https://github.com/stuttter/ludicrousdb/blob/master/ludicrousdb/includes/class-ludicrousdb.php#L692

public function db_connect( $query = '' ) {

vs WP core since 3.9.0
https://github.com/WordPress/wordpress-develop/blob/trunk/src/wp-includes/class-wpdb.php#L1948

public function db_connect( $allow_bail = true ) {

This leads to unexpected behavior and a PHP notice when ludicrousdb is used as drop-in, since plulgins might pass bool explicitly.