(gdb) bt full
#0  0x00000037e806e1f3 in _int_free () from /lib64/libc.so.6
No symbol table info available.
#1  0x00000037e8071fac in free () from /lib64/libc.so.6
No symbol table info available.
#2  0x000000000046b7b7 in ast_frame_free (fr=0x1b9da4b0, cache=0)
    at frame.c:369
No locals.
#3  0x00002aaab1173573 in mixmonitor_thread (obj=0x1bb08220)
   from /usr/lib/asterisk/modules/app_mixmonitor.so
        next = (struct ast_frame *) 0x0
        write = 1
        mixmonitor = (struct mixmonitor *) 0x1bb08220
        f = (struct ast_frame *) 0x1b9da4b0
        fs = (struct ast_filestream *) 0x2aaac80f3b70
        oflags = 577
        ext = 0x1bb08466 "wav49"
        errflag = 0
        __PRETTY_FUNCTION__ = "mixmonitor_thread"
#4  0x00000000004d4b8f in dummy_start (data=0x1b949260) at utils.c:806
        __cancel_buf = {__cancel_jmp_buf = {{__cancel_jmp_buf = {0,
        1063351100855877176, 0, 1094138176, 1080131584, 1094136400,
        1063351100855877496, 1063351101953312135}, __mask_was_saved = 0}},
  __pad = {0x413731c0, 0x0, 0x1b8f6dd0, 0x1b8f6dd0}}
---Type <return> to continue, or q <return> to quit---
        __cancel_routine = (void (*)(void *)) 0x426a2b <ast_unregister_thread>
        __cancel_arg = (void *) 0x41373940
        not_first_call = 0
        ret = (void *) 0x37e8344898
        a = {start_routine = 0x2aaab117330d <mixmonitor_thread>,
  data = 0x1bb08220,
  name = 0x1b892880 "mixmonitor_thread    started at [  301] app_mixmonitor.c launch_monitor_thread()"}
        lock_info = (struct thr_lock_info *) 0x1ba87c20
#5  0x00000037e8c061b5 in start_thread () from /lib64/libpthread.so.0
No symbol table info available.
#6  0x00000037e80cd36d in clone () from /lib64/libc.so.6
No symbol table info available.
#7  0x0000000000000000 in ?? ()
No symbol table info available.
(gdb)