Program received signal SIGSEGV, Segmentation fault.
0x00000000005a57e8 in TclOODeleteChain (callPtr=0x0)
    at
153	    if (--callPtr->refCount >= 1) {
(gdb) bt
#0  0x00000000005a57e8 in TclOODeleteChain (callPtr=0x0)
    at
#1  0x000000000059edc4 in ReleaseClassContents (interp=0x8daef8, oPtr=0x9bdce8)
    at
#2  0x000000000059e5a9 in ObjectRenamedTrace (clientData=0x9bdce8,
    interp=0x8daef8, oldName=0x9b6108 "::C", newName=0x0, flags=16512)
    at
#3  0x00000000004131f7 in CallCommandTraces (iPtr=0x8daef8, cmdPtr=0x9c32b8,
    oldName=0x9b6108 "::C", newName=0x0, flags=16512)
    at
#4  0x0000000000412e32 in Tcl_DeleteCommandFromToken (interp=0x8daef8,
    cmd=0x9c32b8) at
#5  0x0000000000545426 in TclTeardownNamespace (nsPtr=0x904838)
    at
#6  0x0000000000410c47 in DeleteInterpProc (interp=0x8daef8)
    at
#7  0x000000000055ebe8 in Tcl_EventuallyFree (clientData=0x8daef8,
    freeProc=0x410a8a <DeleteInterpProc>)
    at
#8  0x0000000000410a88 in Tcl_DeleteInterp (interp=0x8daef8)
    at
#9  0x000000000051ca34 in SlaveObjCmdDeleteProc (clientData=0x8daef8)
    at
#10 0x0000000000412f2d in Tcl_DeleteCommandFromToken (interp=0x822648,
    cmd=0x996d08) at