Re: [PATCH 1/2] cpufeature: avoid warning when compiling with clang

[Ard Biesheuvel]

On 15 September 2018 at 21:38, Stefan Agner <stefan@xxxxxxxx> wrote:
> The table id (second) argument to MODULE_DEVICE_TABLE is often
> referenced otherwise. This is not the case for CPU features. This
> leads to warnings when building the kernel with Clang:
>   arch/arm/crypto/aes-ce-glue.c:450:1: warning: variable
>     'cpu_feature_match_AES' is not needed and will not be emitted
>     [-Wunneeded-internal-declaration]
>   module_cpu_feature_match(AES, aes_init);
>   ^
>
> Avoid warnings by using __maybe_unused, similar to commit 1f318a8bafcf
> ("modules: mark __inittest/__exittest as __maybe_unused").
>
> Fixes: 67bad2fdb754 ("cpu: add generic support for CPU feature based module autoloading")
> Signed-off-by: Stefan Agner <stefan@xxxxxxxx>

Acked-by: Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx>

> ---
>  include/linux/cpufeature.h | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/include/linux/cpufeature.h b/include/linux/cpufeature.h
> index 986c06c88d81..84d3c81b5978 100644
> --- a/include/linux/cpufeature.h
> +++ b/include/linux/cpufeature.h
> @@ -45,7 +45,7 @@
>   * 'asm/cpufeature.h' of your favorite architecture.
>   */
>  #define module_cpu_feature_match(x, __initfunc)                        \
> -static struct cpu_feature const cpu_feature_match_ ## x[] =    \
> +static struct cpu_feature const __maybe_unused cpu_feature_match_ ## x[] = \
>         { { .feature = cpu_feature(x) }, { } };                 \
>  MODULE_DEVICE_TABLE(cpu, cpu_feature_match_ ## x);             \
>                                                                 \
> --
> 2.19.0
>