Ticket #22258: 22258.2.diff

wp-includes/functions.php

@@ -902 +902 @@
 function wp_get_nocache_headers() {
         $headers = array(
                 'Expires' => 'Wed, 11 Jan 1984 05:00:00 GMT',
-                'Last-Modified' => gmdate( 'D, d M Y H:i:s' ) . ' GMT',
+                'Last-Modified' => '',
                 'Cache-Control' => 'no-cache, must-revalidate, max-age=0',
                 'Pragma' => 'no-cache',
         );
@@ -926 +926 @@
         $headers = wp_get_nocache_headers();
         foreach( $headers as $name => $field_value )
                 @header("{$name}: {$field_value}");
+        if ( function_exists('header_remove') )
+                header_remove( 'Last-Modified' );
 }
 
 /**

wp-includes/class-wp.php

@@ -320 +320 @@
                 $headers = array('X-Pingback' => get_bloginfo('pingback_url'));
                 $status = null;
                 $exit_required = false;
+                $nocache_headers = false;
 
-                if ( is_user_logged_in() )
+                if ( is_user_logged_in() ) {
                         $headers = array_merge($headers, wp_get_nocache_headers());
+                        $nocache_headers = true;
+                }
+
                 if ( ! empty( $this->query_vars['error'] ) ) {
                         $status = (int) $this->query_vars['error'];
                         if ( 404 === $status ) {
-                                if ( ! is_user_logged_in() )
+                                if ( ! is_user_logged_in() ) {
                                         $headers = array_merge($headers, wp_get_nocache_headers());
+                                        $nocache_headers = true;
+                                }
                                 $headers['Content-Type'] = get_option('html_type') . '; charset=' . get_option('blog_charset');
                         } elseif ( in_array( $status, array( 403, 500, 502, 503 ) ) ) {
                                 $exit_required = true;
@@ -381 +387 @@
                 foreach( (array) $headers as $name => $field_value )
                         @header("{$name}: {$field_value}");
 
+                if ( $nocache_headers && function_exists('header_remove') )
+                        header_remove('Last-Modified');
+
                 if ( $exit_required )
                         exit();