diff --git a/wp-includes/user.php b/wp-includes/user.php
index 028606385b..6f5dae67f9 100644
--- a/wp-includes/user.php
+++ b/wp-includes/user.php
@@ -420,7 +420,7 @@ function count_many_users_posts( $users, $post_type = 'post', $public_only = fal
  *
  * @since MU
  *
- * @return int The current user's ID
+ * @return int The current user's ID, or 0 if no user is logged in.
  */
 function get_current_user_id() {
 	if ( ! function_exists( 'wp_get_current_user' ) )
diff --git a/wp-includes/version.php b/wp-includes/version.php
index b86422280a..59c1779836 100644
--- a/wp-includes/version.php
+++ b/wp-includes/version.php
@@ -4,7 +4,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '4.8-alpha-39483';
+$wp_version = '4.8-alpha-39486';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.