loci: fix non-generated unused variable warnings
diff --git a/c_gen/c_code_gen.py b/c_gen/c_code_gen.py
index 4aec103..735dc6d 100644
--- a/c_gen/c_code_gen.py
+++ b/c_gen/c_code_gen.py
@@ -1108,8 +1108,10 @@
 static inline void
 of_object_parent_length_update(of_object_t *obj, int delta)
 {
+#ifndef NDEBUG
     int count = 0;
     of_wire_buffer_t *wbuf;  /* For debug asserts only */
+#endif
 
     while (obj != NULL) {
         ASSERT(count++ < _MAX_PARENT_ITERATIONS);
@@ -1117,7 +1119,9 @@
         if (obj->wire_length_set != NULL) {
             obj->wire_length_set(obj, obj->length);
         }
+#ifndef NDEBUG
         wbuf = obj->wire_object.wbuf;
+#endif
 
         /* Asserts for wire length checking */
         ASSERT(obj->length + obj->wire_object.obj_offset <=
diff --git a/c_gen/templates/of_type_maps.c b/c_gen/templates/of_type_maps.c
index ef1df37..f1fab57 100644
--- a/c_gen/templates/of_type_maps.c
+++ b/c_gen/templates/of_type_maps.c
@@ -50,8 +50,7 @@
 void
 of_object_message_wire_length_get(of_object_t *obj, int *bytes)
 {
-    of_wire_buffer_t *wbuf = OF_OBJECT_TO_WBUF(obj);
-    ASSERT(wbuf != NULL);
+    ASSERT(OF_OBJECT_TO_WBUF(obj) != NULL);
     // ASSERT(obj is message)
     *bytes = of_message_length_get(OF_OBJECT_TO_MESSAGE(obj));
 }
@@ -65,9 +64,7 @@
 void
 of_object_message_wire_length_set(of_object_t *obj, int bytes)
 {
-    of_wire_buffer_t *wbuf = OF_OBJECT_TO_WBUF(obj);
-    ASSERT(wbuf != NULL);
-
+    ASSERT(OF_OBJECT_TO_WBUF(obj) != NULL);
     // ASSERT(obj is message)
     of_message_length_set(OF_OBJECT_TO_MESSAGE(obj), bytes);
 }