4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Mark Charlebois <charlebm@xxxxxxxxx> commit c3f0d0bc5b01ad90c45276952802455750444b4f upstream. Clang will warn about unknown warnings but will not return false unless -Werror is set. GCC will return false if an unknown warning is passed. Adding -Werror make both compiler behave the same. [arnd: it turns out we need the same patch for testing whether -ffunction-sections works right with gcc. I've build tested extensively with this patch applied, so let's just merge this one now.] Signed-off-by: Mark Charlebois <charlebm@xxxxxxxxx> Signed-off-by: Behan Webster <behanw@xxxxxxxxxxxxxxxxxx> Reviewed-by: Jan-Simon Möller <dl9pf@xxxxxx> Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx> Acked-by: Kees Cook <keescook@xxxxxxxxxxxx> Signed-off-by: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx> [nc: Adjust context due to lack of d26e94149276f] Signed-off-by: Nathan Chancellor <natechancellor@xxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- scripts/Kbuild.include | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) --- a/scripts/Kbuild.include +++ b/scripts/Kbuild.include @@ -112,12 +112,12 @@ as-instr = $(call try-run,\ # Usage: cflags-y += $(call cc-option,-march=winchip-c6,-march=i586) cc-option = $(call try-run,\ - $(CC) $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) $(1) -c -x c /dev/null -o "$$TMP",$(1),$(2)) + $(CC) -Werror $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) $(1) -c -x c /dev/null -o "$$TMP",$(1),$(2)) # cc-option-yn # Usage: flag := $(call cc-option-yn,-march=winchip-c6) cc-option-yn = $(call try-run,\ - $(CC) $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) $(1) -c -x c /dev/null -o "$$TMP",y,n) + $(CC) -Werror $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) $(1) -c -x c /dev/null -o "$$TMP",y,n) # cc-option-align # Prefix align with either -falign or -malign @@ -127,7 +127,7 @@ cc-option-align = $(subst -functions=0,, # cc-disable-warning # Usage: cflags-y += $(call cc-disable-warning,unused-but-set-variable) cc-disable-warning = $(call try-run,\ - $(CC) $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) -W$(strip $(1)) -c -x c /dev/null -o "$$TMP",-Wno-$(strip $(1))) + $(CC) -Werror $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) -W$(strip $(1)) -c -x c /dev/null -o "$$TMP",-Wno-$(strip $(1))) # cc-name # Expands to either gcc or clang