[Python-Dev] Preventing recursion core dumps (original) (raw)

Guido van Rossum guido@beopen.com
Fri, 11 Aug 2000 09:28:09 -0500

> It seems better to tune the generic check than to special-case str, > repr, and getattr.

Right. This would be a step forward, at least for recursive Python code (which is the most common complaint). Reducing the current value by half, i.e. setting MAXRECURSIONDEPTH = 5000 works for me (Linux & AIX) Agreement on 5000?

No, the getattr example still dumps core for me. With 4000 it is fine, but this indicates that this is totally the wrong approach: I can change the available stack size with ulimit -s and cause a core dump anyway. Or there could be a loger path through the C code where more C stack is used per recursion.

We could set the maximum to 1000 and assume a "reasonable" stack size, but that doesn't make me feel comfortable either.

It would be good if there was a way to sense the remaining available stack, even if it wasn't portable. Any Linux experts out there?

Doesn't solve the problem for C code (extensions) though...

That wasn't what started this thread. Bugs in extensions are just that.

--Guido van Rossum (home page: http://www.pythonlabs.com/~guido/)