[kbuild-all] [PATCH] compiler_attributes.h: Support no_sanitize_undefined check with GCC 4

UBSAN is supported since GCC 4.9, which unfortunately did not yet have __has_attribute(). To work around, the __GCC4_has_attribute workaround requires defining which compiler version supports the given attribute. In the case of no_sanitize_undefined, it is the first version that supports UBSAN, which is GCC 4.9. Reported-by: kernel test robot <lkp(a)intel.com&gt; Signed-off-by: Marco Elver <elver(a)google.com&gt; --- Doing a 'make W=1' with GCC 4.9 and the provided config fixes the build robot's report. Peter: Feel free to either squash this patch into the one adding __no_sanitize_undefined or apply on top. Although at this point we don't have any users of __no_sanitize_undefined anymore since objtool resolved the noinstr problem for UBSAN differently. We should probably keep the attribute around because eventually somebody will need it. Thanks, -- Marco --- include/linux/compiler_attributes.h | 1 + 1 file changed, 1 insertion(+) diff --git a/include/linux/compiler_attributes.h b/include/linux/compiler_attributes.h index cdf016596659..c8f03d2969df 100644 --- a/include/linux/compiler_attributes.h +++ b/include/linux/compiler_attributes.h @@ -40,6 +40,7 @@ # define __GCC4_has_attribute___noclone__ 1 # define __GCC4_has_attribute___nonstring__ 0 # define __GCC4_has_attribute___no_sanitize_address__ (__GNUC_MINOR__ >= 8) +# define __GCC4_has_attribute___no_sanitize_undefined__ (__GNUC_MINOR__ >= 9) # define __GCC4_has_attribute___fallthrough__ 0 #endif -- 2.27.0.290.gba653c62da-goog