diff --git a/core/includes/update.inc b/core/includes/update.inc
index 299a81c..5e56815 100644
--- a/core/includes/update.inc
+++ b/core/includes/update.inc
@@ -613,6 +613,7 @@ function update_do_one($module, $number, $dependency_map, &$context) {

       require_once DRUPAL_ROOT . '/core/includes/errors.inc';
       $variables = _drupal_decode_exception($e);
+      unset($variables['backtrace']);
       // The exception message is run through check_plain() by _drupal_decode_exception().
       $ret['#abort'] = array('success' => FALSE, 'query' => t('%type: !message in %function (line %line of %file).', $variables));
     }
diff --git a/core/modules/simpletest/lib/Drupal/simpletest/TestBase.php b/core/modules/simpletest/lib/Drupal/simpletest/TestBase.php
index 93cdbf2..7410e0a 100644
--- a/core/modules/simpletest/lib/Drupal/simpletest/TestBase.php
+++ b/core/modules/simpletest/lib/Drupal/simpletest/TestBase.php
@@ -1078,7 +1078,9 @@ protected function exceptionHandler($exception) {
       'file' => $exception->getFile(),
     ));
     // The exception message is run through check_plain() by _drupal_decode_exception().
-    $message = format_string('%type: !message in %function (line %line of %file). <pre class="backtrace">!backtrace</pre>', _drupal_decode_exception($exception) + array(
+    $decoded_exception = _drupal_decode_exception($exception);
+    unset($decoded_exception['backtrace']);
+    $message = format_string('%type: !message in %function (line %line of %file). <pre class="backtrace">!backtrace</pre>', $decoded_exception + array(
       '!backtrace' => format_backtrace($verbose_backtrace),
     ));
     $this->error($message, 'Uncaught exception', _drupal_get_last_caller($backtrace));