3v4l.org

run code in 500+ PHP versions simultaneously
<?php function foo(&$a){} foo(($a=1));
Output for 8.3.0 - 8.3.30, 8.4.1 - 8.4.18, 8.5.0 - 8.5.3
Fatal error: Uncaught Error: foo(): Argument #1 ($a) could not be passed by reference in /in/8hVVK:6 Stack trace: #0 {main} thrown in /in/8hVVK on line 6
Process exited with code 255.
Output for 8.0.0 - 8.0.30, 8.1.0 - 8.1.34, 8.2.0 - 8.2.30
Fatal error: Uncaught Error: foo(): Argument #1 ($a) cannot be passed by reference in /in/8hVVK:6 Stack trace: #0 {main} thrown in /in/8hVVK on line 6
Process exited with code 255.
Output for 7.3.0 - 7.3.33, 7.4.0 - 7.4.33
Notice: Only variables should be passed by reference in /in/8hVVK on line 6

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