Issue #11603: Fix a crash when __str__ is rebound as __repr__.
Patch by Andreas Stührk.
diff --git a/Lib/test/test_descr.py b/Lib/test/test_descr.py
index b5d9890..964cc5c 100644
--- a/Lib/test/test_descr.py
+++ b/Lib/test/test_descr.py
@@ -4581,6 +4581,14 @@
         with self.assertRaises(TypeError):
             str.__add__(fake_str, "abc")
 
+    def test_repr_as_str(self):
+        # Issue #11603: crash or infinite loop when rebinding __str__ as
+        # __repr__.
+        class Foo(object):
+            pass
+        Foo.__repr__ = Foo.__str__
+        foo = Foo()
+        str(foo)
 
 class DictProxyTests(unittest.TestCase):
     def setUp(self):