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Date: Thu, 27 Feb 2014 13:18:00 -0000
Message-ID: <CA+1=iYYveHL7i=yT0XRpc=HeBt5rqVMP8JWLuNOGtEU2nkiLLQ@mail.gmail.com>
Subject: Re: Compiler optimizing variables in inline assembly
From: Cody Rigney <codyrigney92@gmail.com>
To: Andrew Haley <aph@redhat.com>
Cc: gcc-help@gcc.gnu.org
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X-SW-Source: 2014-02/txt/msg00157.txt.bz2

> On Fri, Feb 21, 2014 at 10:02 AM, Andrew Haley <aph@redhat.com> wrote:
>> It's hard for me to give a 100% answer to that one, but GCC has an
>> idea what memory is reachable from every pointer.  So, this won't
>> clobber memory that's unreachable or has a different type from that
>> pointer.  It probably doesn't matter.
>>

Doing "=m" (*a) in the output operand worked! And so did "memory" to
the clobber list. Thanks!