From 0fcb70851fbfea1776ae62f67c503fef8f0292b9 Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Thu, 23 Nov 2023 12:05:06 +0100 Subject: [PATCH] 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 Reviewed-by: Kees Cook Acked-by: Palmer Dabbelt # RISC-V Cc: Richard Henderson Cc: Ivan Kokshaysky Cc: Matt Turner Cc: Dinh Nguyen Cc: Thomas Bogendoerfer Cc: Yoshinori Sato Cc: Rich Felker Cc: John Paul Adrian Glaubitz Cc: "David S. Miller" Cc: David Woodhouse Cc: Greg Kroah-Hartman Cc: Masahiro Yamada Cc: Michael Ellerman Cc: Nathan Chancellor Cc: Nicolas Schier Cc: Peter Zijlstra Cc: Richard Weinberger Cc: Stephen Rothwell Cc: Tudor Ambarus Cc: Zhihao Cheng Signed-off-by: Andrew Morton --- scripts/Makefile.extrawarn | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/scripts/Makefile.extrawarn b/scripts/Makefile.extrawarn index 2fe6f2828d37..c9725685aa76 100644 --- a/scripts/Makefile.extrawarn +++ b/scripts/Makefile.extrawarn @@ -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)