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Date: Thu, 30 Jun 2011 20:04:24 -0400
From: Frank Peters <frank.peters@comcast.net>
To: gentoo-amd64@lists.gentoo.org
Subject: Re: [gentoo-amd64] Re: GCC-4.5.2 Has Serious Problems
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On Fri, 01 Jul 2011 02:44:36 +0300
Nikos Chantziaras <realnc@arcor.de> wrote:

> >
> > Your code is buggy, because you're breaking C's aliasing rules. You are
> > not allowed to use a different pointer type to dereference a variable of
> > a different type. Doing so results in undefined behavior.
> 

Well, the error occurs only within the loop structure.  If
I manually "unroll" the loop using the same pointers there
is no error when compiled with "O2." 

IOW, the problem is how the loop is optimized under -O2.

Frank Peters