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Subject: Re: [PATCH] 2.4.22pre10: {,un}likely_p() macros for pointers
From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: "David S. Miller" <davem@redhat.com>
Cc: Willy Tarreau <willy@w.ods.org>, jamie@shareable.org,
       albert@users.sourceforge.net,
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On Sad, 2003-08-09 at 09:51, David S. Miller wrote:
> I believe the C language allows for systems where the NULL pointer is
> not zero.

Its a fudge for some systems. However NULL == 0 is always true.

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

<OldFart>
NULL is really important in K&R C because you don't have prototypes and
sizeof(foo *) may not be the same as sizeof(int). This leads to very
nasty problems that people nowdays forget about.
</OldFart>


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