commit 43d4c0329e2348540a3a16ac61b3032f04eefd34
author Xiang Zhang <angwerzx@126.com> Wed May 17 22:03:35 2017 +0800
committer GitHub <noreply@github.com> Wed May 17 22:03:35 2017 +0800
tree e627eacc7a4d2678e9a248d6c506009b9cabc010
parent b769c91c2db304db44cd514344369cde1f8d9dc5

bpo-30301: Fix AttributeError when using SimpleQueue.empty() (#1601) (#1628)

Under *spawn* and *forkserver* start methods, SimpleQueue.empty() could
raise AttributeError due to not setting _poll in __setstate__.

Lib/multiprocessing/queues.py

diff --git a/Lib/multiprocessing/queues.py b/Lib/multiprocessing/queues.py
index dda03dd..a4f4ef8 100644
--- a/Lib/multiprocessing/queues.py
+++ b/Lib/multiprocessing/queues.py
@@ -337,6 +337,7 @@
 
     def __setstate__(self, state):
         (self._reader, self._writer, self._rlock, self._wlock) = state
+        self._poll = self._reader.poll
 
     def get(self):
         with self._rlock: