<?php
class a { protected $a = 10; protected $c;}
class b { protected $b; public function setA($a){$this->b = $a;return $this;}}
var_dump(unserialize(serialize((new b)->setA(new a)), true));
Fatal error: Uncaught TypeError: unserialize(): Argument #2 ($options) must be of type array, true given in /in/hcj5A:7
Stack trace:
#0 /in/hcj5A(7): unserialize('O:1:"b":1:{s:4:...', true)
#1 {main}
thrown in /in/hcj5A on line 7
Process exited with code 255.
Fatal error: Uncaught TypeError: unserialize(): Argument #2 ($options) must be of type array, bool given in /in/hcj5A:7
Stack trace:
#0 /in/hcj5A(7): unserialize('O:1:"b":1:{s:4:...', true)
#1 {main}
thrown in /in/hcj5A on line 7
Process exited with code 255.
Output for 7.3.16 - 7.3.33, 7.4.0 - 7.4.33
Warning: unserialize() expects parameter 2 to be array, bool given in /in/hcj5A on line 7
bool(false)