Ticket #15565: 15565.1.diff

wp-includes/comment.php

@@ -1562 +1562 @@
 
         $old = (int) $post->comment_count;
         $new = (int) $wpdb->get_var( $wpdb->prepare("SELECT COUNT(*) FROM $wpdb->comments WHERE comment_post_ID = %d AND comment_approved = '1'", $post_id) );
+
+        do_action('wp_updating_comment_count', $post_id, $new, $old);
+
         $wpdb->update( $wpdb->posts, array('comment_count' => $new), array('ID' => $post_id) );
 
         if ( 'page' == $post->post_type )