Without seeing code, it is hard to say much, but two possibilities for unlimited stack growth are

(1) constructor cycles: object A creates an object B, and oject B creates an object A. The memory would blow up at the first creation of object A or B.

(2) Some object or class method uses a recursive algorithm that isn't terminating.

In any case, I think you need to look at the code and trace through a run using print statments or the debugger to narrow it down further.