Issue #20532: Tests which use _testcapi now are marked as CPython only.
diff --git a/Lib/test/test_descr.py b/Lib/test/test_descr.py
index 15a3049..6f91842 100644
--- a/Lib/test/test_descr.py
+++ b/Lib/test/test_descr.py
@@ -2092,6 +2092,7 @@
             prop2 = property(fset=setter)
             self.assertEqual(prop2.__doc__, None)
 
+    @test_support.cpython_only
     def test_testcapi_no_segfault(self):
         # this segfaulted in 2.5b2
         try: