diff --git a/typo3/sysext/core/Classes/Authentication/AbstractUserAuthentication.php b/typo3/sysext/core/Classes/Authentication/AbstractUserAuthentication.php
index 0c169ef8c79eeafdb2dac77c011dc0b2715ef7e7..dab73e90ecd53fed5ab0d79876aeba06896a47a4 100644
--- a/typo3/sysext/core/Classes/Authentication/AbstractUserAuthentication.php
+++ b/typo3/sysext/core/Classes/Authentication/AbstractUserAuthentication.php
@@ -345,6 +345,8 @@ abstract class AbstractUserAuthentication
      */
     public function __construct()
     {
+        // This function has to stay even if it's empty
+        // Implementations of that abstract class might call parent::__construct();
     }
 
     /**