From: Josh Poimboeuf <jpoimboe@xxxxxxxxxx> commit f73b3cc39c84220e6dccd463b5c8279b03514646 upstream. If the build user has the CFLAGS variable set in their environment, objtool blindly appends to it, which can cause unexpected behavior. Clobber CFLAGS to ensure consistent objtool compilation behavior. Reported-by: Valdis Kletnieks <valdis.kletnieks@xxxxxx> Tested-by: Valdis Kletnieks <valdis.kletnieks@xxxxxx> Signed-off-by: Josh Poimboeuf <jpoimboe@xxxxxxxxxx> Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Link: https://lkml.kernel.org/r/83a276df209962e6058fcb6c615eef9d401c21bc.1567121311.git.jpoimboe@xxxxxxxxxx Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx> CC: Nathan Chancellor <natechancellor@xxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- tools/objtool/Makefile | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/tools/objtool/Makefile +++ b/tools/objtool/Makefile @@ -35,7 +35,7 @@ INCLUDES := -I$(srctree)/tools/include \ -I$(srctree)/tools/arch/$(HOSTARCH)/include/uapi \ -I$(srctree)/tools/objtool/arch/$(ARCH)/include WARNINGS := $(EXTRA_WARNINGS) -Wno-switch-default -Wno-switch-enum -Wno-packed -CFLAGS += -Werror $(WARNINGS) $(KBUILD_HOSTCFLAGS) -g $(INCLUDES) $(LIBELF_FLAGS) +CFLAGS := -Werror $(WARNINGS) $(KBUILD_HOSTCFLAGS) -g $(INCLUDES) $(LIBELF_FLAGS) LDFLAGS += $(LIBELF_LIBS) $(LIBSUBCMD) $(KBUILD_HOSTLDFLAGS) # Allow old libelf to be used:
