3v4l.org

run code in 300+ PHP versions simultaneously
<?php function foo(&$a) {$a[1] = 1;return $a;}; print_r(foo(array(1,2,3)));
Output for 8.3.0 - 8.3.6
Fatal error: Uncaught Error: foo(): Argument #1 ($a) could not be passed by reference in /in/cgSKe:3 Stack trace: #0 {main} thrown in /in/cgSKe on line 3
Process exited with code 255.
Output for 8.1.23 - 8.1.27, 8.2.10 - 8.2.18
Fatal error: Uncaught Error: foo(): Argument #1 ($a) cannot be passed by reference in /in/cgSKe:3 Stack trace: #0 {main} thrown in /in/cgSKe on line 3
Process exited with code 255.
Output for 5.3.0 - 5.3.27, 5.4.0 - 5.4.19
Fatal error: Only variables can be passed by reference in /in/QgcNK on line 3
Process exited with code 255.

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