Re: [PATCH] 2.4.22pre10: {,un}likely_p() macros for pointers

From: Jamie Lokier
Date: Sat Aug 09 2003 - 04:40:56 EST


David S. Miller wrote:
> On Sat, 9 Aug 2003 10:13:46 +0200 Willy Tarreau <willy@xxxxxxxxx> 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.

That is irrelevant. The GCC manual says you can't use a pointer as
the argument to __builtin_expect anyway:

Since you are limited to integral expressions for EXP, you should
use constructions such as

if (__builtin_expect (ptr != NULL, 1))
error ();

when testing pointer or floating-point values

-- Jamie
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