3v4l.org

run code in 300+ PHP versions simultaneously
<?php class a { protected $a = 10; protected $c;} class b { protected $b; public function setA($a){$this->b = $a;return $this;}} $q = (new b)->setA(new a); var_dump(unserialize(serialize($q), [true]));
Output for 7.0.0 - 7.0.20, 7.1.0 - 7.1.20, 7.2.0 - 7.2.33, 7.3.16 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
object(b)#3 (1) { ["b":protected]=> object(a)#4 (2) { ["a":protected]=> int(10) ["c":protected]=> NULL } }
Output for 5.5.24 - 5.5.35, 5.6.8 - 5.6.28
Warning: unserialize() expects exactly 1 parameter, 2 given in /in/aeVVt on line 9 bool(false)

preferences:
144.39 ms | 402 KiB | 183 Q