) -o $@ $(ALL_LDFLAGS) $(filter %.o,$^) \
>  		$(IMAP_SEND_LDFLAGS) $(LIBS)
>  
>  git-http-fetch$X: http.o http-walker.o http-fetch.o GIT-LDFLAGS $(GITLIBS)
> -	$(QUIET_LINK)$(CC) $(ALL_CFLAGS) -o $@ $(ALL_LDFLAGS) $(filter %.o,$^) \
> +	$(QUIET_LINK)$(LD) -o $@ $(ALL_LDFLAGS) $(filter %.o,$^) \
>  		$(CURL_LIBCURL) $(LIBS)
>  git-http-push$X: http.o http-push.o GIT-LDFLAGS $(GITLIBS)
> -	$(QUIET_LINK)$(CC) $(ALL_CFLAGS) -o $@ $(ALL_LDFLAGS) $(filter %.o,$^) \
> +	$(QUIET_LINK)$(LD) -o $@ $(ALL_LDFLAGS) $(filter %.o,$^) \
>  		$(CURL_LIBCURL) $(EXPAT_LIBEXPAT) $(LIBS)
>  
>  $(REMOTE_CURL_ALIASES): $(REMOTE_CURL_PRIMARY)
> @@ -2465,7 +2466,7 @@ $(REMOTE_CURL_ALIASES): $(REMOTE_CURL_PRIMARY)
>  	cp $< $@
>  
>  $(REMOTE_CURL_PRIMARY): remote-curl.o http.o http-walker.o GIT-LDFLAGS $(GITLIBS)
> -	$(QUIET_LINK)$(CC) $(ALL_CFLAGS) -o $@ $(ALL_LDFLAGS) $(filter %.o,$^) \
> +	$(QUIET_LINK)$(LD) -o $@ $(ALL_LDFLAGS) $(filter %.o,$^) \
>  		$(CURL_LIBCURL) $(EXPAT_LIBEXPAT) $(LIBS)
>
> @@ -2753,7 +2754,7 @@ perf: all
>  t/helper/test-tool$X: $(patsubst %,t/helper/%,$(TEST_BUILTINS_OBJS))
>  
>  t/helper/test-%$X: t/helper/test-%.o GIT-LDFLAGS $(GITLIBS)
> -	$(QUIET_LINK)$(CC) $(ALL_CFLAGS) -o $@ $(ALL_LDFLAGS) $(filter %.o,$^) $(filter %.a,$^) $(LIBS)
> +	$(QUIET_LINK)$(LD) -o $@ $(ALL_LDFLAGS) $(filter %.o,$^) $(filter %.a,$^) $(LIBS)

Likewise for all of the above.

> diff --git a/ci/lib.sh b/ci/lib.sh
> index 3eefec500d..19c5beb277 100755
> --- a/ci/lib.sh
> +++ b/ci/lib.sh
> @@ -125,6 +125,7 @@ then

All changes to this file to pass LD=cc everywhere CC=cc is passed
look good to me.

> diff --git a/config.mak.in b/config.mak.in
> index e6a6d0f941..76ea7e781e 100644
> --- a/config.mak.in
> +++ b/config.mak.in
> @@ -2,6 +2,7 @@
>  # @configure_input@
>  
>  CC = @CC@
> +LD = @CC@
>  CFLAGS = @CFLAGS@
>  CPPFLAGS = @CPPFLAGS@
>  LDFLAGS = @LDFLAGS@

OK.

> diff --git a/config.mak.uname b/config.mak.uname
> index c7eba69e54..886ce068f8 100644
> --- a/config.mak.uname
> +++ b/config.mak.uname
> @@ -69,6 +69,7 @@ ifeq ($(uname_S),GNU/kFreeBSD)
>  endif
>  ifeq ($(uname_S),UnixWare)
>  	CC = cc
> +	LD = $(CC)
>  	NEEDS_SOCKET = YesPlease
>  	NEEDS_NSL = YesPlease
>  	NEEDS_SSL_WITH_CRYPTO = YesPlease
> @@ -90,6 +91,7 @@ ifeq ($(uname_S),SCO_SV)
>  	endif
>  	ifeq ($(uname_R),5)
>  		CC = cc
> +		LD = $(CC)
>  		BASIC_CFLAGS += -Kthread
>  	endif
>  	NEEDS_SOCKET = YesPlease
> @@ -435,6 +437,7 @@ ifeq ($(uname_S),Windows)
>  	DEFAULT_HELP_FORMAT = html
>  
>  	CC = compat/vcbuild/scripts/clink.pl
> +	LD = $(CC)
>  	AR = compat/vcbuild/scripts/lib.pl
>  	CFLAGS =
>  	BASIC_CFLAGS = -nologo -I. -Icompat/vcbuild/include -DWIN32 -D_CONSOLE -DHAVE_STRING_H -D_CRT_SECURE_NO_WARNINGS -D_CRT_NONSTDC_NO_DEPRECATE
> @@ -525,6 +528,7 @@ ifeq ($(uname_S),NONSTOP_KERNEL)
>  	ifeq ($(uname_R).$(uname_V),L17.02)
>  		CC += -WRVU=L16.05
>  	endif
> +	LD = $(CC)
>  	# Disable all optimization, seems to result in bad code, with -O or -O2
>  	# or even -O1 (default), /usr/local/libexec/git-core/git-pack-objects
>  	# abends on "git push". Needs more investigation.

Ditto.

> @@ -665,8 +669,10 @@ else
>  			BASIC_LDFLAGS += -Wl,--large-address-aware
>  		endif
>  		CC = gcc
> +		LD = $(CC)
>  		COMPAT_CFLAGS += -D__USE_MINGW_ANSI_STDIO=0 -DDETECT_MSYS_TTY \
>  			-fstack-protector-strong
> +		BASIC_LDFLAGS += -fstack-protector-strong
>  		EXTLIBS += -lntdll
>  		INSTALL = /bin/install
>  		NO_R_TO_GCC_LINKER = YesPlease

This is an example of the problem we discussed earlier for not
passing ALL_CFLAGS to the linking phase.  I am not sure what the
best solution is, though.

Thanks.
diff mbox series

Patch

diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index 30425404eb..5ece32d4fa 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -252,6 +252,7 @@  jobs:
             pool: ubuntu-latest
     env:
       CC: ${{matrix.vector.cc}}
+      LD: ${{matrix.vector.cc}}
       jobname: ${{matrix.vector.jobname}}
     runs-on: ${{matrix.vector.pool}}
     steps:
diff --git a/Makefile b/Makefile
index 86e5411f39..c0c0c280f0 100644
--- a/Makefile
+++ b/Makefile
@@ -543,6 +543,7 @@  export prefix bindir sharedir sysconfdir gitwebdir perllibdir localedir
 
 # Set our default programs
 CC = cc
+LD = cc
 AR = ar
 RM = rm -f
 DIFF = diff
@@ -2121,7 +2122,7 @@  git.sp git.s git.o: EXTRA_CPPFLAGS = \
 	'-DGIT_INFO_PATH="$(infodir_relative_SQ)"'
 
 git$X: git.o GIT-LDFLAGS $(BUILTIN_OBJS) $(GITLIBS)
-	$(QUIET_LINK)$(CC) $(ALL_CFLAGS) -o $@ $(ALL_LDFLAGS) \
+	$(QUIET_LINK)$(LD) -o $@ $(ALL_LDFLAGS) \
 		$(filter %.o,$^) $(LIBS)
 
 help.sp help.s help.o: command-list.h
@@ -2445,17 +2446,17 @@  compat/nedmalloc/nedmalloc.sp: SP_EXTRA_FLAGS += -Wno-non-pointer-null
 endif
 
 git-%$X: %.o GIT-LDFLAGS $(GITLIBS)
-	$(QUIET_LINK)$(CC) $(ALL_CFLAGS) -o $@ $(ALL_LDFLAGS) $(filter %.o,$^) $(LIBS)
+	$(QUIET_LINK)$(LD) -o $@ $(ALL_LDFLAGS) $(filter %.o,$^) $(LIBS)
 
 git-imap-send$X: imap-send.o $(IMAP_SEND_BUILDDEPS) GIT-LDFLAGS $(GITLIBS)
-	$(QUIET_LINK)$(CC) $(ALL_CFLAGS) -o $@ $(ALL_LDFLAGS) $(filter %.o,$^) \
+	$(QUIET_LINK)$(LD) -o $@ $(ALL_LDFLAGS) $(filter %.o,$^) \
 		$(IMAP_SEND_LDFLAGS) $(LIBS)
 
 git-http-fetch$X: http.o http-walker.o http-fetch.o GIT-LDFLAGS $(GITLIBS)
-	$(QUIET_LINK)$(CC) $(ALL_CFLAGS) -o $@ $(ALL_LDFLAGS) $(filter %.o,$^) \
+	$(QUIET_LINK)$(LD) -o $@ $(ALL_LDFLAGS) $(filter %.o,$^) \
 		$(CURL_LIBCURL) $(LIBS)
 git-http-push$X: http.o http-push.o GIT-LDFLAGS $(GITLIBS)
-	$(QUIET_LINK)$(CC) $(ALL_CFLAGS) -o $@ $(ALL_LDFLAGS) $(filter %.o,$^) \
+	$(QUIET_LINK)$(LD) -o $@ $(ALL_LDFLAGS) $(filter %.o,$^) \
 		$(CURL_LIBCURL) $(EXPAT_LIBEXPAT) $(LIBS)
 
 $(REMOTE_CURL_ALIASES): $(REMOTE_CURL_PRIMARY)
@@ -2465,7 +2466,7 @@  $(REMOTE_CURL_ALIASES): $(REMOTE_CURL_PRIMARY)
 	cp $< $@
 
 $(REMOTE_CURL_PRIMARY): remote-curl.o http.o http-walker.o GIT-LDFLAGS $(GITLIBS)
-	$(QUIET_LINK)$(CC) $(ALL_CFLAGS) -o $@ $(ALL_LDFLAGS) $(filter %.o,$^) \
+	$(QUIET_LINK)$(LD) -o $@ $(ALL_LDFLAGS) $(filter %.o,$^) \
 		$(CURL_LIBCURL) $(EXPAT_LIBEXPAT) $(LIBS)
 
 $(LIB_FILE): $(LIB_OBJS)
@@ -2753,7 +2754,7 @@  perf: all
 t/helper/test-tool$X: $(patsubst %,t/helper/%,$(TEST_BUILTINS_OBJS))
 
 t/helper/test-%$X: t/helper/test-%.o GIT-LDFLAGS $(GITLIBS)
-	$(QUIET_LINK)$(CC) $(ALL_CFLAGS) -o $@ $(ALL_LDFLAGS) $(filter %.o,$^) $(filter %.a,$^) $(LIBS)
+	$(QUIET_LINK)$(LD) -o $@ $(ALL_LDFLAGS) $(filter %.o,$^) $(filter %.a,$^) $(LIBS)
 
 check-sha1:: t/helper/test-tool$X
 	t/helper/test-sha1.sh
diff --git a/ci/lib.sh b/ci/lib.sh
index 3eefec500d..19c5beb277 100755
--- a/ci/lib.sh
+++ b/ci/lib.sh
@@ -125,6 +125,7 @@  then
 	test darwin != "$CI_OS_NAME" || CI_OS_NAME=osx
 	CI_REPO_SLUG="$(expr "$BUILD_REPOSITORY_URI" : '.*/\([^/]*/[^/]*\)$')"
 	CC="${CC:-gcc}"
+	LD="$CC"
 
 	# use a subdirectory of the cache dir (because the file share is shared
 	# among *all* phases)
@@ -149,6 +150,7 @@  then
 	CI_REPO_SLUG="$GITHUB_REPOSITORY"
 	CI_JOB_ID="$GITHUB_RUN_ID"
 	CC="${CC:-gcc}"
+	LD="$CC"
 
 	cache_dir="$HOME/none"
 
@@ -184,6 +186,7 @@  linux-clang|linux-gcc)
 	if [ "$jobname" = linux-gcc ]
 	then
 		export CC=gcc-8
+		export LD="$CC"
 		MAKEFLAGS="$MAKEFLAGS PYTHON_PATH=/usr/bin/python3"
 	else
 		MAKEFLAGS="$MAKEFLAGS PYTHON_PATH=/usr/bin/python2"
@@ -207,6 +210,7 @@  osx-clang|osx-gcc)
 	if [ "$jobname" = osx-gcc ]
 	then
 		export CC=gcc-9
+		export LD="$CC"
 		MAKEFLAGS="$MAKEFLAGS PYTHON_PATH=$(which python3)"
 	else
 		MAKEFLAGS="$MAKEFLAGS PYTHON_PATH=$(which python2)"
@@ -222,12 +226,14 @@  GETTEXT_POISON)
 	;;
 Linux32)
 	CC=gcc
+	LD="$CC"
 	;;
 linux-musl)
 	CC=gcc
+	LD="$CC"
 	MAKEFLAGS="$MAKEFLAGS PYTHON_PATH=/usr/bin/python3 USE_LIBPCRE2=Yes"
 	MAKEFLAGS="$MAKEFLAGS NO_REGEX=Yes ICONV_OMITS_BOM=Yes"
 	;;
 esac
 
-MAKEFLAGS="$MAKEFLAGS CC=${CC:-cc}"
+MAKEFLAGS="$MAKEFLAGS CC=${CC:-cc} LD=${LD:-cc}"
diff --git a/config.mak.in b/config.mak.in
index e6a6d0f941..76ea7e781e 100644
--- a/config.mak.in
+++ b/config.mak.in
@@ -2,6 +2,7 @@ 
 # @configure_input@
 
 CC = @CC@
+LD = @CC@
 CFLAGS = @CFLAGS@
 CPPFLAGS = @CPPFLAGS@
 LDFLAGS = @LDFLAGS@
diff --git a/config.mak.uname b/config.mak.uname
index c7eba69e54..886ce068f8 100644
--- a/config.mak.uname
+++ b/config.mak.uname
@@ -69,6 +69,7 @@  ifeq ($(uname_S),GNU/kFreeBSD)
 endif
 ifeq ($(uname_S),UnixWare)
 	CC = cc
+	LD = $(CC)
 	NEEDS_SOCKET = YesPlease
 	NEEDS_NSL = YesPlease
 	NEEDS_SSL_WITH_CRYPTO = YesPlease
@@ -90,6 +91,7 @@  ifeq ($(uname_S),SCO_SV)
 	endif
 	ifeq ($(uname_R),5)
 		CC = cc
+		LD = $(CC)
 		BASIC_CFLAGS += -Kthread
 	endif
 	NEEDS_SOCKET = YesPlease
@@ -435,6 +437,7 @@  ifeq ($(uname_S),Windows)
 	DEFAULT_HELP_FORMAT = html
 
 	CC = compat/vcbuild/scripts/clink.pl
+	LD = $(CC)
 	AR = compat/vcbuild/scripts/lib.pl
 	CFLAGS =
 	BASIC_CFLAGS = -nologo -I. -Icompat/vcbuild/include -DWIN32 -D_CONSOLE -DHAVE_STRING_H -D_CRT_SECURE_NO_WARNINGS -D_CRT_NONSTDC_NO_DEPRECATE
@@ -525,6 +528,7 @@  ifeq ($(uname_S),NONSTOP_KERNEL)
 	ifeq ($(uname_R).$(uname_V),L17.02)
 		CC += -WRVU=L16.05
 	endif
+	LD = $(CC)
 	# Disable all optimization, seems to result in bad code, with -O or -O2
 	# or even -O1 (default), /usr/local/libexec/git-core/git-pack-objects
 	# abends on "git push". Needs more investigation.
@@ -665,8 +669,10 @@  else
 			BASIC_LDFLAGS += -Wl,--large-address-aware
 		endif
 		CC = gcc
+		LD = $(CC)
 		COMPAT_CFLAGS += -D__USE_MINGW_ANSI_STDIO=0 -DDETECT_MSYS_TTY \
 			-fstack-protector-strong
+		BASIC_LDFLAGS += -fstack-protector-strong
 		EXTLIBS += -lntdll
 		INSTALL = /bin/install
 		NO_R_TO_GCC_LINKER = YesPlease