Upgrade to PHP 7
PHP 7 stays available since 03 Dec 2015, in addition PHP website states
Support for PHP 5 has been discontinued since 10 Jan 2019.Please consider upgrading to 7.
I don't know if only this repo needs update to use PHP 7 or some upstream dependencies also need action, if the do I think we can create issues in relevant repos.
I will create separate issue about Xdebug and link this issue from there.