(gdb) bt
#0  Logger_start (s=0x21c5260, o=<value optimized out>)
    at emc/usr_intf/axis/extensions/emcmodule.cc:1944
#1  0x000000000041f0c7 in PyObject_Call ()
#2  0x00000000004a1b03 in PyEval_CallObjectWithKeywords ()
#3  0x00000000004d7d3d in ?? ()
#4  0x00007fc039a1a9ca in start_thread () from /lib/libpthread.so.0
#5  0x00007fc0388f3cdd in clone () from /lib/libc.so.6
#6  0x0000000000000000 in ?? ()
(gdb)