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Date: Sat, 9 Aug 2003 01:51:42 -0700
From: "David S. Miller" <davem@redhat.com>
To: Willy Tarreau <willy@w.ods.org>
Cc: jamie@shareable.org, albert@users.sourceforge.net,
       linux-kernel@vger.kernel.org, chip@pobox.com
Subject: Re: [PATCH] 2.4.22pre10: {,un}likely_p() macros for pointers
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On Sat, 9 Aug 2003 10:13:46 +0200
Willy Tarreau <willy@w.ods.org> wrote:

> (how could !!x be 0 if x isn't ?)

I believe the C language allows for systems where the NULL pointer is
not zero.

I can't think of any reason why the NULL macro exists otherwise.

However, even if I'm right, I dread the guy who has to make other
people's code work on such a platform.  Using normal boolean tests for
NULL pointer checks is just too common.