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Date: Sun, 9 Apr 2006 10:49:12 +0200
From: Lyonel Vincent <lyonel.vincent@gmail.com>
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Subject: [Qemu-devel] [resend] i386 emulation on PowerPC host
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To: qemu-devel@nongnu.org

Hi all,

Having noticed very wierd behaviour of some operations under an x86
Qemu guest running on a PowerPC (32 bits), I have compiled the
following test program under Linux/i386:

#include <stdio.h>
#include <math.h>

void main()
{
  float x = exp(1)*exp(1);
  float y = exp(2);

  printf("%f = %f\n", x, y);
}

When run under native i386 Linux, this program displays:
$ ./mathtest
7.389056 = 7.389056

as expected

but with a CVS snapshot (as of 2006-03-23) of Qemu, one gets:
$ ./mathtest
7.389056 = -inf

[that's the same binary running under Linux/i386 inside Qemu on a
PowerPC host]

I also have other strange symptoms like cp sometimes complaining about
memory exhaustion but I haven't been able to reproduce those yet...

Does anybody have an idea of what the problem could be and how I could
help to fix that?

cheers,
Lyonel.