Joomla Error :: Warning: Parameter 1 to modMainMenuHelper::buildXML()

[Connor]

Hello,
I have recently upgraded PHP and MySQL. Joomla doesn't show the menu after upgrading PHP and MySQL and throwing following warning message:

Warning: Parameter 1 to modMainMenuHelper::buildXML() expected to be a reference, value
Joomla does not show the menu after upgrading PHP and mysql to 5.3 and 5.1 replies.

[KelvinSmith]

Open the file mentioned below.

[root@checker ~]#vi modules/mod_mainmenu/helper.php

Replace

function buildXML(&$params)

With

function buildXML($params)

and save it.