Xcode 3.2 breakpoints error message

I'm writing a C++ program in Xcode 3.2 for CS106B and I've started getting this error message output to the console window:

Wed Aug  3 15:46:44 cljs-macbook-pro-17.local StanfordCS106BAssignment2[3543] <Error>:   
kCGErrorIllegalArgument: CGSDeviceUnlock: Invalid device lock
Wed Aug  3 15:46:44 cljs-macbook-pro-17.local StanfordCS106BAssignment2[3543] <Error>: 
kCGErrorFailure: Set a breakpoint @ CGErrorBreakpoint() to catch errors as they are logged.

I think I must have done something with breakpoints that the compiler doesn't like for some reason, but I'm not sure what. Is there any way to get it to st开发者_开发问答op doing that?

It looks like a bug in the graphics library. Quick fix is to put a WaitForMouseDown() right after you redraw the display if it is causing it to crash. I tried just using sleep for a few milliseconds, but that didn't seem to do it.