Fixed a SIGSEGV issue when stopping oaisim.

git-svn-id: http://svn.eurecom.fr/openair4G/trunk@4684 818b1a75-f10b-46b9-bf7c-635c3b92a50f

common/utils/itti/intertask_interface_dump.c

@@ -772,12 +772,16 @@ static void itti_dump_user_data_delete_function(void *user_data, void *user_stat
         task_id_t task_id;
 
         item = (itti_dump_queue_item_t *)user_data;
-        task_id = ITTI_MSG_ORIGIN_ID(item->data);
 
         if (item->data != NULL)
         {
+            task_id = ITTI_MSG_ORIGIN_ID(item->data);
             itti_free(task_id, item->data);
         }
+        else
+        {
+            task_id = TASK_UNKNOWN;
+        }
         itti_free(task_id, item);
     }
 }