diff --git a/Modules/_testcapimodule.c b/Modules/_testcapimodule.c
index 7e0e95c..0ed2111 100644
--- a/Modules/_testcapimodule.c
+++ b/Modules/_testcapimodule.c
@@ -1037,6 +1037,12 @@
 	CHECK_1_FORMAT("%lu", unsigned long);
 	CHECK_1_FORMAT("%zu", size_t);
 
+	/* "%lld" and "%llu" support added in Python 2.7. */
+#ifdef HAVE_LONG_LONG
+	CHECK_1_FORMAT("%llu", unsigned PY_LONG_LONG);
+	CHECK_1_FORMAT("%lld", PY_LONG_LONG);
+#endif
+
 	Py_RETURN_NONE;
 
  Fail: