svn+ssh://pythondev@svn.python.org/python/branches/py3k
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r83918 | antoine.pitrou | 2010-08-10 00:38:19 +0200 (mar., 10 août 2010) | 5 lines
Issue #3757: thread-local objects now support cyclic garbage collection.
Thread-local objects involved in reference cycles will be deallocated
timely by the cyclic GC, even if the underlying thread is still running.
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* Use try/except ImportError or test_support.import_module() to import thread
and threading modules
* Add @unittest.skipUnless(threading, ...) to testcases using threads
When a thread touches such an object for the first time, a new thread-local __dict__ is created,
and the __init__ method is run.
But a thread switch can occur here; if the other thread touches the same object, it installs another
__dict__; when the first thread resumes, it updates the dictionary of the second...
This is the deep cause of the failures in test_multiprocessing involving "managers" objects.
Also a 2.5 backport candidate.
Antoine Pitrou
Victor Stinner
Jack Diederich
Ezio Melotti
Philip Jenvey
Benjamin Peterson
Amaury Forgeot d'Arc
Christian Heimes
Collin Winter
Jim Fulton