PIR-only segfault

[coke]

See  Original Ticket.

This code segfaults in trunk:

.sub main :main
  push_eh handler
    test()
  pop_eh
  ## NB: This makes sure the sub call PC is sufficiently
  ## different from the exception handler PC.
  print "foo\n"
  print "bar\n"
  .return ()
handler:
  pop_eh
  .local pmc exception
  .local string message
  .get_results (exception, message)
  print "Error: "
  print message
.end

.sub test
  ## Throw an exception.
  $P0 = new 'Exception'
  $P0 = 'oops'
  throw $P0
.end