Received-SPF: pass (google.com: domain of linux-kernel+bounces-195515-linux.lists.archive=gmail.com@vger.kernel.org designates 2604:1380:4601:e00::3 as permitted sender) client-ip=2604:1380:4601:e00::3;
Message-ID: <88c64f5e-4586-4b38-b3c8-0c3af93a71ae@linuxfoundation.org>
Date: Thu, 30 May 2024 08:25:18 -0600
Precedence: bulk
MIME-Version: 1.0
User-Agent: Mozilla Thunderbird
Subject: Re: [PATCH 2/2] selftests/lib.mk: silence some clang warnings that
 gcc already ignores
To: John Hubbard <jhubbard@nvidia.com>, Shuah Khan <shuah@kernel.org>
Cc: Beau Belgrave <beaub@linux.microsoft.com>,
 Steven Rostedt <rostedt@goodmis.org>, Mark Brown <broonie@kernel.org>,
 Naresh Kamboju <naresh.kamboju@linaro.org>,
 Nick Desaulniers <ndesaulniers@google.com>,
 Justin Stitt <justinstitt@google.com>, Bill Wendling <morbo@google.com>,
 sunliming <sunliming@kylinos.cn>, Masami Hiramatsu <mhiramat@kernel.org>,
 Valentin Obst <kernel@valentinobst.de>, linux-kselftest@vger.kernel.org,
 LKML <linux-kernel@vger.kernel.org>, llvm@lists.linux.dev,
 Nathan Chancellor <nathan@kernel.org>, Shuah Khan <skhan@linuxfoundation.org>
References: <20240529020842.127275-1-jhubbard@nvidia.com>
 <20240529020842.127275-3-jhubbard@nvidia.com>
Content-Language: en-US
From: Shuah Khan <skhan@linuxfoundation.org>
In-Reply-To: <20240529020842.127275-3-jhubbard@nvidia.com>
Content-Type: text/plain; charset=UTF-8; format=flowed
Content-Transfer-Encoding: 7bit

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