3v4l.org

run code in 300+ PHP versions simultaneously
<?php function& test(&$arr = array()) { $GLOBALS['g_arr'] =& $arr; $arr[] = 1; var_dump($arr); } test(); var_dump($g_arr);
Output for 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.20, 7.2.0 - 7.2.33, 7.3.12 - 7.3.31, 7.4.0 - 7.4.25, 7.4.27 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.27, 8.2.0 - 8.2.17, 8.3.0 - 8.3.4
array(1) { [0]=> int(1) } Notice: Only variable references should be returned by reference in /in/2A5gM on line 6 array(1) { [0]=> int(1) }
Output for 7.3.32 - 7.3.33, 7.4.26
array(1) { [0]=> int(1) } array(1) { [0]=> int(1) }
Output for 5.0.0 - 5.0.5
array(1) { [0]=> int(1) } Strict Standards: Only variable references should be returned by reference in /in/2A5gM on line 6 array(1) { [0]=> int(1) }
Output for 4.4.2 - 4.4.9
Parse error: syntax error, unexpected '=', expecting ')' in /in/2A5gM on line 2
Process exited with code 255.
Output for 4.3.0 - 4.3.1, 4.3.5 - 4.3.11, 4.4.0 - 4.4.1
Parse error: parse error, unexpected '=', expecting ')' in /in/2A5gM on line 2
Process exited with code 255.
Output for 4.3.2 - 4.3.4
Parse error: parse error, expecting `')'' in /in/2A5gM on line 2
Process exited with code 255.

preferences:
259.84 ms | 401 KiB | 352 Q