From d74ac82df9cda264c120379a41e7add5d64b9d01 Mon Sep 17 00:00:00 2001
From: Victor Stinner <victor.stinner@gmail.com>
Date: Tue, 4 Mar 2014 23:07:08 +0100
Subject: [PATCH] asyncio, Tulip issue 158: Task._step() now also sets self to
 None if an exception is raised.  self is set to None to break a reference
 cycle.

---
 Lib/asyncio/tasks.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Lib/asyncio/tasks.py b/Lib/asyncio/tasks.py
index 19fa654edb..0967e7e628 100644
--- a/Lib/asyncio/tasks.py
+++ b/Lib/asyncio/tasks.py
@@ -325,7 +325,7 @@ class Task(futures.Future):
                         'Task got bad yield: {!r}'.format(result)))
         finally:
             self.__class__._current_tasks.pop(self._loop)
-        self = None
+            self = None  # Needed to break cycles when an exception occurs.
 
     def _wakeup(self, future):
         try:
-- 
2.40.0