I'm getting a segfault from qemu-system-sparc with the io thread enabled on win32. This is with the latest mingw (gcc 4.6.1). mipsel also fails, but i386 is ok. I haven't checked any of the other system targets, but they might also show this problem.
git bisect points to commit cea5f9a cpu-exec.c: avoid AREG0 use, but that would seem to only expose the bug instead of creating it. In cpu_exec(), assigning any valid pointer to ebp before setjmp will get it working again. It looks like a bogus value in ebp at the time of setjmp will cause longjmp to abort on win32. Here's some output from gdb for the crash: Starting program: d:\qemu\build-mingw\sparc-softmmu\qemu-system-sparc.exe -m 64 -L ./qemu-git/pc-bios [New Thread 2128.0x664] [New Thread 2128.0x5d4] [New Thread 2128.0x6dc] [Switching to Thread 2128.0x6dc] Breakpoint 1, 0x00514a30 in _setjmp () (gdb) info registers eax 0x1989b7c 26778492 ecx 0x1982008 26746888 edx 0x0 0 ebx 0x1982008 26746888 esp 0x378fe00 0x378fe00 ebp 0xfffffffe 0xfffffffe esi 0x0 0 edi 0x1982008 26746888 eip 0x514a30 0x514a30 <_setjmp> eflags 0x202 [ IF ] cs 0x1b 27 ss 0x23 35 ds 0x23 35 es 0x23 35 fs 0x38 56 gs 0x0 0 (gdb) c Continuing. Program received signal SIGSEGV, Segmentation fault. 0x7800bd65 in abnormal_termination () from C:\WINNT\system32\msvcrt.dll (gdb) bt #0 0x7800bd65 in abnormal_termination () from C:\WINNT\system32\msvcrt.dll #1 0x0378ffa4 in ?? () Backtrace stopped: previous frame inner to this frame (corrupt stack?) Bob
