diff --git a/src/wp-includes/post.php b/src/wp-includes/post.php
index f4a20909d2..72ef1641aa 100644
--- a/src/wp-includes/post.php
+++ b/src/wp-includes/post.php
@@ -4858,6 +4858,8 @@ function wp_update_attachment_metadata( $post_id, $data ) {
  *
  * @since 2.1.0
  *
+ * @global string $pagenow
+ *
  * @param int $post_id Optional. Attachment ID. Default 0.
  * @return string|false Attachment URL, otherwise false.
  */