ubsan: fix tree-wide -Wmaybe-uninitialized false positives (dde5cf39) · Commits · 戴 / test

-fsanitize=* options makes GCC less smart than usual and increase number of 'maybe-uninitialized' false-positives. So this patch does two things: * Add -Wno-maybe-uninitialized to CFLAGS_UBSAN which will disable all such warnings for instrumented files. * Remove CONFIG_UBSAN_SANITIZE_ALL from all[yes|mod]config builds. So the all[yes|mod]config build goes without -fsanitize=* and still with -Wmaybe-uninitialized. Signed-off-by:

Andrey Ryabinin <aryabinin@virtuozzo.com> Reported-by:

Fengguang Wu <fengguang.wu@intel.com> Signed-off-by:

Andrew Morton <akpm@linux-foundation.org> Signed-off-by:

Linus Torvalds <torvalds@linux-foundation.org>

lib/Kconfig.ubsan

+5 −0

Original line number	Diff line number	Diff line
		@@ -13,6 +13,11 @@ config UBSAN_SANITIZE_ALL
		bool "Enable instrumentation for the entire kernel"
		depends on UBSAN
		depends on ARCH_HAS_UBSAN_SANITIZE_ALL

		# We build with -Wno-maybe-uninitilzed, but we still want to
		# use -Wmaybe-uninitilized in allmodconfig builds.
		# So dependsy bellow used to disable this option in allmodconfig
		depends on !COMPILE_TEST
		default y
		help
		This option activates instrumentation for the entire kernel.

scripts/Makefile.ubsan

+4 −0

Original line number	Diff line number	Diff line
		@@ -14,4 +14,8 @@ ifdef CONFIG_UBSAN
		ifdef CONFIG_UBSAN_ALIGNMENT
		CFLAGS_UBSAN += $(call cc-option, -fsanitize=alignment)
		endif

		# -fsanitize=* options makes GCC less smart than usual and
		# increase number of 'maybe-uninitialized false-positives
		CFLAGS_UBSAN += $(call cc-option, -Wno-maybe-uninitialized)
		endif

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