[pypy-dev] spotting pypy segfault

[Maciej Fijalkowski]

Argh! I think I know how that happened. Suppose we have a cycle, which
allocates n bytes on each cycle. So on each iteration we check if
stack is at least size of n. But let's suppose we have somewhere along
the cycle path of length m > n which returns. It means that our stack
check might not catch it since we have n bytes left. But we actually
need m, boom.
(Traceback resembles a bit this situation, on the very top is stuff
that is slightly different than repeating pattern).

Cheers,
fijal