3v4l.org

run code in 300+ PHP versions simultaneously
<?php $foo = new stdclass; $foo->pdo = new stdclass; $bar = $foo; var_dump($bar,$foo); $foo = null; var_dump($bar,$foo);
Output for 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, 5.5.24 - 5.5.35, 5.6.8 - 5.6.21, 7.0.0 - 7.0.20, 7.1.0 - 7.1.10, 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(stdClass)#1 (1) { ["pdo"]=> object(stdClass)#2 (0) { } } object(stdClass)#1 (1) { ["pdo"]=> object(stdClass)#2 (0) { } } object(stdClass)#1 (1) { ["pdo"]=> object(stdClass)#2 (0) { } } NULL
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9
object(stdClass)(1) { ["pdo"]=> object(stdClass)(0) { } } object(stdClass)(1) { ["pdo"]=> object(stdClass)(0) { } } object(stdClass)(1) { ["pdo"]=> object(stdClass)(0) { } } NULL

preferences:
225.19 ms | 402 KiB | 309 Q