Ticket #18632: link-template-patch.diff

wp-includes/link-template.php

@@ -2405 +2405 @@
         $shortlink = '';
 
         // Return p= link for posts.
-        if ( !empty($post_id) && '' != get_option('permalink_structure') ) {
+        if ( !empty($post_id) ) {
                 $post = get_post($post_id);
                 if ( isset($post->post_type) && 'post' == $post->post_type )
                         $shortlink = home_url('?p=' . $post->ID);