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Date: Fri, 17 May 2013 09:49:00 -0300
From: Lucas Meneghel Rodrigues <lmr@redhat.com>
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Subject: Re: [Qemu-devel] [PATCH] tests: set MALLOC_PERTURB_ to expose
 memory bugs
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To: "Daniel P. Berrange" <berrange@redhat.com>
Cc: Markus Armbruster <armbru@redhat.com>, Stefan Hajnoczi <stefanha@redhat.com>, qemu-devel@nongnu.org

On 17/05/13 07:07 AM, Daniel P. Berrange wrote:
>> If you want punishment, why not go for extra punishment?
>>
>> MALLOC_PERTURB_=$(($RANDOM % 255 + 1))
>
> That could lead to non-reproducable failures though. I think it is better
> to use a fixed value so that you're more likely to be able to reproduce
> the issue every time you run the tests.
>
> Rather than setting MALLOC_PERTURB_=1 unconditionally in the Makefile
> though, it ought to honour any existing MALLOC_PERTURB_ env variable
> the user has set. That could let automated test harness run repeatedly
> with random MALLOC_PERTURB_, while still giving a deterministic value
> for developers by default.

Indeed. I've never thought about it, thanks for sharing the insight.