Source

File: wp-includes/link-template.php

function get_comments_pagenum_link( $pagenum = 1, $max_page = 0 ) {
	global $wp_rewrite;

	$pagenum = (int) $pagenum;

	$result = get_permalink();

	if ( 'newest' === get_option( 'default_comments_page' ) ) {
		if ( $pagenum != $max_page ) {
			if ( $wp_rewrite->using_permalinks() ) {
				$result = user_trailingslashit( trailingslashit( $result ) . $wp_rewrite->comments_pagination_base . '-' . $pagenum, 'commentpaged' );
			} else {
				$result = add_query_arg( 'cpage', $pagenum, $result );
			}
		}
	} elseif ( $pagenum > 1 ) {
		if ( $wp_rewrite->using_permalinks() ) {
			$result = user_trailingslashit( trailingslashit( $result ) . $wp_rewrite->comments_pagination_base . '-' . $pagenum, 'commentpaged' );
		} else {
			$result = add_query_arg( 'cpage', $pagenum, $result );
		}
	}

	$result .= '#comments';

	/**
	 * Filters the comments page number link for the current request.
	 *
	 * @since 2.7.0
	 *
	 * @param string $result The comments page number link.
	 */
	return apply_filters( 'get_comments_pagenum_link', $result );
}