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Date: Wed, 20 Feb 2013 10:49:42 +0100
From: Stefan Farfeleder <stefanf@FreeBSD.org>
To: David Chisnall <theraven@FreeBSD.org>
Subject: Re: svn commit: r247014 - head/lib/libc/stdlib
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On Wed, Feb 20, 2013 at 09:32:43AM +0000, David Chisnall wrote:
> On 20 Feb 2013, at 08:25, mdf@FreeBSD.org wrote:
> 
> > These should be declared const int *.  And the cast shouldn't be
> > needed in C, since void * can be assigned to any other pointer type.
> 
> In fact, the entire function body can be replaced with:
> 
>   return (*(int*)p1 - *(int*)p2);
> 
> qsort doesn't require that you return -1, 0, or 1, it requires you return <0, 0, or >0.

The subtraction might overflow and give wrong results. It won't for
these specific elements, but it would be a bad example, IMHO.

Stefan