Hangup error?

I have an issue with my code crashing. I know what the problem is or the general direction(assigning out of bounds in an array i believe) to start investigating just by some of the symptoms i am having. On top of the symptoms, when the mud crashes i get this error message:

4 [sig] smaug 2340 d:\smaugstuff\fuss18 smaug\src\smaug.exe: *** fatal error - called with threadlist_ix -1
Hangup

Just wondering if this message is supposed to mean anything in particular? To give me another clue to the puzzle

If you know the problem is an out of bounds assignment, you should probably start by checking all the code you just added having to do with array usage.

If that doesn't help, I suggest running the game through the debugger gdb. Nick Gammon wrote an excellent guide here: http://www.gammon.com.au/forum/bbshowpost.php?bbsubject_id=3653

i knew what code caused the problem - something i coded last year... i was able to fix it fairly quickly but I was just wondering if anyone knew what the hangup message meant exactly.