Ticket #13657: 13657.3.diff

src/wp-includes/wp-db.php

@@ -3083 +3083 @@
          */
         public function bail( $message, $error_code = '500' ) {
                 if ( !$this->show_errors ) {
+                        $message .= mysql_error( $this->dbh );
                         if ( class_exists( 'WP_Error', false ) ) {
                                 $this->error = new WP_Error($error_code, $message);
                         } else {