Issue #9501: Improved shutdown handling to deal with module attributes correctly.

diff --git a/Lib/logging/__init__.py b/Lib/logging/__init__.py
index e53718d745773d1b61871ecca74723896217d491..1a622a3d074778eba4a8e105f165161975834e3c 100644 (file)
--- a/Lib/logging/__init__.py
+++ b/Lib/logging/__init__.py
@@ -624,7 +624,8 @@ def _removeHandlerRef(wr):
     # This function can be called during module teardown, when globals are
     # set to None. If _acquireLock is None, assume this is the case and do
     # nothing.
-    if _acquireLock is not None:
+    if (_acquireLock is not None and _handlerList is not None and
+        _releaseLock is not None):
         _acquireLock()
         try:
             if wr in _handlerList: