Attempting to debug rfbsrc plugin

[Peter Watkins]

I'd like to use the rfbsrc plugin for a project I'm working on. I know 
it's a "bad" plugin, but it does exactly what I want. To test it, I ran 
gst-launch with the following command:

gst-launch rfbsrc host=10.130.6.61 password=secret width=1024 height=768 
view-only=true ! videoscale ! videorate ! 
video/x-raw-rgb,width=1024,height=768,framerate=10/1 ! ffmpegcolorspace ! 
autovideosink

I'm new to gstreamer so that pipeline might have some unnecessary pieces. 
Let me know if it does.

After about 10 seconds, gst-launch hits a segmentation violation:

WARNING: from element 
/GstPipeline:pipeline0/GstAutoVideoSink:autovideosink0/GstXImageSink:autovideosink0-actual-sink-ximage: 
A lot of buffers are being dropped.
Additional debug info:
gstbasesink.c(2597): gst_base_sink_is_too_late (): 
/GstPipeline:pipeline0/GstAutoVideoSink:autovideosink0/GstXImageSink:autovideosink0-actual-sink-ximage:
There may be a timestamping problem, or this computer is too slow.
Caught SIGSEGV accessing address 0x7fb1f0f67a90
#0  0x00007fb1f55baf93 in ?? ()
#1  0x0000000000871a80 in ?? ()
#2  0x00000000000000f9 in ?? ()
#3  0x0000000000000001 in ?? ()
#4  0x0000000000871a80 in ?? ()
#5  0x0000000000707218 in ?? ()
#6  0x00007fb1f5ac34a9 in ?? ()
#7  0x0000000000707210 in ?? ()
#8  0x00007fb1000000f9 in ?? ()
#9  0x00007fb1f5d5d788 in ?? ()
#10 0x00007fb1f5d5d7c0 in ?? ()
#11 0x0000000100000001 in ?? ()
#12 0x0000000000707218 in ?? ()
#13 0x00000000ffffffff in ?? ()
#14 0x7fffffff000000f9 in ?? ()
#15 0x00000000008b2e50 in ?? ()
#16 0x00000000008b2f90 in ?? ()
#17 0x00000000006b8080 in ?? ()
#18 0x00007fb1f5d5de60 in ?? ()
#19 0x0000000000000001 in ?? ()
#20 0x00000000008b2f9c in ?? ()
#21 0x0000000000000000 in ?? ()
Spinning.  Please run 'gdb gst-launch 8038' to continue debugging, Ctrl-C 
to quit, or Ctrl-\ to dump core.

So I'd like to poke around in GDB and try to see what the problem is. I'm 
on Ubuntu 10.04 64 bit, I've installed the debug symbols for gstreamer, 
gstreamer-bad-plugins, and libc6.

When I run GDB, the debug symbols seem to load:

user at fermi:~/gstreamer0.10-0.10.28/tools$ gdb gst-launch 8038
GNU gdb (GDB) 7.1-ubuntu
Copyright (C) 2010 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later 
<http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.  Type "show copying"
and "show warranty" for details.
This GDB was configured as "x86_64-linux-gnu".
For bug reporting instructions, please see:
<http://www.gnu.org/software/gdb/bugs/>...
Reading symbols from /usr/bin/gst-launch...Reading symbols from 
/usr/lib/debug/usr/bin/gst-launch...done.
done.
Attaching to program: /usr/bin/gst-launch, process 8038
Reading symbols from /lib64/ld-linux-x86-64.so.2...Reading symbols from 
/usr/lib/debug/lib/ld-2.11.1.so...done.
done.
Loaded symbols for /lib64/ld-linux-x86-64.so.2
0x00007fb1f55baf93 in ?? ()
(gdb)


However, I can't seem to print a backtrace or display any variables:

(gdb) bt
#0  0x00007fb1f55baf93 in ?? ()
#1  0x0000000000871a80 in ?? ()
#2  0x00000000000000f9 in ?? ()
#3  0x0000000000000001 in ?? ()
#4  0x0000000000871a80 in ?? ()
#5  0x0000000000707218 in ?? ()
#6  0x00007fb1f5ac34a9 in ?? ()
#7  0x0000000000707210 in ?? ()
#8  0x00007fb1000000f9 in ?? ()
#9  0x00007fb1f5d5d788 in ?? ()
#10 0x00007fb1f5d5d7c0 in ?? ()
#11 0x0000000100000001 in ?? ()
#12 0x0000000000707218 in ?? ()
#13 0x00000000ffffffff in ?? ()
#14 0x7fffffff000000f9 in ?? ()
#15 0x00000000008b2e50 in ?? ()
#16 0x00000000008b2f90 in ?? ()
#17 0x00000000006b8080 in ?? ()
#18 0x00007fb1f5d5de60 in ?? ()
#19 0x0000000000000001 in ?? ()
#20 0x00000000008b2f9c in ?? ()
#21 0x0000000000000000 in ?? ()
(gdb) info locals
No symbol table info available.
(gdb) info args
No symbol table info available.


Maybe this is a question for the GDB list, but does anyone have any idea 
why I can't seem to get much debugging info for gstreamer?

Thanks,

Peter
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