Well, it doesn't seem like a problem with spaces or anything like that, but rather some design problem. Stack overflow usually means infinite recursion - i.e. some function doesn't return as it should, but rather calls itself again (of course, it may not be direct, it could call some other code that ends up calling the original function). It may even possibly(?) be some inter-process thing, like your code being caught by avast!, redirected somewhere, intercepted by your code, caught by avast!, etc.... I'm afraid it's hard to say without stack inspection.
If you stop the program in debugger (and if you have the symbols for the compiled executable, which you probably do), doesn't the IDE show you the stack as source references? (i.e. is it really necessary to check it in ASM?)