[iiwusynth-devel] Re: [Swami-devel] iiwusynth segfault

[Mark Knecht]

On Thu, 2003-01-23 at 01:31, Josh Green wrote:
> 
> What I would suggest is that you compile FluidSynth with debugging
> enabled "./configure --enable-debug" and then get some back traces on
> the lockups and segfaults by running FluidSynth through gdb:

address@hidden iiwusynth]# ./configure --enable-debug
--disable-oss-support --enable-jack-support
<SNIP>

**************************************************************
Summary:
ALSA:                  yes
OSS:                   no
MidiShare:             no
JACK:                  yes
Readline:              yes
Debug:                 yes
Profiling:             no
LADSPA support:        no
use long long:         no
Pentium 3+ SSE:        no
**************************************************************


Running without gdb first:

address@hidden mark]$ iiwusynth -a jack
iiwusynth: debug: Using 'jack' audio driver

iiwusynth: debug: Jack engine sample rate: 44100

Segmentation fault
address@hidden mark]$


> 
> > gdb iiwusynth
> 
> (gdb) set args -a jack
> (gdb) r
> 
> wait for segfault
> 

OK, unless it takes a really long time to get the segfault, I waited
about 10 minutes and it didn't happen. I did get this interesting
message:

address@hidden mark]$ gdb iiwusynth
GNU gdb Red Hat Linux (5.2-2)
Copyright 2002 Free Software Foundation, Inc.
GDB is free software, covered by the GNU General Public License, and you
are
welcome to change it and/or distribute copies of it under certain
conditions.
Type "show copying" to see the conditions.
There is absolutely no warranty for GDB.  Type "show warranty" for
details.
This GDB was configured as "i386-redhat-linux"...
(gdb) set args -a jack
(gdb) r
Starting program: /usr/local/bin/iiwusynth -a jack
[New Thread 1024 (LWP 7323)]
iiwusynth: debug: Using 'jack' audio driver

iiwusynth: debug: Jack engine sample rate: 44100

[New Thread 2049 (LWP 7324)]
Can't attach LWP 7324: Operation not permitted
(gdb)





> (gdb) bt

(gdb) bt
#0  0x4018df61 in __linuxthreads_create_event () from
/lib/i686/libpthread.so.0
#1  0x40189bd5 in __pthread_initialize_manager () from
/lib/i686/libpthread.so.0
#2  0x4018a715 in pthread_create@@GLIBC_2.1 () from
/lib/i686/libpthread.so.0
#3  0x400f95c3 in jack_start_thread (client=0x8148d58) at client.c:766
#4  0x400f993c in jack_activate (client=0x8148d58) at client.c:934
#5  0x40040a8a in new_iiwu_jack_audio_driver (settings=0x804b3b0,
synth=0x804c2b0)
    at iiwu_jack.c:219
#6  0x400462e5 in new_iiwu_audio_driver (settings=0x804b3b0,
synth=0x804c2b0)
    at iiwu_adriver.c:224
#7  0x08049939 in main (argc=3, argv=0xbffff8f4) at iiwusynth.c:435
#8  0x42017589 in __libc_start_main () from /lib/i686/libc.so.6
(gdb)

> 
> This will give you a stack trace of where the crash occured. Post it to
> iiwusynth-devel (although you are welcome to post it here). In the case
> of running iiwusynth without specifying the driver (where you had to hit
> ctrl-c), you can do the same thing. i.e., hit control-c and the program
> will probably stop in the location that is locked, do a backtrace (bt).
> 
> That will help us figure out whats going on. Cheers.
>       Josh Green

I hope this is helpful!

Cheers,
Mark