From 28c3f6e4d8bc016762f7f69eafe246315d57834b Mon Sep 17 00:00:00 2001
From: Jake Dallimore <jake@moodle.com>
Date: Wed, 30 May 2018 09:55:23 +0800
Subject: [PATCH] MDL-60819 core_files: fix exception thrown from
 generate_image_thumbnail

This function now requires gdlib.php.
---
 lib/filestorage/stored_file.php | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/lib/filestorage/stored_file.php b/lib/filestorage/stored_file.php
index 0f67664bdfb..f1c3f759f03 100644
--- a/lib/filestorage/stored_file.php
+++ b/lib/filestorage/stored_file.php
@@ -1063,6 +1063,9 @@ class stored_file {
      * @return  string|bool false if a problem occurs, the thumbnail image data otherwise
      */
     public function generate_image_thumbnail($width, $height) {
+        global $CFG;
+        require_once($CFG->libdir . '/gdlib.php');
+
         if (empty($width) or empty($height)) {
             return false;
         }