Bug#842796: ogg123 always segfaults after playing file

[Ian Jackson]

Petter Reinholdtsen writes ("Re: Bug#842796: ogg123 always segfaults after playing file"):
> [Ian Jackson]
> > This started happening after I moved my OS install to a new computer.
> > But I also probably did an apt-get upgrade.  So the trigger was
> > probably either an update, or running on a new CPU.
> 
> That sound nasty.  Can you try to install debug symbols and see if you
> can reproduce the crash under valgrind?

It works fine under valgrind (!).

I ran it under gdb, and:

$ gdb --args ogg123 -d null Example.ogg 
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Reading symbols from ogg123...Reading symbols from /usr/lib/debug/.build-id/b3/fec92d31ddc4115a618db4fb2fcd5f555e3f2b.debug...done.
done.
(gdb) run
Starting program: /usr/bin/ogg123 -d null Example.ogg
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/i386-linux-gnu/i686/cmov/libthread_db.so.1".

Audio Device:   Null output

[New Thread 0xf6b56b40 (LWP 32037)]
Playing: Example.ogg
Ogg Vorbis stream: 2 channel, 44100 Hz
[Thread 0xf6b56b40 (LWP 32037) exited] (136.0 kbps)  Output Buffer   0.5% (EOS)
Time: 00:06.10 [00:00.00] of 00:06.10  (136.0 kbps)  Output Buffer   0.0% (EOS) 
Program received signal SIGSEGV, Segmentation fault.
__lll_unlock_elision (lock=lock at entry=0x805d6cc <output_lock>, private=0)
    at ../nptl/sysdeps/unix/sysv/linux/x86/elision-unlock.c:29
29      ../nptl/sysdeps/unix/sysv/linux/x86/elision-unlock.c: No such file or directory.
(gdb) bt
#0  __lll_unlock_elision (lock=lock at entry=0x805d6cc <output_lock>, private=0)
    at ../nptl/sysdeps/unix/sysv/linux/x86/elision-unlock.c:29
#1  0xf7ed5080 in __pthread_mutex_unlock_usercnt (mutex=mutex at entry=0x805d6cc <output_lock>, decr=decr at entry=1)
    at pthread_mutex_unlock.c:66
#2  0xf7ed511e in __GI___pthread_mutex_unlock (mutex=0x805d6cc <output_lock>) at pthread_mutex_unlock.c:310
#3  0x0805125d in status_reset_output_lock () at status.c:342
#4  0x0804fa49 in play (source_string=0x807ccf0 "x\333\b\bP\244\341", <incomplete sequence \367>) at ogg123.c:746
#5  0x0804ac28 in main (argc=4, argv=0xffffd964) at ogg123.c:496
(gdb) 

Ian.