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Date: Wed, 11 Mar 2009 00:40:20 -0300
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From: Glauber Costa <glommer@gmail.com>
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Subject: [Qemu-devel] TCG/GCC breakage
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To: "qemu-devel@nongnu.org" <qemu-devel@nongnu.org>

I'm seeing a strange behaviour here using qemu-system-x86_64
(kvm not even compiled in) on an i386 host

I'm suspecting gcc is doing something nasty in here, but I'll open it
up here to see if any
of you have any suggestion.

I get segfaults very early in execution, and after some investigation,
I figured out that
ebp register is corrupted. I can't determine where the corruption starts.

I then did rm x86-64-softmmu/op_helper.o; make CC=gcc34, so only this
file get compiled
by an older gcc, and it worked again.

So it seems to me gcc may be generating gibberish somewhere in
helpers, but since
this code is a bit fragile, it might well be some mistake on our part.

Ideas on how to attack it ?

-- 
Glauber  Costa.
"Free as in Freedom"
http://glommer.net

"The less confident you are, the more serious you have to act."