Some old GCC versions between 4.5.0 and 4.9.1 might miscompile code with -fvar-tracking-assingments (which is enabled by default with -g -O2). commit 2062afb4f added -fno-var-tracking-assignments unconditionally to work around this. But newer versions of GCC no longer have this bug, so only add it for versions of GCC before 5.0. Signed-off-by: Mark Wielaard <mark@xxxxxxxxx> Acked-by: Ian Rogers <irogers@xxxxxxxxxx> Cc: linux-toolchains@xxxxxxxxxxxxxxx Cc: Andi Kleen <andi@xxxxxxxxxxxxxx> Cc: Nick Desaulniers <ndesaulniers@xxxxxxxxxx> Cc: Segher Boessenkool <segher@xxxxxxxxxxxxxxxxxxx> Cc: Florian Weimer <fw@xxxxxxxxxxxxx> --- Makefile | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/Makefile b/Makefile index 51540b291738..8477fee5f309 100644 --- a/Makefile +++ b/Makefile @@ -813,7 +813,9 @@ KBUILD_CFLAGS += -ftrivial-auto-var-init=zero KBUILD_CFLAGS += -enable-trivial-auto-var-init-zero-knowing-it-will-be-removed-from-clang endif -DEBUG_CFLAGS := $(call cc-option, -fno-var-tracking-assignments) +# Workaround https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61801 +# for old versions of GCC. +DEBUG_CFLAGS := $(call cc-ifversion, -lt, 0500, $(call cc-option, -fno-var-tracking-assignments)) ifdef CONFIG_DEBUG_INFO ifdef CONFIG_DEBUG_INFO_SPLIT -- 2.18.4
