_mongoc_topology_description_check_compatible doesn't allow for unknown states
@@ -1797,7 +1797,7 @@ mongoc_topology_description_handle_ismaster (
}
/* Don't bother checking wire version compatibility if we already errored */
- if (!error || !error->code) {
+ if (ismaster_response && (!error || !error->code)) {
_mongoc_topology_description_check_compatible (topology);
}
_mongoc_topology_description_monitor_changed (prev_td, topology);
