diff --git a/Objects/unicodeobject.c b/Objects/unicodeobject.c
index 6c8fe2d..f61f9d0 100644
--- a/Objects/unicodeobject.c
+++ b/Objects/unicodeobject.c
@@ -14167,6 +14167,12 @@
 
     PyType_Ready(&EncodingMapType);
 
+    if (PyType_Ready(&PyFieldNameIter_Type) < 0)
+        Py_FatalError("Can't initialize field name iterator type");
+
+    if (PyType_Ready(&PyFormatterIter_Type) < 0)
+        Py_FatalError("Can't initialize formatter iter type");
+
 #ifdef HAVE_MBCS
     winver.dwOSVersionInfoSize = sizeof(winver);
     if (!GetVersionEx((OSVERSIONINFO*)&winver)) {