--- a/mercurial/cext/parsers.c	Sat May 20 22:27:52 2017 -0700
+++ b/mercurial/cext/parsers.c	Sun May 21 13:31:27 2017 +0900
@@ -944,6 +944,8 @@
 	manifest_module_init(mod);
 	revlog_module_init(mod);
 
+	if (PyType_Ready(&dirstateTupleType) < 0)
+		return;
 	Py_INCREF(&dirstateTupleType);
 	PyModule_AddObject(mod, "dirstatetuple",
 			   (PyObject *)&dirstateTupleType);