if STDIN is detected closed, subprocesses spawned by portupgrade show no ouput.
STDIN is detected closed if portupgrade is a run inside a KDE or Qt Process.
this makes it impossible to monitor output correctly.

Fix: 

fix the logged_command function (~ lines 480-490) in pkgtools.rb to read


def logged_command(file, args)
  if !file  
    args
  else 
    ['/usr/bin/script', '-qa', file, *args]
  end
end


instead of


def logged_command(file, args)
  if !file  
    args
  elsif STDIN.tty?
    ['/usr/bin/script', '-qa', file, *args]
  else
    ['/bin/sh', '-c', sprintf('%s >>%s 2>&1', shelljoin(*args), shelljoin(file))]
  end
end

basically just remove the STDIN condition for the second call and remove the third.
How-To-Repeat: add <&- on the commandline, e.g.:
portupgrade -v -y -N -PP games/angband <&-