There is a memory leak in the new dictionary resizing in 3.6, which can cause memory exhaustion in just a few iterations.

I don't fully understand the details of the bug, but it happens when resizing a dict with a split table several times.  The only way that I have found to trigger this is by popping items off of an object's `__dict__` repeatedly.

I've attached a script to illustrate the issue. Be careful with it, because it will eat up all your memory if you don't interrupt it.