Undefined variable: vary_header and cache_control_header

Hi, I’ve faced with the following errors:

Notice: Undefined variable: vary_header in /var/www/html/wp-content/plugins/wp-super-cache/wp-cache.php on line 3460

Notice: Undefined variable: cache_control_header in /var/www/html/wp-content/plugins/wp-super-cache/wp-cache.php on line 3463

To reproduce set constants to empty string:

define('WPSC_VARY_HEADER', '');
define('WPSC_CACHE_CONTROL_HEADER', '');

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