diff --git a/openflow_input/standard-1.3 b/openflow_input/standard-1.3
index ed2610b..7a58b60 100644
--- a/openflow_input/standard-1.3
+++ b/openflow_input/standard-1.3
@@ -569,7 +569,7 @@
 };
 
 struct of_hello_elem {
-    uint16_t type;
+    uint16_t type == ?;
     uint16_t length;
 };