Date: Mon, 10 Nov 2008 08:45:37 +0100
From: Ingo Molnar <mingo@elte.hu>
To: Harvey Harrison <harvey.harrison@gmail.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>, Thomas Gleixner <tglx@linutronix.de>,
       LKML <linux-kernel@vger.kernel.org>
Subject: Re: [RFC-PATCH] x86: really use __builtin_memcmp on x86_32
Message-ID: <20081110074536.GB2093@elte.hu>
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* Harvey Harrison <harvey.harrison@gmail.com> wrote:

> Impact: prevent generic code from overriding __builtin_memcmp
> 
> lib/string.c was using a generic implementation of memcmp
> because __HAVE_ARCH_MEMCMP was not defined and it was then doing
> #undef memcmp and defining a generic version.
> 
> Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
> ---
>  arch/x86/include/asm/string_32.h |    1 +
>  1 files changed, 1 insertions(+), 0 deletions(-)

> +#define __HAVE_ARCH_MEMCMP
>  #define memcmp __builtin_memcmp
>  
>  #define __HAVE_ARCH_MEMCHR

on a quick look, since x86 sets __HAVE_ARCH_STRSTR, nothing in 
lib/string.c would actually use this generic (and slower) memcmp 
implementation, correct? So there should be no impact to object code, 
it's a cleanup - right?

	Ingo
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