Program received signal SIGSEGV, Segmentation fault.[Switching to Thread 147466 (LWP 31822)]0xb7f1b17d in pthread_mutex_lock () from /lib/libpthread.so.0(gdb) bt f#0 0xb7f1b17d in pthread_mutex_lock () from /lib/libpthread.so.0No symbol table info available.#1 0x0805f9ab in CriticalSection::enter (this=0x48) at CriticalSection.h:62No locals.#2 0x0805f997 in LockBase (this=0xb2dffd40, aCs=@0x48) at CriticalSection.h:113No locals.#3 0x080cbb16 in ClientManager::putUserOffline (this=0x0, aUser=@0xaf963660, quitHub=false) at ClientManager.cpp:263 l = {cs = @0x48}#4 0x080ba6ec in NmdcHub::clearUsers (this=0xb3654aa0) at NmdcHub.cpp:110 i = {_M_cur = 0xaf963658, _M_ht = 0xb3654b7c}#5 0x080c1384 in NmdcHub::on (this=0xb3654aa0, aLine=@0x8242ec8) at NmdcHub.cpp:711 l = {cs = @0xb3654b64}#6 0x080b5348 in Speaker<BufferedSocketListener>::fire<BufferedSocketListener::X<7>, std::string> (this=0xb3654bb8, type={<No data fields>}, p1=@0x8242ec8) at Speaker.h:51 i = {_M_current = 0x8e21a58} l = {cs = @0xb3654bd4}#7 0x080b50ed in BufferedSocket::fail (this=0xb3654bb8, aError=@0x8242ec8) at BufferedSocket.h:194No locals.#8 0x080b4e4f in BufferedSocket::run (this=0xb3654bb8) at BufferedSocket.cpp:409 t = BufferedSocket::DISCONNECT sendingFile = false#9 0x080b785c in Thread::starter (p=0xb3654c04) at Thread.h:139 t = (class Thread *) 0xb3654c04#10 0xb7f19cd2 in pthread_start_thread () from /lib/libpthread.so.0No symbol table info available.#11 0xb7f19e42 in pthread_start_thread_event () from /lib/libpthread.so.0No symbol table info available.#12 0xb773a4ea in clone () from /lib/libc.so.6No symbol table info available.(gdb)