@@ -659,6 +660,12 @@ KBUILD_CFLAGS += $(call cc-option,-fno-strict-overflow)
# conserve stack if available
KBUILD_CFLAGS += $(call cc-option,-fconserve-stack)
+# disallog errors like 'EXPORT_GPL(foo);' with missing header
+KBUILD_CFLAGS += $(call cc-option,-Werror=implicit-int)
+
+# require functions to have argumens in prototypes, not empty 'int foo()'
+KBUILD_CFLAGS += $(call cc-option,-Werror=strict-prototypes)
+
# use the deterministic mode of AR if available
KBUILD_ARFLAGS := $(call ar-option,D)
The common error fount in forward-ported/backported patches is missing headers. One recent example (files and function names are mangled): void foo(){} EXPORT_SYMBOL(foo); gave only warning foo.c:12345678:5: warning: function declaration isn't a prototype [-Wstrict-prototypes] void foo(){} ^ foo.c:12345679:5: warning: data definition has no type or storage class [enabled by default] EXPORT_SYMBOL(foo); foo.c:12345679:5: warning: type defaults to 'int' in declaration of 'EXORT_SYMBOL' [-Werror=implicit-int] Now it's a fatal error. Tested on x86_64 allyesconfig. Signed-off-by: Sergei Trofimovich <slyfox@gentoo.org> Cc: Michal Marek <mmarek@suse.cz> Cc: linux-kbuild@vger.kernel.org Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Geert Uytterhoeven <geert@linux-m68k.org> --- Makefile | 6 +++++++ 1 file changed, 6 insertions(+) Change since v2: - moved CFLAGS checks lower to catch $(CROSS) case as suggested by Geert - added comments as other warning options do Change since v1: - use 'cc-option' to respect old gccs - fix typos. Thanks to Oleg Verych