On Mon, Jun 1, 2015, at 11:33, Antoine Pitrou wrote: > On Mon, 1 Jun 2015 16:38:35 +0200 > Petr Viktorin <encu...@gmail.com> wrote: > > Hello, > > The new test_importlib.extension.test_loader is currently leaking > > references, (issue24268). There is a simple hack to stop this, but I'm > > inclined to not apply quick hacks and rather dig into the root cause. > > (It's a test module, the refleaks are relatively harmless.) > > > > The tests are based directly on the "xxlimited" example, > > xxlimited.Xxo, which exhibits the same bug -- it's just not tested. > > It's is caused by a combination of a few factors, but I'm not sure > > what's a bug and what's just undocumented behavior, so I'm asking for > > input to put me on the right track. > > Yes, the issue is really nasty. There are several situations to take > into account: > - derived heap type inherits from base heap type, both have custom > deallocs > - derived heap type inherits from base heap type, only one has > a custom dealloc > - derived heap type inherits from Python-defined class (the latter > having subtype_dealloc) > - derived heap type inherits from static type > - ... > > It is unreasonable to expect developers of C extensions come up with > the correct incantation (and ideally, they shouldn't have to think > about it at all). > > > The nice way out would be taking advantage of PEP 442: xxlimited.Xxo > > can ditch tp_dealloc in favor of tp_traverse and tp_finalize (the > > former of which it needs anyway to behave correctly). Unfortunately, > > tp_finalize is not available in the stable ABI (issue24345). I think > > it should be added; is it too late for 3.5? > > Well, but.... the stable ABI is supposed to be a subset of the API > that's safe to program against, regardless of the Python version (at > least from the point where the stable ABI was introduced). What happens > if you define a Py_tp_finalize and run your C extension type on a > pre-3.5 version? Do you get an error at definition time? A resource > leak? A crash? > > I don't get why Benjamin committed the change so quick.
I thought all the slots were supposed to be available through the stable ABI, since you need them to properly define c types. _______________________________________________ Python-Dev mailing list Python-Dev@python.org https://mail.python.org/mailman/listinfo/python-dev Unsubscribe: https://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
