dl("mysqli") fails when OPcache is enabled #8508

Description

The following code:

<?php
dl("mysqli");

Resulted in this output:

Fatal error: Internal zvals cannot be refcounted in Unknown on line 0

But I expected this output instead:

The problem is mysqli_exception::$sqlstate; its value "00000" won't would be interned, and so the respective check

This is particularly an issue regarding the tests, because as of PHP 8.1.0, run-tests.php tries to figure out which dynamic extension can be loaded to gather the $exts_to_tests; however, due to this issue the list is not complete, so when OPcache is enabled, about 2.000 tests are not executed on AppVeyor CI.

PHP Version

PHP-8.0

Operating System

Windows