Makefile.extrawarn: turn on missing-prototypes globally

Over the years we went from > 1000 of warnings to under 100 earlier this
year, and I sent patches to address all the ones that I saw with compile
testing randcom configs on arm64, arm and x86 kernels.  This is a really
useful warning, as it catches real bugs when there are mismatched
prototypes.  In particular with kernel control flow integrity enabled,
those are no longer allowed.

I have done extensive testing to ensure that there are no new build errors
or warnings on any configuration of x86, arm and arm64 builds.  I also
made sure that at least both the normal defconfig and an allmodconfig
build is clean for arc, csky, loongarch, m68k, microblaze, openrisc,
parisc, powerpc, riscv, s390, and xtensa, with the respective maintainers
doing most of the patches.

At this point, there are five architectures with a number of known
regressions: alpha, nios2, mips, sh and sparc.  In the previous version of
this patch, I had turned off the missing prototype warnings for the 15
architectures that still had issues, but since there are only five left, I
think we can leave the rest to the maintainers (Cc'd here) as well.

Link: https://lkml.kernel.org/r/20231123110506.707903-7-arnd@kernel.org
Link: https://lore.kernel.org/lkml/20230810141947.1236730-1-arnd@kernel.org/
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Palmer Dabbelt <palmer@rivosinc.com> # RISC-V
Cc: Richard Henderson <richard.henderson@linaro.org>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Rich Felker <dalias@libc.org>
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Nicolas Schier <nicolas@fjasle.eu>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Tudor Ambarus <tudor.ambarus@linaro.org>
Cc: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit is contained in:
Arnd Bergmann 2023-11-23 12:05:06 +01:00 committed by Andrew Morton
parent bbe4f634f4
commit 0fcb70851f

View file

@ -17,6 +17,8 @@ KBUILD_CFLAGS += -Wno-format-security
KBUILD_CFLAGS += -Wno-trigraphs
KBUILD_CFLAGS += $(call cc-disable-warning,frame-address,)
KBUILD_CFLAGS += $(call cc-disable-warning, address-of-packed-member)
KBUILD_CFLAGS += -Wmissing-declarations
KBUILD_CFLAGS += -Wmissing-prototypes
ifneq ($(CONFIG_FRAME_WARN),0)
KBUILD_CFLAGS += -Wframe-larger-than=$(CONFIG_FRAME_WARN)
@ -95,10 +97,8 @@ export KBUILD_EXTRA_WARN
ifneq ($(findstring 1, $(KBUILD_EXTRA_WARN)),)
KBUILD_CFLAGS += -Wextra -Wunused -Wno-unused-parameter
KBUILD_CFLAGS += -Wmissing-declarations
KBUILD_CFLAGS += $(call cc-option, -Wrestrict)
KBUILD_CFLAGS += -Wmissing-format-attribute
KBUILD_CFLAGS += -Wmissing-prototypes
KBUILD_CFLAGS += -Wold-style-definition
KBUILD_CFLAGS += -Wmissing-include-dirs
KBUILD_CFLAGS += $(call cc-option, -Wunused-but-set-variable)