Larry Hastings <la...@hastings.org> added the comment:
> We should do that for each singletons: > > * None (Py_None) > * True (Py_True) > * False (Py_False) > * Ellipsis (Py_Ellipsis) Aren't there a couple more lurking in the interpreter? E.g. empty tuple, empty frozenset. > That is exactly why I didn't propose a change to them. > The singletons still are refcounted as usual, > just that their ob_refcnt is ignored. > If they somehow reach 0, they just "resurrect" themselves > and ignore the regular collection behavior. That seems like a very good idea! They don't even need to "resurrect" themselves--we just ensure tp_dealloc is a no-op for those special values. If we do that, different threads and different interpreters can change ob_refcnt willy-nilly, there can be unsafe races between threads, the value could no longer make any sense--but as long as we never free the object, it's all totally fine. (Actually: tp_dealloc shouldn't be a no-op--it should add a million to the reference count for these special objects, to forestall future irrelevant calls to tp_dealloc.) This might have minor deleterious effects, e.g. sys.getrefcount() would return misleading results for such objects. I think that's acceptable. ---------- nosy: +larry _______________________________________ Python tracker <rep...@bugs.python.org> <https://bugs.python.org/issue39511> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
