Re: [PATCH 5/5] Makefile: disable unaligned loads with UBSan
- From
René Scharfe <l.s.r@web.de>
- Date
- Jul 15, 2017, 17:18 UTC
- Message-ID
- <de9c876c-f018-ad6b-3813-576ea73dd49a@web.de>
- In-Reply-To
- <20170710132450.yxojk5cybejy7und@sigill.intra.peff.net>
Am 10.07.2017 um 15:24 schrieb Jeff King:
Show 28 quoted lines
> The undefined behavior sanitizer complains about unaligned > loads, even if they're OK for a particular platform in > practice. It's possible that they _are_ a problem, of > course, but since it's a known tradeoff the UBSan errors are > just noise. > > Let's quiet it automatically by building with > NO_UNALIGNED_LOADS when SANITIZE=undefined is in use. > > Signed-off-by: Jeff King <peff@peff.net> > --- > Makefile | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/Makefile b/Makefile > index cc03b3c95..3c341b2a6 100644 > --- a/Makefile > +++ b/Makefile > @@ -1015,6 +1015,9 @@ endif > ifdef SANITIZE > BASIC_CFLAGS += -fsanitize=$(SANITIZE) -fno-sanitize-recover=$(SANITIZE) > BASIC_CFLAGS += -fno-omit-frame-pointer > +ifeq ($(SANITIZE),undefined) > +BASIC_CFLAGS += -DNO_UNALIGNED_LOADS > +endif > endif > > ifndef sysconfdir
Nice, but let's be even nicer!
-- >8 -- Subject: [PATCH] Makefile: allow combining UBSan with other sanitizers
Multiple sanitizers can be specified as a comma-separated list. Set the flag NO_UNALIGNED_LOADS even if UndefinedBehaviorSanitizer is not the only sanitizer to build with.
Signed-off-by: Rene Scharfe <l.s.r@web.de> --- Makefile | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/Makefile b/Makefile index ba4359ef8d..9b98535a04 100644 --- a/Makefile +++ b/Makefile @@ -1022,10 +1022,15 @@ ifdef DEVELOPER CFLAGS += $(DEVELOPER_CFLAGS) endif +comma := , +empty := +space := $(empty) $(empty) + ifdef SANITIZE +SANITIZERS := $(foreach flag,$(subst $(comma),$(space),$(SANITIZE)),$(flag)) BASIC_CFLAGS += -fsanitize=$(SANITIZE) -fno-sanitize-recover=$(SANITIZE) BASIC_CFLAGS += -fno-omit-frame-pointer -ifeq ($(SANITIZE),undefined) +ifneq ($(filter undefined,$(SANITIZERS)),) BASIC_CFLAGS += -DNO_UNALIGNED_LOADS endif endif
-- 2.13.3