GST_QUEUE2_CAST  2100 plugins/elements/gstqueue2.c   return gst_queue2_handle_src_query (GST_QUEUE2_CAST (element)->srcpad, query);
GST_QUEUE2_CAST  2110 plugins/elements/gstqueue2.c   queue = GST_QUEUE2_CAST (gst_pad_get_parent (pad));