find_recursion_limit.py in trunk is broken: it fails with an
AttributeError while a RuntimeError is expected. This has appeared due
to the recent changes in recursion limit handling, but the problem is
deeper. As I explained on the ML, functions like PyDict_GetItem()
discard any exception that occur inside them, and return NULL instead.
The caller can then interpret the NULL as an "attribute missing" and
raise AttributeError.

The obvious quick fix is to replace "except RuntimeError" with "except
(RuntimeError, AttributeError)" in find_recursion_limit.py.