3v4l.org

run code in 300+ PHP versions simultaneously
<?php x = 0; $a = array(&$x); $b = $a; $x = 2; unset($x); $b[1]++; $b[0]++; echo $a[0], ' ', $b[0];
Output for 4.4.2 - 4.4.9, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.32
Parse error: syntax error, unexpected '=' in /in/GmJEZ 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, 5.0.0 - 5.0.5
Parse error: parse error, unexpected '=' in /in/GmJEZ on line 2
Process exited with code 255.
Output for 4.3.2 - 4.3.4
Parse error: parse error in /in/GmJEZ on line 2
Process exited with code 255.
preferences:
222.31 ms | 1395 KiB | 123 Q