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From: Peter Maydell <peter.maydell@linaro.org>
Date: Thu, 18 Jul 2013 17:36:20 +0100
Message-ID: <CAFEAcA_crhJopBsB-cby8n2piKBh=5u+=xMoW+UrSUSUdsbM6g@mail.gmail.com>
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Subject: Re: [Qemu-devel] [PATCH] util/iov: Fix -O1 uninitialized variable
	warning
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To: Richard Henderson <rth@twiddle.net>
Cc: aliguori@us.ibm.com, qemu-devel@nongnu.org

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/

thanks
-- PMM