as-instr uses KBUILD_AFLAGS, but as-option uses KBUILD_CFLAGS. This can cause as-option to fail unexpectedly when CONFIG_WERROR is set, because clang will emit -Werror,-Wunused-command-line-argument for various -m and -f flags for assembler sources. Callers of as-option (and as-instr) likely want to be adding flags to KBUILD_AFLAGS/aflags-y, not KBUILD_CFLAGS/cflags-y. Also, change as-option and as-instr to use -x assembler-with-cpp since kernel sources are .S files that use the compiler as the driver. And then add -Werror as well. Link: https://github.com/ClangBuiltLinux/linux/issues/1699 Suggested-by: Masahiro Yamada <masahiroy@xxxxxxxxxx> Reviewed-by: Nathan Chancellor <nathan@xxxxxxxxxx> Signed-off-by: Nick Desaulniers <ndesaulniers@xxxxxxxxxx> --- Changes v2 -> v1: * Add -x assembler-with-cpp -Werror to both as-option and (new) as-instr, as per Masahiro. * Add Masahiro's SB tag. Changes v1 -> v2: * Split off changes to arch/x86/boot/compressed/Makefile into parent patch, as per Masahiro. scripts/Makefile.compiler | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/scripts/Makefile.compiler b/scripts/Makefile.compiler index 94d0d40cddb3..a66638b5f4a5 100644 --- a/scripts/Makefile.compiler +++ b/scripts/Makefile.compiler @@ -29,16 +29,16 @@ try-run = $(shell set -e; \ fi) # as-option -# Usage: cflags-y += $(call as-option,-Wa$(comma)-isa=foo,) +# Usage: aflags-y += $(call as-option,-Wa$(comma)-isa=foo,) as-option = $(call try-run,\ - $(CC) $(KBUILD_CFLAGS) $(1) -c -x assembler /dev/null -o "$$TMP",$(1),$(2)) + $(CC) -Werror $(KBUILD_AFLAGS) $(1) -c -x assembler-with-cpp /dev/null -o "$$TMP",$(1),$(2)) # as-instr -# Usage: cflags-y += $(call as-instr,instr,option1,option2) +# Usage: aflags-y += $(call as-instr,instr,option1,option2) as-instr = $(call try-run,\ - printf "%b\n" "$(1)" | $(CC) $(KBUILD_AFLAGS) -c -x assembler -o "$$TMP" -,$(2),$(3)) + printf "%b\n" "$(1)" | $(CC) -Werror $(KBUILD_AFLAGS) -c -x assembler-with-cpp -o "$$TMP" -,$(2),$(3)) # __cc-option # Usage: MY_CFLAGS += $(call __cc-option,$(CC),$(MY_CFLAGS),-march=winchip-c6,-march=i586) -- 2.37.2.789.g6183377224-goog
