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To: Andreas Schwab <schwab@suse.de>
Cc: Andi Kleen <ak@suse.de>, linux-kernel@vger.kernel.org
Subject: Re: Linux 2.4.10-pre11 -- __builtin_expect
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From: James Antill <james@and.org>
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Date: 27 Sep 2001 11:41:22 -0400
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Andreas Schwab <schwab@suse.de> writes:

> James Antill <james@and.org> writes:
> 
> |>  unlikely() also needs to be...
> |> 
> |> #define unlikely(x)  __builtin_expect(!(x), 1) 
> |> 
> |> ...or...
> |> 
> |> #define unlikely(x)  __builtin_expect(!!(x), 0) 
> 
> This is not needed, since only 0 is the likely value and !! does not
> change that.

 Yes it is, given the code...

struct blah *ptr = NULL;

if (unlikely(ptr))

...you'll get a warning from gcc because you are implicitly converting
from a pointer to a long.

-- 
# James Antill -- james@and.org
:0:
* ^From: .*james@and\.org
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