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Date: Fri, 16 Jan 2009 01:38:34 -0800
From: Andrew Morton <akpm@linux-foundation.org>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Wu Fengguang <wfg@linux.intel.com>, L-K <linux-kernel@vger.kernel.org>
Subject: Re: generic swap()
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On Fri, 16 Jan 2009 10:26:34 +0100 Peter Zijlstra <peterz@infradead.org> wrote:

> Hi,
> 
> Where did this patch come from? -- I can't seem to find it on lkml at all..

That's a damn good question.  I received:

From: Wu Fengguang <fengguang.wu@intel.com>
To: Andrew Morton <akpm@linux-foundation.org>
Cc: LKML <linux-kernel@vger.kernel.org>
Subject: [PATCH 0/9] [PATCH] make swap() a global macro
Date: Tue, 02 Dec 2008 19:45:24 +0800
User-Agent: quilt/0.46-1

but the cc didn't seem to work.  quilt bustage?

> The reason I ask it that I wonder why swap() has a return value?

Accident, I guess.

> +#define swap(a, b) ({ typeof(a) __tmp = (a); (a) = (b); (b) = __tmp; })

You think it should use the do{}while(0) thing?