(gdb)                                                                                                                                                                  
(gdb) bt full                                                                                                                                                          
#0  0x00007fffedd57b40 in siptag_reason_str () from /usr/local/freeswitch/mod/mod_sofia.so                                                                              
No symbol table info available.                                                                                                                                        
#1  0x00007ffff72e40c4 in switch_core_session_hangup_state (session=session@entry=0x7fffc403af68, force=force@entry=SWITCH_TRUE) at src/switch_core_state_machine.c:852
        cause = <optimized out>                                                                                                                                        
        cause_q850 = <optimized out>                                                                                                                                    
        proceed = 1                                                                                                                                                    
        global_proceed = 1                                                                                                                                              
        index = 1                                                                                                                                                      
        state = CS_HANGUP                                                                                                                                              
        midstate = CS_HANGUP                                                                                                                                            
        endpoint_interface = <optimized out>                                                                                                                            
        driver_state_handler = 0x7fffedd61160 <sofia_event_handlers>                                                                                                    
        application_state_handler = <optimized out>                                                                                                                    
        hook_var = <optimized out>                                                                                                                                      
        use_session = 0                                                                                                                                                
        __func__ = "switch_core_session_hangup_state"                                                                                                                  
        __PRETTY_FUNCTION__ = "switch_core_session_hangup_state"                                                                                                        
#2  0x00007ffff72e5a35 in switch_core_session_run (session=0x7fffc403af68) at src/switch_core_state_machine.c:615
        global_proceed = 1
        index = 0
        proceed = 1
        do_extra_handlers = 1
        ptr = <optimized out>
        rstatus = <optimized out>
        state = <optimized out>
        midstate = <optimized out>
        endstate = <optimized out>
        endpoint_interface = <optimized out>
        driver_state_handler = <optimized out>
        application_state_handler = <optimized out>
        new_loops = 500
        __PRETTY_FUNCTION__ = "switch_core_session_run"
        __func__ = "switch_core_session_run"
#3  0x00007ffff72dfe5e in switch_core_session_thread (thread=<optimized out>, obj=0x7fffc403af68) at src/switch_core_session.c:1648
        session = 0x7fffc403af68
        event = 0x0
        event_str = 0x0
        val = <optimized out>
        __func__ = "switch_core_session_thread"
---Type <return> to continue, or q <return> to quit---
        __PRETTY_FUNCTION__ = "switch_core_session_thread"
#4  0x00007ffff72dbb53 in switch_core_session_thread_pool_worker (thread=0x7fffc405ac30, obj=<optimized out>) at src/switch_core_session.c:1711
        td = 0x7fffc4052100
        pop = 0x7fffc4052100
        check_status = <optimized out>
        node = <optimized out>
        pool = 0x7fffc405a9d8
        __func__ = "switch_core_session_thread_pool_worker"
#5  0x00007ffff7596210 in dummy_worker (opaque=0x7fffc405ac30) at threadproc/unix/thread.c:151
        thread = 0x7fffc405ac30
#6  0x00007ffff53a4e25 in start_thread () from /lib64/libpthread.so.0
No symbol table info available.
#7  0x00007ffff49ff34d in clone () from /lib64/libc.so.6

    No symbol table info available.