diff --git a/backup/util/xml/parser/progressive_parser.class.php b/backup/util/xml/parser/progressive_parser.class.php
index 91bc85fc4b2d2..d465aba9d42be 100644
--- a/backup/util/xml/parser/progressive_parser.class.php
+++ b/backup/util/xml/parser/progressive_parser.class.php
@@ -278,6 +278,6 @@ protected function char_data($parser, $data) {
 class progressive_parser_exception extends moodle_exception {
 
     public function __construct($errorcode, $a=NULL, $debuginfo=null) {
-        parent::__construct($errorcode, 'error', '', $a, null, $debuginfo);
+        parent::__construct($errorcode, 'error', '', $a, $debuginfo);
     }
 }