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Date: Thu, 16 Feb 2012 12:15:30 +0100
From: Kevin Wolf <kwolf@redhat.com>
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Subject: Re: [Qemu-devel] [Bug 932487] [NEW] win32: git rev 59f971d crashes
 when accessing disk (coroutine issue)
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To: Paolo Bonzini <pbonzini@redhat.com>
Cc: qemu-devel@nongnu.org

Am 16.02.2012 12:01, schrieb Paolo Bonzini:
> On 02/16/2012 11:34 AM, Kevin Wolf wrote:
>> Remember that I saw a similar crash a while ago? It was definitely a
>> NULL pointer access somewhere inside SwitchToFiber. I can't remember
>> exactly what came out of it, but I think you and Paolo couldn't
>> reproduce it and I ran out of time for debugging win32 stuff.
>>
>> If I was to debug this, the first thing I would try is that I would dump
>> co->fiber (or actually I seem to remember it was some data structure
>> that is only pointed to by a field in co->fiber) immediately after the
>> coroutine is created (I think it was still okay then) and set a
>> watchpoint on it.
> 
> IIRC the problem was that thread-local storage was not thread-local at all.

Ah, right. And we didn't introduce a workaround, so I guess this is the
same thing.

Do newer mingw versions get this right or were you just lucky and we
should look for some kind of workaround?

Kevin