Issue #18418: After fork(), reinit all threads states, not only active ones.
Patch by A. Jesse Jiryu Davis.
diff --git a/Lib/test/test_threading.py b/Lib/test/test_threading.py
index ef04cd3..5a765f3 100644
--- a/Lib/test/test_threading.py
+++ b/Lib/test/test_threading.py
@@ -443,6 +443,29 @@
self.assertEqual(out, '')
self.assertEqual(err, '')
+ @unittest.skipUnless(hasattr(os, 'fork'), "needs os.fork()")
+ def test_is_alive_after_fork(self):
+ # Try hard to trigger #18418: is_alive() could sometimes be True on
+ # threads that vanished after a fork.
+ old_interval = sys.getcheckinterval()
+
+ # Make the bug more likely to manifest.
+ sys.setcheckinterval(10)
+
+ try:
+ for i in range(20):
+ t = threading.Thread(target=lambda: None)
+ t.start()
+ pid = os.fork()
+ if pid == 0:
+ os._exit(1 if t.is_alive() else 0)
+ else:
+ t.join()
+ pid, status = os.waitpid(pid, 0)
+ self.assertEqual(0, status)
+ finally:
+ sys.setcheckinterval(old_interval)
+
class ThreadJoinOnShutdown(BaseTestCase):
diff --git a/Lib/threading.py b/Lib/threading.py
index 225448b..72c8319 100644
--- a/Lib/threading.py
+++ b/Lib/threading.py
@@ -1220,7 +1220,7 @@
new_active = {}
current = current_thread()
with _active_limbo_lock:
- for thread in _active.itervalues():
+ for thread in _enumerate():
# Any lock/condition variable may be currently locked or in an
# invalid state, so we reinitialize them.
if hasattr(thread, '_reset_internal_locks'):
diff --git a/Misc/ACKS b/Misc/ACKS
index 6a06396..8977c02 100644
--- a/Misc/ACKS
+++ b/Misc/ACKS
@@ -230,6 +230,7 @@
Ben Darnell
Kushal Das
Jonathan Dasteel
+A. Jesse Jiryu Davis
John DeGood
Ned Deily
Vincent Delft
diff --git a/Misc/NEWS b/Misc/NEWS
index f7e9372..9544b3b 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -32,6 +32,9 @@
Library
-------
+- Issue #18418: After fork(), reinit all threads states, not only active ones.
+ Patch by A. Jesse Jiryu Davis.
+
- Issue #11973: Fix a problem in kevent. The flags and fflags fields are now
properly handled as unsigned.