#0  0x00007f0cac4c31b5 in raise () from /lib/libc.so.6
#1  0x00007f0cac4c5fc0 in abort () from /lib/libc.so.6
#2  0x00007f0cac4bc301 in __assert_fail () from /lib/libc.so.6
#3  0x00007f0cad50fe09 in __pthread_mutex_lock_full ()
   from /lib/libpthread.so.0
#4  0x000000000046d1b8 in boost::asio::detail::posix_mutex::lock (
    this=0xbcf04028) at /usr/include/boost/asio/detail/posix_mutex.hpp:71
#5  0x0000000000470c54 in scoped_lock (this=0x7f0ca92c5340, m=...)
    at /usr/include/boost/asio/detail/scoped_lock.hpp:36
#6  0x0000000000489381 in boost::asio::detail::task_io_service<boost::asio::detail::epoll_reactor<false> >::post<boost::asio::detail::binder1<boost::_bi::bind_t<void, void (*)(boost::weak_ptr<Connection>, boost::system::error_code const&), boost::_bi::list2<boost::_bi::value<boost::weak_ptr<Connection> >, boost::arg<1> (*)()> >, boost::system::error_code> > (this=0xbcf04000, handler=...)
    at /usr/include/boost/asio/detail/task_io_service.hpp:192
#7  0x0000000000487622 in boost::asio::io_service::post<boost::asio::detail::binder1<boost::_bi::bind_t<void, void (*)(boost::weak_ptr<Connection>, boost::system::error_code const&), boost::_bi::list2<boost::_bi::value<boost::weak_ptr<Connection> >, boost::arg<1> (*)()> >, boost::system::error_code> > (
    this=0x7fffc9b98a57, handler=...)
    at /usr/include/boost/asio/impl/io_service.ipp:136
#8  0x0000000000485797 in boost::asio::detail::deadline_timer_service<boost::asio::time_traits<boost::posix_time::ptime>, boost::asio::detail::epoll_reactor<fal---Type <return> to continue, or q <return> to quit---q