Re: [PATCH 2/2] selftests/lib.mk: silence some clang warnings that gcc already ignores

[Shuah Khan <skhan@linuxfoundation.org>]

On 5/28/24 20:08, John Hubbard wrote:
> gcc defaults to silence (off) for the following warnings, but clang
> defaults to the opposite. These warnings are not useful for kselftests,
> so silence them for the clang builds as well:

Please you add more information on why they aren't useful
for kselftests.

> 
>      -Wno-address-of-packed-member
>      -Wno-gnu-variable-sized-type-not-at-end
> 
> This eliminates warnings for the net/ and user_events/ kselftest
> subsystems, in these files:
> 
>      ./net/af_unix/scm_rights.c
>      ./net/timestamping.c
>      ./net/ipsec.c
>      ./user_events/perf_test.c
> 
> Cc: Nathan Chancellor <nathan@kernel.org>
> Signed-off-by: John Hubbard <jhubbard@nvidia.com>
> ---
>   tools/testing/selftests/lib.mk | 6 ++++++
>   1 file changed, 6 insertions(+)
> 
> diff --git a/tools/testing/selftests/lib.mk b/tools/testing/selftests/lib.mk
> index 2902787b89b2..41e879f3f8a2 100644
> --- a/tools/testing/selftests/lib.mk
> +++ b/tools/testing/selftests/lib.mk
> @@ -50,6 +50,12 @@ else
>   CLANG_FLAGS     += --target=$(notdir $(CROSS_COMPILE:%-=%))
>   endif # CROSS_COMPILE
>   
> +# gcc defaults to silence (off) for the following warnings, but clang defaults
> +# to the opposite. These warnings are not useful for kselftests, so silence them
> +# for the clang builds as well.
> +CFLAGS += -Wno-address-of-packed-member
> +CFLAGS += -Wno-gnu-variable-sized-type-not-at-end
> +
>   CC := $(CLANG) $(CLANG_FLAGS) -fintegrated-as
>   else
>   CC := $(CROSS_COMPILE)gcc

thanks,
-- Shuah