Ticket #19198: 19198.diff

wp-includes/query.php

@@ -2388 +2388 @@
                 if ( 'any' == $post_type ) {
                         $exclude_post_types = '';
                         $in_search_post_types = get_post_types( array('exclude_from_search' => false) );
-                        if ( ! empty( $in_search_post_types ) )
-                                $where .= $wpdb->prepare(" AND $wpdb->posts.post_type IN ('" . join("', '", $in_search_post_types ) . "')");
+                        $post_types = empty($in_search_post_types) ? 'null' :
+                                "'" . join("', '", $in_search_post_types ) . "'";
+                        $where .= $wpdb->prepare(" AND $wpdb->posts.post_type IN ($post_types)");
                 } elseif ( !empty( $post_type ) && is_array( $post_type ) ) {
                         $where .= " AND $wpdb->posts.post_type IN ('" . join("', '", $post_type) . "')";
                 } elseif ( ! empty( $post_type ) ) {