[PATCH v2 1/6] ubsan: Use Clang's -fsanitize-trap=undefined option

[Kees Cook <keescook@chromium.org>]

Clang changed the way it enables UBSan trapping mode. Update the Makefile
logic to discover it.

Suggested-by: Fangrui Song <maskray@google.com>
Link: https://lore.kernel.org/lkml/CAFP8O3JivZh+AAV7N90Nk7U2BHRNST6MRP0zHtfQ-Vj0m4+pDA@mail.gmail.com/
Reviewed-by: Fangrui Song <maskray@google.com>
Reviewed-by: Justin Stitt <justinstitt@google.com>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Nicolas Schier <nicolas@fjasle.eu>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Bill Wendling <morbo@google.com>
Cc: linux-kbuild@vger.kernel.org
Cc: llvm@lists.linux.dev
Signed-off-by: Kees Cook <keescook@chromium.org>
---
 scripts/Makefile.ubsan | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/scripts/Makefile.ubsan b/scripts/Makefile.ubsan
index 4749865c1b2c..7cf42231042b 100644
--- a/scripts/Makefile.ubsan
+++ b/scripts/Makefile.ubsan
@@ -10,6 +10,6 @@ ubsan-cflags-$(CONFIG_UBSAN_DIV_ZERO)		+= -fsanitize=integer-divide-by-zero
 ubsan-cflags-$(CONFIG_UBSAN_UNREACHABLE)	+= -fsanitize=unreachable
 ubsan-cflags-$(CONFIG_UBSAN_BOOL)		+= -fsanitize=bool
 ubsan-cflags-$(CONFIG_UBSAN_ENUM)		+= -fsanitize=enum
-ubsan-cflags-$(CONFIG_UBSAN_TRAP)		+= -fsanitize-undefined-trap-on-error
+ubsan-cflags-$(CONFIG_UBSAN_TRAP)		+= $(call cc-option,-fsanitize-trap=undefined,-fsanitize-undefined-trap-on-error)
 
 export CFLAGS_UBSAN := $(ubsan-cflags-y)
-- 
2.34.1