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Date: Sat, 30 May 2009 15:29:39 -0700 (PDT)
From: Linus Torvalds <torvalds@linux-foundation.org>
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To: "Larry H." <research@subreption.com>
cc: linux-mm@kvack.org, Alan Cox <alan@lxorguk.ukuu.org.uk>,
       Rik van Riel <riel@redhat.com>, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] Change ZERO_SIZE_PTR to point at unmapped space
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On Sat, 30 May 2009, Larry H. wrote:
> 
> The ZERO_OR_NULL_PTR macro is changed accordingly. This patch does
> not modify its behavior nor has any performance nor functionality
> impact.

I'm sure it makes a code generation difference, with (a) big constants and 
(b) no longer possible to merge the conditional into one single one.

		Linus