On Thu, Oct 13, 2022 at 03:01:17AM +0900, Masahiro Yamada wrote: > CONFIG_WERROR turns warnings into errors, which happens only for *.c > files because -Werror is added to KBUILD_CFLAGS. > > Adding it to KBUILD_CPPFLAGS makes more sense because preprocessors > understand the -Werror option. > > For example, you can put a #warning directive in any preprocessed code. > > warning: #warning "this is a warning message" [-Wcpp] > > If -Werror is added, it is promoted to an error. > > error: #warning "this is a warning message" [-Werror=cpp] > > This commit moves -Werror to KBUILD_CPPFLAGS so it works in the same way > for *.c, *.S, *.lds.S or whatever needs preprocessing. > > Signed-off-by: Masahiro Yamada <masahiroy@xxxxxxxxxx> > Reviewed-by: Nick Desaulniers <ndesaulniers@xxxxxxxxxx> > --- > > (no changes since v1) > > Makefile | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/Makefile b/Makefile > index 85a63a1d29b3..790760d26ea0 100644 > --- a/Makefile > +++ b/Makefile > @@ -859,7 +859,8 @@ stackp-flags-$(CONFIG_STACKPROTECTOR_STRONG) := -fstack-protector-strong > > KBUILD_CFLAGS += $(stackp-flags-y) > > -KBUILD_CFLAGS-$(CONFIG_WERROR) += -Werror > +KBUILD_CPPFLAGS-$(CONFIG_WERROR) += -Werror > +KBUILD_CPPFLAGS += $(KBUILD_CPPFLAGS-y) > KBUILD_CFLAGS-$(CONFIG_CC_NO_ARRAY_BOUNDS) += -Wno-array-bounds > > KBUILD_RUSTFLAGS-$(CONFIG_WERROR) += -Dwarnings > -- > 2.34.1 > > For what it's worth, this is going to break 32-bit ARM builds with clang plus the integrated assembler due to https://github.com/ClangBuiltLinux/linux/issues/1315: clang-16: error: argument unused during compilation: '-march=armv7-a' [-Werror,-Wunused-command-line-argument] Ultimately, I want -Wunused-command-line-argument to be an error anyways (https://github.com/ClangBuiltLinux/linux/issues/1587) but it would be nice to get these cleaned up before this goes in. Cheers, Nathan
