Issue #3138522: WARNING | Since PHP 7.0, functions inspecting arguments, like debug_backtrace()

htmlmail.mail.inc

@@ -233,7 +233,6 @@ class HTMLMailSystem implements MailSystemInterface {
    *   - MailMIME: The message, parsed into a MailMIME object.
    */
   public function mail(array $raw_message) {
-    $trace = debug_backtrace(0);
     $eol = variable_get('mail_line_endings', MAIL_LINE_ENDINGS);
     // Ensure that subject is non-null.
     $message = $raw_message + array('subject' => t('(No subject)'));
@@ -316,15 +315,7 @@ class HTMLMailSystem implements MailSystemInterface {
       foreach ($params as $i => $value) {
         $params[$i] = var_export($value, 1);
       }
-      if (defined('DEBUG_BACKTRACE_IGNORE_ARGS')) {
-        $trace = print_r(debug_backtrace(DEBUG_BACKTRACE_IGNORE_ARGS), 1);
-      }
-      else {
-        for ($i = count($trace) - 1; $i >= 0; $i--) {
-          unset($trace[$i]['args']);
-        }
-        $trace = print_r($trace);
-      }
+      $trace = print_r(debug_backtrace(DEBUG_BACKTRACE_IGNORE_ARGS), 1);
       watchdog('htmlmail', 'Mail sending failed because:<br /><pre>@call</pre><br />returned FALSE.<br /><pre>@trace</pre>', array('@call' => $call, '@trace' => $trace));
     }
     return $result;