Re: [PATCH] x86: undef REG_IN/REG_OUT to avoid define collisions

[Dave Hansen <dave.hansen@intel.com>]

On 3/30/22 08:28, Neil Armstrong wrote:
> These defines are only used in the inline functions declared
> in the arch_hweight.h file, and collides with internal defines
> of the Amlogic Mes pinctrl driver when COMPILE_TEST is enabled:
> 
> arch/x86/include/asm/arch_hweight.h:9:17: error: expected identifier before string constant
> 9 | #define REG_OUT "a"
>   |                 ^~~
> drivers/pinctrl/meson/pinctrl-meson.h:69:9: note: in expansion of macro ‘REG_OUT’
> 69 |         REG_OUT,
> 
> Reported-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
> ---
>  arch/x86/include/asm/arch_hweight.h | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/arch/x86/include/asm/arch_hweight.h b/arch/x86/include/asm/arch_hweight.h
> index ba88edd0d58b..139a4b0a2a14 100644
> --- a/arch/x86/include/asm/arch_hweight.h
> +++ b/arch/x86/include/asm/arch_hweight.h
> @@ -52,4 +52,7 @@ static __always_inline unsigned long __arch_hweight64(__u64 w)
>  }
>  #endif /* CONFIG_X86_32 */
>  
> +#undef REG_IN
> +#undef REG_OUT

Wouldn't it be a bit less hackish to give these a more qualified name
like HWEIGHT_REG_IN?