Source

File: wp-includes/functions.php

function do_feed_rss2( $for_comments ) {
	if ( $for_comments ) {
		load_template( ABSPATH . WPINC . '/feed-rss2-comments.php' );
	} else {
		load_template( ABSPATH . WPINC . '/feed-rss2.php' );
	}
}