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FPU incorrect on Mac OS X
I am using the 0.13.0 release version of QEMU on Mac OS X 10.6.4. I work for a university and the affected guest OS is our own research OS. I believe I found a bug in QEMU's FPU emulation, which only triggers on the Mac. You can reproduce the problem by booting the attached ISO image.
Investigating the problem, I found that the lua interpreter in our loader component (called "ned") internally uses doubles to represent all lua-numbers. These doubles are showing completely wrong values on QEMU/Mac, resulting in the lua code not processing properly.
I also attached a patch which fixes the problem for me. The attached ZIP-file also contains "before" and "after" screenshots. Note that booting the ISO on a real machine or on a Linux-QEMU always shows the correct "after" behavior. Only QEMU on the Mac exhibits the wrong "before" behavior without my patch. The patch might break other systems setting the CONFIG_BSD flag, so maybe the preprocessor should check for __APPLE__ instead to make the fix Mac-only.
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