Index: Lib/test/test_weakref.py
===================================================================
--- Lib/test/test_weakref.py	(révision 66336)
+++ Lib/test/test_weakref.py	(copie de travail)
@@ -665,7 +665,15 @@
 
         w = Target()
 
+    def test_init(self):
+        # Issue 3634
+        # <weakref to class>.__init__() doesn't check errors correctly
+        r = weakref.ref(Exception)
+        self.assertRaises(TypeError, r.__init__, 0, 0, 0, 0, 0)
+        # No exception should be raised here
+        gc.collect()
 
+
 class SubclassableWeakrefTestCase(TestBase):
 
     def test_subclass_refs(self):