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I am trying to compile gstreamer 1.14.4 to take advantage of the webrtc module. I was able to successfully compile it using cerbero on my raspberry pi but I have an issue where when testing my webrtc application I get a segfault after I send an offer and the pipeline has started playing:

Thread 2 "gst-pc-ops" received signal SIGSEGV, Segmentation fault.

[Switching to Thread 0x75595470 (LWP 19541)]

__GI___libc_free (mem=0xe59ff000) at malloc.c:2966

2966    malloc.c: No such file or directory.

(gdb) bt

#0  __GI___libc_free (mem=0xe59ff000) at malloc.c:2966

#1  0x7608867c in g_callable_info_free_closure (callable_info=<optimized out>, 

    closure=0x76ff0008) at girepository/girffi.c:426

#2  0x760db72c in ?? ()

   from /usr/lib/python3/dist-packages/gi/_gi.cpython-36m-arm-linux-gnueabihf.so

Backtrace stopped: previous frame identical to this frame (corrupt stack?)

I cant seem to get a full backtrace on my pi.

in valgrind I get the following when it segfaults:

==20539== Thread 2 gst-pc-ops:

==20539== Invalid read of size 8

==20539==    at 0x4865DD0: ??? (in /usr/lib/arm-linux-gnueabihf/libarmmem.so)

==20539==  Address 0x55ffab4 is 4 bytes inside a block of size 11 alloc'd

==20539==    at 0x4847568: malloc (vg_replace_malloc.c:299)

==20539==    by 0x63B4AEB: g_malloc (gmem.c:94)

==20539==    by 0x63CF46B: g_strdup (gstrfuncs.c:363)

==20539==    by 0x63341DF: g_signal_newv (gsignal.c:1644)

==20539==    by 0x633534B: g_signal_new_valist (gsignal.c:1902)

==20539==    by 0x63353C3: g_signal_new (gsignal.c:1437)

==20539==    by 0xCE1B427: gst_srtp_enc_class_init (gstsrtpenc.c:330)

==20539==    by 0xCE1B427: gst_srtp_enc_class_intern_init (gstsrtpenc.c:198)

==20539==    by 0x633FF03: type_class_init_Wm (gtype.c:2232)

==20539==    by 0x633FF03: g_type_class_ref (gtype.c:2947)

==20539==    by 0x6324EBF: g_object_new_with_properties (gobject.c:1935)

==20539==    by 0x63256DF: g_object_new (gobject.c:1637)

==20539==    by 0x6CA134B: gst_element_factory_create (gstelementfactory.c:372)

==20539==    by 0x6CA154F: gst_element_factory_make (gstelementfactory.c:445)

SNIP....

==20539== Invalid free() / delete / delete / realloc()

==20539==    at 0x4848B8C: free (vg_replace_malloc.c:530)

==20539==    by 0x62E467B: g_callable_info_free_closure (girffi.c:426)

==20539==    by 0x629A72B: ??? (in /usr/lib/python3/dist-packages/gi/_gi.cpython-36m-arm-linux-gnueabihf.so)

==20539==  Address 0xe59ff000 is not stack'd, malloc'd or (recently) free'd

==20539== 

==20539== 

==20539== Process terminating with default action of signal 6 (SIGABRT)

==20539==    at 0x498E45C: raise (raise.c:51)

==20539==    by 0x498F823: abort (abort.c:89)

==20539==    by 0x64B31DF: ffi_closure_free (in /usr/lib/arm-linux-gnueabihf/libffi.so.6.0.4)

==20539== 

==20539== HEAP SUMMARY:

==20539==     in use at exit: 12,292,940 bytes in 41,975 blocks

==20539==   total heap usage: 102,319 allocs, 60,345 frees, 45,174,025 bytes allocated

==20539== 

==20539== LEAK SUMMARY:

==20539==    definitely lost: 1,368 bytes in 26 blocks

==20539==    indirectly lost: 607 bytes in 15 blocks

==20539==      possibly lost: 3,243,651 bytes in 137 blocks

==20539==    still reachable: 8,839,230 bytes in 40,653 blocks

==20539==                       of which reachable via heuristic:

==20539==                         newarray           : 1,332 bytes in 41 blocks

==20539==         suppressed: 0 bytes in 0 blocks

==20539== Rerun with --leak-check=full to see details of leaked memory

==20539== 

==20539== For counts of detected and suppressed errors, rerun with: -v

==20539== Use --track-origins=yes to see where uninitialised values come from

==20539== ERROR SUMMARY: 3027 errors from 213 contexts (suppressed: 147 from 16)

Aborted

I compiled it using cerbero on my ubuntu x64 bit machine and it compiled fine and I was able to run the application with out issue. I am not sure how I should proceed?

I set my ~/.cerbero/cerbero.cbc to:

# For Linux

prefix='/opt/gstreamer'

recipes_commits = {

#  'ffmpeg' : '3.4.5',

#  'ffmpeg-static' : '3.4.5',

  'gstreamer-1.0' : '1.14.4',

  'gstreamer-1.0-static' : '1.14.4',

  'gst-plugins-base-1.0' : '1.14.4',

  'gst-plugins-base-1.0-static' : '1.14.4',

  'gst-plugins-good-1.0' : '1.14.4',

  'gst-plugins-good-1.0-static' : '1.14.4',

  'gst-plugins-bad-1.0' : '1.14.4',

  'gst-plugins-bad-1.0-static' : '1.14.4',

  'gst-plugins-ugly-1.0' : '1.14.4',

  'gst-plugins-ugly-1.0-static' : '1.14.4',

  'gst-libav-1.0' : '1.14.4',

  'gst-libav-1.0-static' : '1.14.4',

  'gst-rtsp-server-1.0' : '1.14.4',

  'gst-rtsp-server-1.0-static' : '1.14.4',

}

and I pulled the cerbero 1.14 branch using:

git clone https://github.com/GStreamer/cerbero

cd cerbero

git checkout 1.14

cerbero bootstrap

cerbero package gstreamer-1.0

I have set my path variables in .bashrc:

alias cerbero='~/cerbero/cerbero-uninstalled'

export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/opt/gstreamer/lib

export PATH=/opt/gstreamer/bin:$PATH

export GST_PLUGIN_PATH=/opt/gstreamer/lib/gstreamer-1.0/

export GI_TYPELIB_PATH=/opt/gstreamer/lib/girepository-1.0/

export PYTHONPATH=$PYTHONPATH:/usr/lib/python3/dist-packages/

export PYTHONPATH=$PYTHONPATH:/opt/gstreamer/lib/

I have also enabled introspection in plugins-bad by adding:

--enable-introspection

to the recipe file in cerbero
Here is what I am trying to run:
https://github.com/centricular/gstwebrtc-demos

Has anyone been able to compile and use the webrtc module on a raspberry pi? How can I further debug?

I am on a raspberry pi 3 b+ running raspbian and python 3.6

EDIT: This has been posted to the raspberry pi stack exchange. I dont have enough reputation to close it there and move it to stack overflow.

I have also compiled it using cerbero for the latest master version (1.15) by disabling gl in the plugins base. I still receive the same errors. If anyone can point me in the right direction, I am stuck here.

Answer is here:

https://www.reddit.com/r/raspberry_pi/comments/aatetl/has_anyone_been_able_to_run_gstreamers_webrtcbin/

you essentially have to remove the python3-gi and python3-gobject packages then install them via pip. Afterwards you have to replace the systems libffi with the one you built using cerbero.