diff --git a/Lib/threading.py b/Lib/threading.py
index eebe10a..b7b7023 100644
--- a/Lib/threading.py
+++ b/Lib/threading.py
@@ -535,7 +535,8 @@
                 # test_threading.test_no_refcycle_through_target when
                 # the exception keeps the target alive past when we
                 # assert that it's dead.
-                self.__exc_clear()
+                # XXX Temporary experiment
+                # self.__exc_clear()
         finally:
             with _active_limbo_lock:
                 self.__stop()