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Sender: Richard Henderson <rth7680@gmail.com>
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Date: Thu, 18 Jul 2013 10:09:36 -0700
From: Richard Henderson <rth@twiddle.net>
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Subject: Re: [Qemu-devel] [PATCH] util/iov: Fix -O1 uninitialized variable
 warning
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To: Peter Maydell <peter.maydell@linaro.org>
Cc: aliguori@us.ibm.com, qemu-devel@nongnu.org

On 07/18/2013 09:36 AM, Peter Maydell wrote:
> On 18 July 2013 17:14, Richard Henderson <rth@twiddle.net> wrote:
>> At -O2, code in the form
>>
>>   if (p) A; B; if (p) C;
>>
>> may be rearranged via "jump threading" into
>>
>>   if (p) { A; B; C; } else { B; }
>>
>> But at -O1 this doesn't happen and we -Werror out here on
>> the "may be used uninitialized" orig_len.  Perform this transform
>> by hand so that -O1 remains a viable debugging alternative.
>>
>> Signed-off-by: Richard Henderson <rth@twiddle.net>
> 
> This is the same issue fixed by this (reviewed but
> never applied) patch from June, isn't it?
> 
> http://patchwork.ozlabs.org/patch/251410/

Yes, it is.


r~