On 12/04/2017 07:20 PM, Paul Lawrence wrote: > > > + # -fasan-shadow-offset fails without -fsanitize > > + CFLAGS_KASAN_SHADOW := $(call cc-option, -fsanitize=kernel-address \ > > + -fasan-shadow-offset=$(KASAN_SHADOW_OFFSET), \ > > + $(call cc-option, -fsanitize=kernel-address \ > > + -mllvm -asan-mapping-offset=$(KASAN_SHADOW_OFFSET))) > > + > > + ifeq ("$(CFLAGS_KASAN_SHADOW)"," ") > > This not how it was in my original patch. Why you changed this? > Condition is always false now, so it breaks kasan with 4.9.x gcc. > > > I had the opposite problem - CFLAGS_KASAN_SHADOW is always at least a space, and the > original condition would always be false, which is why I changed it. On investigation, I found > that if the line was split it would always be a space - $(false,whatever,empty-string) would be > truly empty, but if the line was split after the second comma it would be one space. Is this a > difference in our make systems? I dunno, but it could be. Anyways, does the fixup bellow works for you? --- scripts/Makefile.kasan | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/scripts/Makefile.kasan b/scripts/Makefile.kasan index 7c00be9216f4..d5a1a4b6d079 100644 --- a/scripts/Makefile.kasan +++ b/scripts/Makefile.kasan @@ -24,7 +24,7 @@ else $(call cc-option, -fsanitize=kernel-address \ -mllvm -asan-mapping-offset=$(KASAN_SHADOW_OFFSET))) - ifeq ("$(CFLAGS_KASAN_SHADOW)"," ") + ifeq ($(strip $(CFLAGS_KASAN_SHADOW)),) CFLAGS_KASAN := $(CFLAGS_KASAN_MINIMAL) else # Now add all the compiler specific options that are valid standalone -- 2.13.6 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx"> email@xxxxxxxxx </a>