Not safe to lookup objc runtime data

Every now and then I start getting this error in the debugger constantly. Sometimes the debugger will flat out hang, some times it will pause for 开发者_Python百科a minute. This is just when stepping through all objective-c code.

Any thoughts on what might cause it? I just started using a static library, and I'm stepping through static-library code and it seems that may be aggravating it.

Could be that there is a malloc going on in a parallel thread. Check out this guys solution: http://www.fatcatsoftware.com/blog/2010/04