t@91 (l@91) terminated by signal SEGV (no mapping at the fault address)
0xfed1587c: strlen+0x000c:      movl     (%eax),%edx
Current function is ast_dynamic_str_thread_build_va
 1354           res = vsnprintf((*buf)->str + offset, (*buf)->len - offset, fmt, ap);
(dbx) where
current thread: t@91
  [1] strlen(0x0), at 0xfed1587c
  [2] _ndoprnt(0xfe8eb5aa, 0xfc5188e4, 0xfc518130, 0x0), at 0xfed6db66
  [3] vsnprintf(0x81fdbcc, 0xb8, 0xfe8eb55c, 0xfc5188e4, 0x81542b0, 0xfedbf000), at 0xfed70c9b
=>[4] ast_dynamic_str_thread_build_va(buf = 0xfc518178, max_len = 1024U, ts = 0x814a9a0, append = 0, fmt = 0xfe8eb55c "Feature interpret: chan=%s, peer=%s, code=%s, sense=%d, features=%d dynamic=%s\n", ap = 0xfc5188e4 "çÓ$^H^?Ë$^HÀ\x8aQü^A"), line 1354 in "utils.c"
  [5] ast_log(level = 0, file = 0xfe8ea4cd "res_features.c", line = 1147, function = 0xfe8ea2ab "ast_feature_interpret", fmt = 0xfe8eb55c "Feature interpret: chan=%s, peer=%s, code=%s, sense=%d, features=%d dynamic=%s\n", ...), line 807 in "logger.c"
  [6] ast_feature_interpret(chan = 0x827bc10, peer = 0x826a3b0, config = 0xfc518d50, code = 0xfc518ac0 "1", sense = 1), line 1147 in "res_features.c"
  [7] ast_bridge_call(chan = 0x827bc10, peer = 0x826a3b0, config = 0xfc518d50), line 1626 in "res_features.c"
  [8] dial_exec_full(chan = 0x827bc10, data = 0xfc51bbe0, peerflags = 0xfc519af4, continue_exec = (nil)), line 1780 in "app_dial.c"
  [9] dial_exec(chan = (nil), data = (nil)), line 1834 in "app_dial.c"
  [10] pbx_extension_helper(c = (nil), con = 0xfc51de18, context = 0x827bd90 "outbound_nextra", exten = 0x827bde0 "421912345678", priority = 7, label = (nil), callerid = 0x81751f8 "421212345678", action = E_SPAWN), line 35 in "strings.h"
  [11] __ast_pbx_run(c = (nil)), line 2317 in "pbx.c"
  [12] pbx_thread(data = (nil)), line 2621 in "pbx.c"
  [13] dummy_start(data = (nil)), line 912 in "utils.c"
  [14] _thr_setup(0xfec6ba00), at 0xfed944c7
  [15] _lwp_start(0x0, 0xb8, 0xfc5181bc, 0xfedbf000, 0xfc518114, 0x0), at 0xfed947b0
(dbx) threads
      t@1  a  l@1   ?()   LWP suspended in  __pollsys()
      t@3  a  l@3   dummy_start()   LWP suspended in  __pollsys()
      t@4  a  l@4   dummy_start()   sleep on 0x8150a20  in  __lwp_park()
      t@5  a  l@5   dummy_start()   LWP suspended in  __pollsys()
      t@6  a  l@6   dummy_start()   sleep on 0x818d7cc  in  __lwp_park()
      t@7  a  l@7   dummy_start()   sleep on 0x818e90c  in  __lwp_park()
      t@8  a  l@8   dummy_start()   sleep on 0x818fa4c  in  __lwp_park()
      t@9  a  l@9   dummy_start()   sleep on 0x8190b8c  in  __lwp_park()
     t@10  a l@10   dummy_start()   sleep on 0x8191ccc  in  __lwp_park()
     t@11  a l@11   dummy_start()   sleep on 0x8192e0c  in  __lwp_park()
     t@12  a l@12   dummy_start()   sleep on 0x81da874  in  __lwp_park()
     t@13  a l@13   dummy_start()   sleep on 0x81db95c  in  __lwp_park()
     t@14  a l@14   dummy_start()   sleep on 0x81dca44  in  __lwp_park()
     t@15  a l@15   dummy_start()   sleep on 0x81ddb2c  in  __lwp_park()
     t@16  a l@16   dummy_start()   LWP suspended in  __lwp_park()
     t@17  a l@17   dummy_start()   LWP suspended in  __lwp_unpark()
     t@18  a l@18   dummy_start()   LWP suspended in  __pollsys()
     t@19  a l@19   dummy_start()   LWP suspended in  ___nanosleep()
     t@20  a l@20   dummy_start()   sleep on 0xfd925420  in  __lwp_park()
     t@22  a l@22   dummy_start()   sleep on 0x8150840  in  __lwp_park()
     t@87  a l@87   dummy_start()   LWP suspended in  __pollsys()
     t@89  a l@89   dummy_start()   LWP suspended in  __pollsys()
o>   t@91  a l@91   dummy_start()   signal SIGSEGV in  strlen()
(dbx) thread -info t@91
        Thread t@91 (0xfec6ba00) at priority 0
        state: active on   l@91
        base function: 0x80f03b4: dummy_start() stack: 0xfc51e000[245760]
        flags: DETACHED|SUSPENDED
        masked signals: HUP INT PIPE TERM WINCH
        Currently active in strlen