unset($this) causes a fatal error in PHP7.1

[nicolasreich]

Starting from PHP7.1, unset($this) causes a fatal error (see the PHP RFC). There are two instances (I think), in core/IDP.php:230 and in core/AbstractProfile.php:360.

[restena-sw]

See commit message for details of the fix.
Related: we are currently developing against PHP 7.0 as a baseline. In fact I tried an early patchlevel of 7.1 but the script execution went into erratic ways that our code can't possibly trigger. So I suspected a PHP 7.1 bug and stayed away from 7.1.
If recent 7.1 works for you, please do let us know and we can think about upping the baseline before release.

[nicolasreich]

Yes the parts I'm using work with 7.1. I'm mostly using the installer generation part though, not the front-end, not the CA part, not the database part,... so I can't know if it breaks something there. But the installer generation thing does work yes.

[restena-sw]

The break was when rendering the frontend's index.php.