Index: src/wp-includes/link-template.php
===================================================================
--- src/wp-includes/link-template.php	(revision 40568)
+++ src/wp-includes/link-template.php	(working copy)
@@ -560,7 +560,7 @@
  * @param string $feed   Optional. Feed type. Default empty.
  */
 function the_feed_link( $anchor, $feed = '' ) {
-	$link = '<a href="' . esc_url( get_feed_link( $feed ) ) . '">' . $anchor . '</a>';
+	$link = '<a rel="alternate" type="' . esc_attr( feed_content_type( $feed ) ) . '" href="' . esc_url( get_feed_link( $feed ) ) . '">' . esc_html( $anchor ) . '</a>';
 
 	/**
 	 * Filters the feed link anchor tag.
@@ -699,7 +699,7 @@
 		$link_text = __('Comments Feed');
 	}
 
-	$link = '<a href="' . esc_url( $url ) . '">' . $link_text . '</a>';
+	$link = '<a rel="alternate" type="' . esc_attr( feed_content_type( $feed ) ) . '" href="' . esc_url( $url ) . '">' . esc_html( $link_text ) . '</a>';
 	/**
 	 * Filters the post comment feed link anchor tag.
 	 *