| Message ID | 20250221212017.809382-1-arnd@kernel.org (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | kbuild: hdrcheck: fix cross build with clang | expand |
On Fri, Feb 21, 2025 at 10:20:07PM +0100, Arnd Bergmann wrote: > From: Arnd Bergmann <arnd@arndb.de> > > The headercheck tries to call clang with a mix of compiler arguments > that don't include the target architecture. When building e.g. x86 > headers on arm64, this produces a warning like > > clang: warning: unknown platform, assuming -mfloat-abi=soft > > Add in the CLANG_FLAGS, which contain the target, in order to make it > build properly. > > Signed-off-by: Arnd Bergmann <arnd@arndb.de> This looks like a similar problem as the one fixed by commit 1b71c2fb04e7 ("kbuild: userprogs: fix bitsize and target detection on clang"), should it be addressed in the same manner (especially since I think the Fixes commit would be the same)? Given that the filter expression is the same, maybe it would be possible to unify them but that could happen as a follow up. > --- > usr/include/Makefile | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/usr/include/Makefile b/usr/include/Makefile > index 58a9cbe4eba4..99f9e904adcd 100644 > --- a/usr/include/Makefile > +++ b/usr/include/Makefile > @@ -10,7 +10,7 @@ UAPI_CFLAGS := -std=c90 -Wall -Werror=implicit-function-declaration > > # In theory, we do not care -m32 or -m64 for header compile tests. > # It is here just because CONFIG_CC_CAN_LINK is tested with -m32 or -m64. > -UAPI_CFLAGS += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS)) > +UAPI_CFLAGS += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS) $(CLANG_FLAGS)) > > # USERCFLAGS might contain sysroot location for CC. > UAPI_CFLAGS += $(USERCFLAGS) > -- > 2.39.5 >
On Fri, Feb 21, 2025, at 22:26, Nathan Chancellor wrote: > On Fri, Feb 21, 2025 at 10:20:07PM +0100, Arnd Bergmann wrote: >> From: Arnd Bergmann <arnd@arndb.de> >> >> The headercheck tries to call clang with a mix of compiler arguments >> that don't include the target architecture. When building e.g. x86 >> headers on arm64, this produces a warning like >> >> clang: warning: unknown platform, assuming -mfloat-abi=soft >> >> Add in the CLANG_FLAGS, which contain the target, in order to make it >> build properly. >> >> Signed-off-by: Arnd Bergmann <arnd@arndb.de> > > This looks like a similar problem as the one fixed by > commit 1b71c2fb04e7 ("kbuild: userprogs: fix bitsize and target > detection on clang"), should it be addressed in the same manner > (especially since I think the Fixes commit would be the same)? Given > that the filter expression is the same, maybe it would be possible to > unify them but that could happen as a follow up. My bad, I actually had an old patch that addressed both issues and then dropped it when the Thomas' patch made it into linux-next but ended up picking my old change for usr/include/Makefile instead of trying to understand the difference. I'll send a v2 after some more build testing. Arnd
diff --git a/usr/include/Makefile b/usr/include/Makefile index 58a9cbe4eba4..99f9e904adcd 100644 --- a/usr/include/Makefile +++ b/usr/include/Makefile @@ -10,7 +10,7 @@ UAPI_CFLAGS := -std=c90 -Wall -Werror=implicit-function-declaration # In theory, we do not care -m32 or -m64 for header compile tests. # It is here just because CONFIG_CC_CAN_LINK is tested with -m32 or -m64. -UAPI_CFLAGS += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS)) +UAPI_CFLAGS += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS) $(CLANG_FLAGS)) # USERCFLAGS might contain sysroot location for CC. UAPI_CFLAGS += $(USERCFLAGS)