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Date: Fri, 10 Jun 2011 14:32:00 -0000
From: Jason Merrill <jason@redhat.com>
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To: Richard Guenther <rguenther@suse.de>
CC: Richard Guenther <richard.guenther@gmail.com>,        gcc-patches List <gcc-patches@gcc.gnu.org>
Subject: Re: RFA (fold): PATCH for c++/49290 (folding *(T*)(ar+10))
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On 06/10/2011 10:03 AM, Richard Guenther wrote:
>>> *((volatile int *)&a[0] + 1)
>>
>> It would be correct to fold it to
>>
>> VIEW_CONVERT_EXPR<volatile int,a[1]>
>
> No, it wouldn't be correct.  It isn't correct to fold it to an array-ref
> that isn't volatile.

Hmm?  The C expression produces a volatile int lvalue referring to the 
second element of a, as does the VIEW_CONVERT_EXPR.  They seem 
equivalent to me.

Jason