From 8861a546b8ca766fff447081e90c9a67a4a822f4 Mon Sep 17 00:00:00 2001
From: xjm <xjm@65776.no-reply.drupal.org>
Date: Sat, 20 Oct 2018 02:14:35 -0500
Subject: [PATCH] Issue #2575105 by alexpott: hotfix for PHP 5 test failures in
 ShutdownFunctionsTest

---
 core/includes/bootstrap.inc | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/core/includes/bootstrap.inc b/core/includes/bootstrap.inc
index 45c9490713b..ebcd2176a73 100644
--- a/core/includes/bootstrap.inc
+++ b/core/includes/bootstrap.inc
@@ -1033,8 +1033,12 @@ function _drupal_shutdown_function() {
   chdir(DRUPAL_ROOT);
 
   try {
-    foreach ($callbacks as &$callback) {
+    reset($callbacks);
+    // Do not use foreach() here because it is possible that the callback will
+    // add to the $callbacks array via drupal_register_shutdown_function().
+    while ($callback = current($callbacks)) {
       call_user_func_array($callback['callback'], $callback['arguments']);
+      next($callbacks);
     }
   }
   // PHP 7 introduces Throwable, which covers both Error and