3v4l.org

run code in 300+ PHP versions simultaneously
<?php $_SESSION['var'] = 1; function func1() { global $ref; global $nonRef; $ref = &$_SESSION['var']; $nonRef = $_SESSION['var']; } func1(); var_dump($_SESSION['var']); var_dump($ref); var_dump($nonRef);
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.40, 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.30, 8.0.0 - 8.0.23, 8.1.0 - 8.1.10
int(1) NULL int(1)

preferences:
67.73 ms | 412 KiB | 5 Q