Certain assembler instruction tests may only induce warnings from the assembler on an unsupported instruction or option, which causes as-instr to succeed when it was expected to fail. Some tests workaround this limitation by additionally testing that invalid input fails as expected. However, this is fragile if the assembler is changed to accept the invalid input, as it will cause the instruction/option to be unavailable like it was unsupported even when it is. Use '-Wa,--fatal-warnings' in the as-instr macro to turn these warnings into hard errors, which avoids this fragility and makes tests more robust and well formed. Cc: stable@xxxxxxxxxxxxxxx Suggested-by: Eric Biggers <ebiggers@xxxxxxxxxx> Signed-off-by: Nathan Chancellor <nathan@xxxxxxxxxx> --- scripts/Kconfig.include | 2 +- scripts/Makefile.compiler | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/scripts/Kconfig.include b/scripts/Kconfig.include index 5a84b6443875..3ee8ecfb8c04 100644 --- a/scripts/Kconfig.include +++ b/scripts/Kconfig.include @@ -33,7 +33,7 @@ ld-option = $(success,$(LD) -v $(1)) # $(as-instr,<instr>) # Return y if the assembler supports <instr>, n otherwise -as-instr = $(success,printf "%b\n" "$(1)" | $(CC) $(CLANG_FLAGS) -c -x assembler-with-cpp -o /dev/null -) +as-instr = $(success,printf "%b\n" "$(1)" | $(CC) $(CLANG_FLAGS) -Wa$(comma)--fatal-warnings -c -x assembler-with-cpp -o /dev/null -) # check if $(CC) and $(LD) exist $(error-if,$(failure,command -v $(CC)),C compiler '$(CC)' not found) diff --git a/scripts/Makefile.compiler b/scripts/Makefile.compiler index 8fcb427405a6..92be0c9a13ee 100644 --- a/scripts/Makefile.compiler +++ b/scripts/Makefile.compiler @@ -38,7 +38,7 @@ as-option = $(call try-run,\ # Usage: aflags-y += $(call as-instr,instr,option1,option2) as-instr = $(call try-run,\ - printf "%b\n" "$(1)" | $(CC) -Werror $(CLANG_FLAGS) $(KBUILD_AFLAGS) -c -x assembler-with-cpp -o "$$TMP" -,$(2),$(3)) + printf "%b\n" "$(1)" | $(CC) -Werror $(CLANG_FLAGS) $(KBUILD_AFLAGS) -Wa$(comma)--fatal-warnings -c -x assembler-with-cpp -o "$$TMP" -,$(2),$(3)) # __cc-option # Usage: MY_CFLAGS += $(call __cc-option,$(CC),$(MY_CFLAGS),-march=winchip-c6,-march=i586) -- 2.43.0
