diff --git a/Objects/object.c b/Objects/object.c
index a29c31a..b2c7c14 100644
--- a/Objects/object.c
+++ b/Objects/object.c
@@ -1265,9 +1265,11 @@
 		if (PyDict_Check(dict))
 			result = PyDict_Keys(dict);
 		else {
-			PyErr_Format(PyExc_TypeError,
-				     "%.200s.__dict__ is not a dictionary",
-				     PyModule_GetName(obj));
+			const char *name = PyModule_GetName(obj);
+			if (name)
+				PyErr_Format(PyExc_TypeError,
+					     "%.200s.__dict__ is not a dictionary",
+					     name);
 		}
 	}