next-20160314 - KASAN breaks 'make C=2' build...

From: Valdis Kletnieks
Date: Tue Mar 15 2016 - 05:11:47 EST


This config breaks sparse:

grep KASAN .config
CONFIG_KASAN_SHADOW_OFFSET=0xdffffc0000000000
CONFIG_HAVE_ARCH_KASAN=y
CONFIG_KASAN=y
# CONFIG_KASAN_OUTLINE is not set
CONFIG_KASAN_INLINE=y
CONFIG_TEST_KASAN=m

LANG=C make C=2
CHK include/config/kernel.release
CHK include/generated/uapi/linux/version.h
CHK include/generated/utsrelease.h
CHK include/generated/bounds.h
CHK include/generated/timeconst.h
CHK include/generated/asm-offsets.h
CALL scripts/checksyscalls.sh
DESCEND objtool
CHECK scripts/mod/empty.c
No such file: asan-stack=1
scripts/Makefile.build:291: recipe for target 'scripts/mod/empty.o' failed
make[2]: *** [scripts/mod/empty.o] Error 1
scripts/Makefile.build:440: recipe for target 'scripts/mod' failed
make[1]: *** [scripts/mod] Error 2
Makefile:552: recipe for target 'scripts' failed
make: *** [scripts] Error 2

Looks like it's this chunk from scripts/Makefile.kasan:

CFLAGS_KASAN := $(call cc-option, -fsanitize=kernel-address
-fasan-shadow-offset=$(KASAN_SHADOW_OFFSET)
--param asan-stack=1 --param asan-globals=1
--param asan-instrumentation-with-call-threshold=$(call_threshold))

4AM is a bad time to figure out who's to blame here....