Edit File: spl-autoload-compat.php
<?php /** * Polyfill for SPL autoload feature. This file is separate to prevent compiler notices * on the deprecated __autoload() function. * * See https://core.trac.wordpress.org/ticket/41134 * * @deprecated 5.3.0 No longer needed as the minimum PHP requirement has moved beyond PHP 5.3. * * @package PHP * @access private */ _deprecated_file( basename( __FILE__ ), '5.3.0', '', 'SPL can no longer be disabled as of PHP 5.3.' );