( ! ) Warning: Unsupported declare 'strict_types' in C:\wamp64\www\libs\phpspreadsheet\maennchen\zipstream-php\src\Bigint.php on line 2

( ! ) Fatal error: Default value for parameters with a class type hint can only be NULL in C:\wamp64\www\libs\phpspreadsheet\maennchen\zipstream-php\src\Bigint.php on line 20