• Add : If a non-len magic callback returns a reference, it will now
  only be freed at the end of the statement that caused the
  magic to trigger. This allows the user to attach free magic
  (or a plain destructor) to a token returned from the callbacks
  in order to defer an action after the magic is processed by
  perl.
  
• Fix : Test failures of threads tests on systems with harsh resource
  constraints causing the threads to exit() during run.