Message10895

Here's the relevant backing structure for subclasses in PyType:

    private Set<WeakReference<PyType>> subclasses = Generic.set();

Generic.set() in turn constructs the Set with a HashSet backing; synchronization is used on the subclasses for all usage of this set. So it would seem to be trivial to change this to using a LinkedHashSet instead to maintain original load order per Myles request to get the same behavior as CPython.

This code still will intersect with this other code I mentioned, but at least it's very much contained, with little to no risk I can see in making this change.