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<?php $array = array ('backtrace', 'print'); array_walk($array, 'walk_callback', str_repeat("\0",4096)); function walk_callback($value, $key, $userdata) { if ($value == 'print') { print($userdata); exit("\n\n"); } elseif ($value == 'backtrace') { debug_backtrace(); if ($userdata !== str_repeat("\0",1024)) { die("won't get here, \$userdata is still clean until we return"); } } }
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.5, 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 - 7.1.25, 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 - 8.3.7
won't get here, $userdata is still clean until we return
preferences:
266.74 ms | 406 KiB | 371 Q