diff -r c7c34916027a -r 177826044cd9 wp/wp-includes/feed-atom-comments.php
--- a/wp/wp-includes/feed-atom-comments.php	Mon Oct 14 18:06:33 2019 +0200
+++ b/wp/wp-includes/feed-atom-comments.php	Mon Oct 14 18:28:13 2019 +0200
@@ -5,8 +5,8 @@
  * @package WordPress
  */
 
-header('Content-Type: ' . feed_content_type('atom') . '; charset=' . get_option('blog_charset'), true);
-echo '<?xml version="1.0" encoding="' . get_option('blog_charset') . '" ?' . '>';
+header( 'Content-Type: ' . feed_content_type( 'atom' ) . '; charset=' . get_option( 'blog_charset' ), true );
+echo '<?xml version="1.0" encoding="' . get_option( 'blog_charset' ) . '" ?' . '>';
 
 /** This action is documented in wp-includes/feed-rss2.php */
 do_action( 'rss_tag_pre', 'atom-comments' );
@@ -27,37 +27,36 @@
 		do_action( 'atom_comments_ns' );
 	?>
 >
-	<title type="text"><?php
-		if ( is_singular() ) {
-			/* translators: Comments feed title. 1: Post title */
-			printf( ent2ncr( __( 'Comments on %s' ) ), get_the_title_rss() );
-		} elseif ( is_search() ) {
-			/* translators: Comments feed title. 1: Site name, 2: Search query */
-			printf( ent2ncr( __( 'Comments for %1$s searching on %2$s' ) ), get_bloginfo_rss( 'name' ), get_search_query() );
-		} else {
-			/* translators: Comments feed title. 1: Site name */
-			printf( ent2ncr( __( 'Comments for %s' ) ), get_wp_title_rss() );
-		}
-	?></title>
-	<subtitle type="text"><?php bloginfo_rss('description'); ?></subtitle>
+	<title type="text">
+	<?php
+	if ( is_singular() ) {
+		/* translators: Comments feed title. %s: Post title */
+		printf( ent2ncr( __( 'Comments on %s' ) ), get_the_title_rss() );
+	} elseif ( is_search() ) {
+		/* translators: Comments feed title. 1: Site name, 2: Search query */
+		printf( ent2ncr( __( 'Comments for %1$s searching on %2$s' ) ), get_bloginfo_rss( 'name' ), get_search_query() );
+	} else {
+		/* translators: Comments feed title. %s: Site name */
+		printf( ent2ncr( __( 'Comments for %s' ) ), get_wp_title_rss() );
+	}
+	?>
+	</title>
+	<subtitle type="text"><?php bloginfo_rss( 'description' ); ?></subtitle>
 
-	<updated><?php
-		$date = get_lastcommentmodified( 'GMT' );
-		echo $date ? mysql2date( 'Y-m-d\TH:i:s\Z', $date, false ) : date( 'Y-m-d\TH:i:s\Z' );
-	?></updated>
+	<updated><?php echo get_feed_build_date( 'Y-m-d\TH:i:s\Z' ); ?></updated>
 
 <?php if ( is_singular() ) { ?>
-	<link rel="alternate" type="<?php bloginfo_rss('html_type'); ?>" href="<?php comments_link_feed(); ?>" />
-	<link rel="self" type="application/atom+xml" href="<?php echo esc_url( get_post_comments_feed_link('', 'atom') ); ?>" />
-	<id><?php echo esc_url( get_post_comments_feed_link('', 'atom') ); ?></id>
-<?php } elseif (is_search()) { ?>
-	<link rel="alternate" type="<?php bloginfo_rss('html_type'); ?>" href="<?php echo home_url() . '?s=' . get_search_query(); ?>" />
-	<link rel="self" type="application/atom+xml" href="<?php echo get_search_comments_feed_link('', 'atom'); ?>" />
-	<id><?php echo get_search_comments_feed_link('', 'atom'); ?></id>
+	<link rel="alternate" type="<?php bloginfo_rss( 'html_type' ); ?>" href="<?php comments_link_feed(); ?>" />
+	<link rel="self" type="application/atom+xml" href="<?php echo esc_url( get_post_comments_feed_link( '', 'atom' ) ); ?>" />
+	<id><?php echo esc_url( get_post_comments_feed_link( '', 'atom' ) ); ?></id>
+<?php } elseif ( is_search() ) { ?>
+	<link rel="alternate" type="<?php bloginfo_rss( 'html_type' ); ?>" href="<?php echo home_url() . '?s=' . get_search_query(); ?>" />
+	<link rel="self" type="application/atom+xml" href="<?php echo get_search_comments_feed_link( '', 'atom' ); ?>" />
+	<id><?php echo get_search_comments_feed_link( '', 'atom' ); ?></id>
 <?php } else { ?>
-	<link rel="alternate" type="<?php bloginfo_rss('html_type'); ?>" href="<?php bloginfo_rss('url'); ?>" />
-	<link rel="self" type="application/atom+xml" href="<?php bloginfo_rss('comments_atom_url'); ?>" />
-	<id><?php bloginfo_rss('comments_atom_url'); ?></id>
+	<link rel="alternate" type="<?php bloginfo_rss( 'html_type' ); ?>" href="<?php bloginfo_rss( 'url' ); ?>" />
+	<link rel="self" type="application/atom+xml" href="<?php bloginfo_rss( 'comments_atom_url' ); ?>" />
+	<id><?php bloginfo_rss( 'comments_atom_url' ); ?></id>
 <?php } ?>
 <?php
 	/**
@@ -68,47 +67,58 @@
 	do_action( 'comments_atom_head' );
 ?>
 <?php
-if ( have_comments() ) : while ( have_comments() ) : the_comment();
-	$comment_post = $GLOBALS['post'] = get_post( $comment->comment_post_ID );
-?>
+if ( have_comments() ) :
+	while ( have_comments() ) :
+		the_comment();
+		$comment_post = $GLOBALS['post'] = get_post( $comment->comment_post_ID );
+		?>
 	<entry>
-		<title><?php
-			if ( !is_singular() ) {
-				$title = get_the_title($comment_post->ID);
-				/** This filter is documented in wp-includes/feed.php */
-				$title = apply_filters( 'the_title_rss', $title );
-				/* translators: Individual comment title. 1: Post title, 2: Comment author name */
-				printf(ent2ncr(__('Comment on %1$s by %2$s')), $title, get_comment_author_rss());
-			} else {
-				/* translators: Comment author title. 1: Comment author name */
-				printf(ent2ncr(__('By: %s')), get_comment_author_rss());
-			}
-		?></title>
-		<link rel="alternate" href="<?php comment_link(); ?>" type="<?php bloginfo_rss('html_type'); ?>" />
+		<title>
+		<?php
+		if ( ! is_singular() ) {
+			$title = get_the_title( $comment_post->ID );
+			/** This filter is documented in wp-includes/feed.php */
+			$title = apply_filters( 'the_title_rss', $title );
+			/* translators: Individual comment title. 1: Post title, 2: Comment author name */
+			printf( ent2ncr( __( 'Comment on %1$s by %2$s' ) ), $title, get_comment_author_rss() );
+		} else {
+			/* translators: Comment author title. %s: Comment author name */
+			printf( ent2ncr( __( 'By: %s' ) ), get_comment_author_rss() );
+		}
+		?>
+			</title>
+			<link rel="alternate" href="<?php comment_link(); ?>" type="<?php bloginfo_rss( 'html_type' ); ?>" />
 
 		<author>
 			<name><?php comment_author_rss(); ?></name>
-			<?php if (get_comment_author_url()) echo '<uri>' . get_comment_author_url() . '</uri>'; ?>
+			<?php
+			if ( get_comment_author_url() ) {
+				echo '<uri>' . get_comment_author_url() . '</uri>';}
+			?>
 
 		</author>
 
 		<id><?php comment_guid(); ?></id>
-		<updated><?php echo mysql2date('Y-m-d\TH:i:s\Z', get_comment_time('Y-m-d H:i:s', true, false), false); ?></updated>
-		<published><?php echo mysql2date('Y-m-d\TH:i:s\Z', get_comment_time('Y-m-d H:i:s', true, false), false); ?></published>
-<?php if ( post_password_required($comment_post) ) : ?>
+		<updated><?php echo mysql2date( 'Y-m-d\TH:i:s\Z', get_comment_time( 'Y-m-d H:i:s', true, false ), false ); ?></updated>
+		<published><?php echo mysql2date( 'Y-m-d\TH:i:s\Z', get_comment_time( 'Y-m-d H:i:s', true, false ), false ); ?></published>
+		<?php if ( post_password_required( $comment_post ) ) : ?>
 		<content type="html" xml:base="<?php comment_link(); ?>"><![CDATA[<?php echo get_the_password_form(); ?>]]></content>
-<?php else : // post pass ?>
+	<?php else : // post pass ?>
 		<content type="html" xml:base="<?php comment_link(); ?>"><![CDATA[<?php comment_text(); ?>]]></content>
-<?php endif; // post pass
+		<?php
+	endif; // post pass
 	// Return comment threading information (https://www.ietf.org/rfc/rfc4685.txt)
-	if ( $comment->comment_parent == 0 ) : // This comment is top level ?>
-		<thr:in-reply-to ref="<?php the_guid(); ?>" href="<?php the_permalink_rss() ?>" type="<?php bloginfo_rss('html_type'); ?>" />
-<?php else : // This comment is in reply to another comment
-	$parent_comment = get_comment($comment->comment_parent);
-	// The rel attribute below and the id tag above should be GUIDs, but WP doesn't create them for comments (unlike posts). Either way, it's more important that they both use the same system
-?>
-		<thr:in-reply-to ref="<?php comment_guid($parent_comment) ?>" href="<?php echo get_comment_link($parent_comment) ?>" type="<?php bloginfo_rss('html_type'); ?>" />
-<?php endif;
+	if ( $comment->comment_parent == 0 ) : // This comment is top level
+		?>
+	<thr:in-reply-to ref="<?php the_guid(); ?>" href="<?php the_permalink_rss(); ?>" type="<?php bloginfo_rss( 'html_type' ); ?>" />
+		<?php
+	else : // This comment is in reply to another comment
+		$parent_comment = get_comment( $comment->comment_parent );
+		// The rel attribute below and the id tag above should be GUIDs, but WP doesn't create them for comments (unlike posts). Either way, it's more important that they both use the same system
+		?>
+		<thr:in-reply-to ref="<?php comment_guid( $parent_comment ); ?>" href="<?php echo get_comment_link( $parent_comment ); ?>" type="<?php bloginfo_rss( 'html_type' ); ?>" />
+		<?php
+endif;
 	/**
 	 * Fires at the end of each Atom comment feed item.
 	 *
@@ -118,7 +128,10 @@
 	 * @param int $comment_post_id ID of the post the current comment is connected to.
 	 */
 	do_action( 'comment_atom_entry', $comment->comment_ID, $comment_post->ID );
-?>
+	?>
 	</entry>
-<?php endwhile; endif; ?>
+		<?php
+	endwhile;
+endif;
+?>
 </feed>