From fe026a851b6bb9a11c27e93b9b15060cb310a3d6 Mon Sep 17 00:00:00 2001 From: Nicholas Piggin Date: Thu, 24 Nov 2016 03:41:38 +1100 Subject: kbuild: thin archives for multi-y targets THIN_ARCHIVES builds archives for built-in.o targets, have it build multi-y targets as archives as well. This saves another ~15% of the size of intermediate artifacts in the build tree. After this patch, the linker is only used in final link, and special cases like vdsos. Signed-off-by: Nicholas Piggin Signed-off-by: Michal Marek --- scripts/Makefile.build | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-) (limited to 'scripts/Makefile.build') diff --git a/scripts/Makefile.build b/scripts/Makefile.build index de46ab03f063..9807a8115896 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -448,11 +448,18 @@ $($(subst $(obj)/,,$(@:.o=-objs))) \ $($(subst $(obj)/,,$(@:.o=-y))) \ $($(subst $(obj)/,,$(@:.o=-m)))), $^) -quiet_cmd_link_multi-y = LD $@ -cmd_link_multi-y = $(LD) $(ld_flags) -r -o $@ $(link_multi_deps) $(cmd_secanalysis) +cmd_link_multi-link = $(LD) $(ld_flags) -r -o $@ $(link_multi_deps) $(cmd_secanalysis) + +ifdef CONFIG_THIN_ARCHIVES + quiet_cmd_link_multi-y = AR $@ + cmd_link_multi-y = rm -f $@; $(AR) rcST$(KBUILD_ARFLAGS) $@ $(link_multi_deps) +else + quiet_cmd_link_multi-y = LD $@ + cmd_link_multi-y = $(cmd_link_multi-link) +endif quiet_cmd_link_multi-m = LD [M] $@ -cmd_link_multi-m = $(cmd_link_multi-y) +cmd_link_multi-m = $(cmd_link_multi-link) $(multi-used-y): FORCE $(call if_changed,link_multi-y) -- cgit v1.2.3 From 9da2f584b54fa4bf0df4db220cd89b6c7e691c6e Mon Sep 17 00:00:00 2001 From: Nicholas Piggin Date: Thu, 24 Nov 2016 03:41:40 +1100 Subject: kbuild: improve linker compatibility with lib-ksyms.o build lib-ksyms.o is created by linking an empty input file with a linker script containing the interesting bits. Currently the empty input file is an archive containing nothing, however this causes the gold linker to segfault. I have opened a bug against gold https://sourceware.org/bugzilla/show_bug.cgi?id=20767 However this can be worked around by assembling an empty file to link with instead. The resulting lib-ksyms.o is slightly larger (seemingly due to empty .text, .data, .bss setions added), but final linked output should not be changed. Reported-by: Anton Blanchard Signed-off-by: Nicholas Piggin Signed-off-by: Michal Marek --- scripts/Makefile.build | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'scripts/Makefile.build') diff --git a/scripts/Makefile.build b/scripts/Makefile.build index 9807a8115896..fb6a5ee1edec 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -424,7 +424,7 @@ quiet_cmd_export_list = EXPORTS $@ cmd_export_list = $(OBJDUMP) -h $< | \ sed -ne '/___ksymtab/{s/.*+/$(ref_prefix)/;s/ .*/)/;p}' >$(ksyms-lds);\ rm -f $(dummy-object);\ - $(AR) rcs$(KBUILD_ARFLAGS) $(dummy-object);\ + echo | $(CC) $(a_flags) -c -o $(dummy-object) -x assembler -;\ $(LD) $(ld_flags) -r -o $@ -T $(ksyms-lds) $(dummy-object);\ rm $(dummy-object) $(ksyms-lds) -- cgit v1.2.3 From 76bee23411f8510fbf5fc5641bae2c203b726eb6 Mon Sep 17 00:00:00 2001 From: Nicolas Pitre Date: Wed, 16 Nov 2016 19:28:39 -0500 Subject: kbuild: cmd_export_list: tighten the sed script When LTO is used, some ___ksymtab_string sections are seen by this sed script, creating lines containing a single ) such as: EXPORT(foo) ) ) EXPORT(bar) Let's make it so the + character is also required for any line to be printed. Signed-off-by: Nicolas Pitre Signed-off-by: Michal Marek --- scripts/Makefile.build | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'scripts/Makefile.build') diff --git a/scripts/Makefile.build b/scripts/Makefile.build index fb6a5ee1edec..9257a06ffd4e 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -422,7 +422,7 @@ endif quiet_cmd_export_list = EXPORTS $@ cmd_export_list = $(OBJDUMP) -h $< | \ - sed -ne '/___ksymtab/{s/.*+/$(ref_prefix)/;s/ .*/)/;p}' >$(ksyms-lds);\ + sed -ne '/___ksymtab/s/.*+\([^ ]*\).*/$(ref_prefix)\1)/p' >$(ksyms-lds);\ rm -f $(dummy-object);\ echo | $(CC) $(a_flags) -c -o $(dummy-object) -x assembler -;\ $(LD) $(ld_flags) -r -o $@ -T $(ksyms-lds) $(dummy-object);\ -- cgit v1.2.3