Index: src/wp-settings.php
===================================================================
--- src/wp-settings.php	(revision 38274)
+++ src/wp-settings.php	(working copy)
@@ -20,7 +20,7 @@
 // Include files required for initialization.
 require( ABSPATH . WPINC . '/load.php' );
 require( ABSPATH . WPINC . '/default-constants.php' );
-require( ABSPATH . WPINC . '/plugin.php' );
+require_once( ABSPATH . WPINC . '/plugin.php' );
 
 /*
  * These can't be directly globalized in version.php. When updating,