Fix and test for an infinite C recursion.

Lib/test/test_builtin.py

@@ -649,6 +649,10 @@ class BuiltinTest(unittest.TestCase):
             def __hash__(self):
                 return 2**100
         self.assertEquals(type(hash(Y())), int)
+        class Z(long):
+            def __hash__(self):
+                return self
+        self.assertEquals(hash(Z(42)), hash(42L))
 
     def test_hex(self):
         self.assertEqual(hex(16), '0x10')

Objects/typeobject.c

@@ -4560,7 +4560,7 @@ slot_tp_hash(PyObject *self)
 		if (res == NULL)
 			return -1;
 		if (PyLong_Check(res))
-			h = res->ob_type->tp_hash(res);
+			h = PyLong_Type.tp_hash(res);
 		else
 			h = PyInt_AsLong(res);
 		Py_DECREF(res);