3v4l.org

run code in 300+ PHP versions simultaneously
<?php echo bin2hex(pack('P', PHP_INT_MAX - 128));
Output for 5.6.3 - 5.6.40, 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 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
7fffffffffffff7f
Output for 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.2
Warning: pack(): Type P: unknown format code in /in/fVSFF on line 3

preferences:
267.55 ms | 402 KiB | 375 Q