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| author | Nathan Chancellor <nathan@kernel.org> | 2023-01-12 04:05:05 +0100 |
|---|---|---|
| committer | Masahiro Yamada <masahiroy@kernel.org> | 2023-01-26 04:42:40 +0100 |
| commit | 05e05bfc92d196669a3d087fc34d3998b6ddb758 (patch) | |
| tree | e20642880e48ca05cbc411e23eb780e494aa90ee /arch/powerpc | |
| parent | powerpc/vdso: Improve linker flags (diff) | |
| download | linux-05e05bfc92d196669a3d087fc34d3998b6ddb758.tar.xz linux-05e05bfc92d196669a3d087fc34d3998b6ddb758.zip | |
powerpc/vdso: Remove an unsupported flag from vgettimeofday-32.o with clang
When clang's -Qunused-arguments is dropped from KBUILD_CPPFLAGS, it
warns:
clang-16: error: argument unused during compilation: '-fno-stack-clash-protection' [-Werror,-Wunused-command-line-argument]
This warning happens because vgettimeofday-32.c gets its base CFLAGS
from the main kernel, which may contain flags that are only supported on
a 64-bit target but not a 32-bit one, which is the case here.
-fstack-clash-protection and its negation are only suppported by the
64-bit powerpc target but that flag is included in an invocation for a
32-bit powerpc target, so clang points out that while the flag is one
that it recognizes, it is not actually used by this compiler job.
To eliminate the warning, remove -fno-stack-clash-protection from
vgettimeofday-32.c's CFLAGS when using clang, as has been done for other
flags previously.
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Tested-by: Linux Kernel Functional Testing <lkft@linaro.org>
Tested-by: Anders Roxell <anders.roxell@linaro.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Diffstat (limited to 'arch/powerpc')
| -rw-r--r-- | arch/powerpc/kernel/vdso/Makefile | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/vdso/Makefile b/arch/powerpc/kernel/vdso/Makefile index d4023bceec34..7e69e87fbf74 100644 --- a/arch/powerpc/kernel/vdso/Makefile +++ b/arch/powerpc/kernel/vdso/Makefile @@ -16,6 +16,11 @@ ifneq ($(c-gettimeofday-y),) CFLAGS_vgettimeofday-32.o += -ffreestanding -fasynchronous-unwind-tables CFLAGS_REMOVE_vgettimeofday-32.o = $(CC_FLAGS_FTRACE) CFLAGS_REMOVE_vgettimeofday-32.o += -mcmodel=medium -mabi=elfv1 -mabi=elfv2 -mcall-aixdesc + # This flag is supported by clang for 64-bit but not 32-bit so it will cause + # an unused command line flag warning for this file. + ifdef CONFIG_CC_IS_CLANG + CFLAGS_REMOVE_vgettimeofday-32.o += -fno-stack-clash-protection + endif CFLAGS_vgettimeofday-64.o += -include $(c-gettimeofday-y) CFLAGS_vgettimeofday-64.o += $(DISABLE_LATENT_ENTROPY_PLUGIN) CFLAGS_vgettimeofday-64.o += $(call cc-option, -fno-stack-protector) |