Ticket #28155: 28155.3.diff

src/wp-includes/wp-db.php

@@ -1325 +1325 @@
                 if ( $this->use_mysqli && $this->result instanceof mysqli_result ) {
                         mysqli_free_result( $this->result );
                         $this->result = null;
-
-                        // Clear out any results from a multi-query
-                        while ( mysqli_more_results( $this->dbh ) ) {
-                                mysqli_next_result( $this->dbh );
-                        }
+                        if ( empty( $this->dbh ) || !( $this->dbh instanceof mysqli ) )
+                                return; // Sanity check before using the handle
+                        while ( $this->dbh->more_results() )
+                                $this->dbh->next_result();
                 } else if ( is_resource( $this->result ) ) {
                         mysql_free_result( $this->result );
                 }