From mboxrd@z Thu Jan  1 00:00:00 1970
From: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>
Subject: Re: Potential incorrect simplification
Date: Tue, 28 Mar 2017 16:11:14 +0200
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To: Dibyendu Majumdar <mobile@majumdar.org.uk>
Cc: Linux-Sparse <linux-sparse@vger.kernel.org>

On Tue, Mar 28, 2017 at 02:58:57PM +0100, Dibyendu Majumdar wrote:
> Hi Luc,
> 
> 
> The first instruction and.32 refers to %r4 which is undefined.

Yes, I saw.
This %r4 corresponds (somehow) to s3 which isn't initialized.

But yes, there is two problems here:
*) we should use something explicit, like VOID
*) there is a circulary dependence between %r3 & %r4, the first %r4
   being obviously wrong.

I suspect there is a lot of problems present once there is some
undefined variables.

Thanks for the repoort.

-- Luc