x86/build: Don't add -maccumulate-outgoing-args w/o compiler support

Clang does not support this machine dependent option.

Older versions of GCC (pre 3.0) may not support this option, added in
2000, but it's unlikely they can still compile a working kernel.

Signed-off-by: Nick Desaulniers <nick.desaulniers@gmail.com>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20170509032946.20444-1-nick.desaulniers@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

diff --git a/arch/x86/Makefile b/arch/x86/Makefile
index 4430dd489620f0ed1f7e35af5ddde0b02356110d..5851411e60fb9fd008f0035ac92932bd03eb519b 100644 (file)
--- a/arch/x86/Makefile
+++ b/arch/x86/Makefile
@@ -179,7 +179,8 @@ ifdef CONFIG_JUMP_LABEL
 endif
 
 ifeq ($(ACCUMULATE_OUTGOING_ARGS), 1)
-       KBUILD_CFLAGS += -maccumulate-outgoing-args
+       # This compiler flag is not supported by Clang:
+       KBUILD_CFLAGS += $(call cc-option,-maccumulate-outgoing-args,)
 endif
 
 # Stackpointer is addressed different for 32 bit and 64 bit x86