#0  0x00007fbd225a4095 in raise () from /lib/libc.so.6
#1  0x00007fbd225a5af0 in abort () from /lib/libc.so.6
#2  0x00007fbd225dea7b in ?? () from /lib/libc.so.6
#3  0x00007fbd225e608a in ?? () from /lib/libc.so.6
#4  0x00007fbd225e9c1c in free () from /lib/libc.so.6
#5  0x00007fbd225d4dac in fclose () from /lib/libc.so.6
#6  0x00000000004597fe in filestream_destructor (arg=0x1020318) at file.c:338
#7  0x000000000042c906 in ?? ()
#8  0x000000000045cc85 in ast_frame_free (fr=0x6024, cache=1) at frame.c:329
#9  0x00007fbd2236dd4a in moh_files_generator (chan=0x7fbcfc05b830, 
    data=<value optimized out>, len=<value optimized out>, 
    samples=<value optimized out>) at res_musiconhold.c:287
#10 0x000000000043f005 in generator_force (data=<value optimized out>)
    at channel.c:1619
#11 0x0000000000442a58 in __ast_read (chan=0x7fbcfc05b830, dropaudio=0)
    at channel.c:2100
#12 0x00000000004436d1 in ast_safe_sleep_conditional (chan=0x7fbcfc05b830, 
    ms=978, cond=0x7fbd168a64f0 <agent_cont_sleep>, data=0xaccad0)
    at channel.c:2434
#13 0x00007fbd168aaf42 in __login_exec (chan=0x7fbcfc05b830, 
    data=<value optimized out>, callbackmode=0) at chan_agent.c:2276
#14 0x00000000004836f8 in pbx_extension_helper (c=0x7fbcfc05b830, 
    con=<value optimized out>, context=0x7fbcfc05ba80 "default",
    exten=0x7fbcfc05bad0 "10", priority=11, label=<value optimized out>, 
    callerid=0x7fbcfc095570 "Estacion31", action=E_SPAWN) at pbx.c:537
#15 0x0000000000485068 in __ast_pbx_run (c=0x7fbcfc05b830) at pbx.c:2318
#16 0x0000000000485d29 in pbx_thread (data=0x6024) at pbx.c:2622
#17 0x00000000004b0cfc in dummy_start (data=<value optimized out>)
    at utils.c:856
#18 0x00007fbd22fac3f7 in start_thread () from /lib/libpthread.so.0
#19 0x00007fbd22649b3d in clone () from /lib/libc.so.6
#20 0x0000000000000000 in ?? ()
(gdb) down 6
#6  0x00000000004597fe in filestream_destructor (arg=0x1020318) at file.c:338
338     fclose(f->f);
(gdb) p f
$3 = <value optimized out>
(gdb) p *f
Cannot access memory at address 0x0