[vlc-devel] possible race condition

xxcv xxcv07 at gmail.com
Sat May 16 03:26:06 CEST 2009

Hello all,
Someone broke my trac account and I can't post a ticket although I can 
still login.
I recently encountered this problem where goom plugin will crash if gcc 
optimized vlc binary.
[0x5cdb59c] mpgatofixed32 audio output debug: libmad error: bad 
main_data_begin pointer
[0x5cdbb84] main generic debug: thread started
[New thread 4224.0x1834]
[New thread 4224.0x15e4]
[New thread 4224.0x1934]
[New thread 4224.0x1134]

Program received signal SIGSEGV, Segmentation fault.
[Switching to thread 4224.0x1134]
0x669984d7 in zoom_filter_xmmx ()
   from plugins\libgoom_plugin.dll
(gdb) bt
#0  0x669984d7 in zoom_filter_xmmx ()
   from plugins\libgoom_plugin.dll
#1  0x66982ed7 in goom_update ()
   from plugins\libgoom_plugin.dll
#2  0x66981d38 in Thread (p_this=0x5cdbb84) at goom.c:359
#3  0x6a5c1c81 in thread_entry (data=0x5ce4900) at misc/threads.c:1061
#4  0x6a5c2447 in vlc_entry (data=0x5e51838) at misc/threads.c:741

It appears that the problem exist in the audio filter part of vlc. It 
sometimes will crash sometimes not,
but most of the time will crash when goom visualization is called. As 
you can see it segfaults shortly after
calling goom_update(). Seems likely that there's a problem with the 
libvlccore I think.
I also encountered this similar problem when scaletempo gets a p_filter 
NULL pointer at different line of the
scaletempo module. p_filter becomes NULL before the module could 
actually finish.
It is strange that the library thread got called too late. Maybe who is 
responsible of the threading part of the code
should polish it up a bit and stop been a slacker! Same to the person 
who is responsible for gui part of the code (go to hell).

Sorry for saying this but I get cyber (bullied) abused on trac tickets 
and that's enough. If you don't think it is a bug or you'd
want to ignore tickets and release "shit" then whatever, like I ever 
cared about your project? Been wasting too much of
my time helping you fixing (most stupid mistakes you made) bugs that 
you'd never fix.

I don't know what you're thinking but I'm just a "user" wants to report 
bugs, not a programmer.

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