#0  0x00007f97fd90661c in _sip_tcp_helper_thread (pvt=0x0, tcptls_session=0x0)
    at chan_sip.c:2715
#1  0x00007f97fd90533a in sip_tcp_worker_fn (data=0x7f97e22becb8)
    at chan_sip.c:2426
#2  0x0000000000559166 in dummy_start (data=0x7f97e22bc7c0) at utils.c:971
#3  0x00007f980711a8ba in start_thread () from /lib/libpthread.so.0
#4  0x00007f980795302d in clone () from /lib/libc.so.6
#5  0x0000000000000000 in ?? ()