[Bug 28388] winmm/midi.ok deadlocks and crashes occasionally?

http://bugs.winehq.org/show_bug.cgi?id=28388

--- Comment #6 from Dan Kegel  2011-09-29 00:07:30 CDT ---
I ran the test in a loop; after about 200 runs, on two different
machines, it hit the problem.  I got lucky and was there when
it happend once, and did btall, which gave a good backtrace
for one of the two threads involved in the deadlock:

=>0 HEAP_FindFreeBlock+0x49(heap=0x110000, size=0x100, ppSubHeap=0x73e53c)
[dlls/ntdll/heap.c:990] 
  1 RtlAllocateHeap+0x1fd(heap=0x110000, flags=0x2, size=0x100)
[dlls/ntdll/heap.c:1675] 
  2 peek_message+0x84(msg=0x73e9d0, hwnd=(nil), first=0, last=0,
flags=0x4ff0001, changed_mask=0x4ff) [dlls/user32/message.c:2612]
  3 GetMessageW+0x151(msg=0x73e9d0, hwnd=(nil), first=0, last=0)
[dlls/user32/message.c:3610] 
  4 GetMessageA+0x5f(msg=0x73e9d0, hwnd=(nil), first=0, last=0)
[dlls/user32/message.c:3625] 
  5 MMSYSTEM_MidiStream_Player+0x132(pmt=0x129328) [dlls/winmm/winmm.c:1155] 
  6 call_thread_func+0xb()

The other thread didn't have a backtrace, all it showed was that it was
in a linux system call.