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Date: Thu, 3 Jan 2002 16:26:46 -0500
From: Daniel Jacobowitz <dmj+@andrew.cmu.edu>
To: David Woodhouse <dwmw2@infradead.org>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>, linux-kernel@vger.kernel.org,
        linuxppc-dev@lists.linuxppc.org
Subject: Re: [PATCH] C undefined behavior fix
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On Thu, Jan 03, 2002 at 12:35:30AM +0000, David Woodhouse wrote:
> 
> (cc list trimmed)
> 
> alan@lxorguk.ukuu.org.uk said:
> >  If you want a strcpy that isnt strcpy then change its name or use a
> > different language 8)
> 
> The former is not necessarily sufficient in this case. You've still done the
> broken pointer arithmetic, so even if the function isn't called strcpy() the
> compiler is _still_ entitled to replace it with a call to memcpy() or even
> machine_restart() before sleeping with your mother and starting WW III.

No, that's not true.  We're passing a pointer as an argument.  It is a
valid pointer - dereferencing it may not be valid, but the pointer is
perfectly legal!  There is nothing wrong with this case.  The problem
lies in calling a function whose name is special to GCC and to the C
language, which GCC can then transform.

-- 
Daniel Jacobowitz                           Carnegie Mellon University
MontaVista Software                         Debian GNU/Linux Developer
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