* During cyclic garbage collection, attributes of extension types that
cannot create reference cycles due to their type (e.g. strings) are
- no longer considered for traversal or clearing.
+ no longer considered for traversal or clearing. This can reduce the
+ processing overhead when searching for or cleaning up reference cycles.
* Package compilation (i.e. ``__init__.py`` files) now works, starting
with Python 3.3.
Other changes
-------------
-* In Py3.4+, the Cython generator type uses ``tp_finalize()`` for cleanup
- instead of ``tp_del()``.
+* In Py3.4+, the Cython generator type uses ``tp_finalize()`` for safer
+ cleanup instead of ``tp_del()``.
0.19.2 (??)