--TEST-- igbinary and large arrays --FILE-- prop = $value; } public function __sleep() { return null; } } var_dump(bin2hex($s = igbinary_serialize(new BadSleep('override')))); var_dump(igbinary_unserialize($s)); ?> --EXPECTF-- Notice: igbinary_serialize(): __sleep should return an array only containing the names of instance-variables to serialize in %s on line %d string(32) "000000021708426164536c6565701400" object(BadSleep)#1 (1) { ["prop"]=> string(1) "x" }