Gtk2Hs Cairo + Pango Hello World

gistfile1.hs

-- Reqs: apt-get install libghc6-time-dev libghc6-cairo-dev libghc6-gtk-dev
-- Compile by doing
-- ghc --make hello.hs -o hello

import Graphics.UI.Gtk hiding (fill)
import Graphics.Rendering.Cairo
import Data.Time.Clock.POSIX
import Time

frac = snd . properFraction

modf a b = frac (a / b) * b

normalizeAngle a | a < 0 = 2*pi + (a `modf` (2*pi))
normalizeAngle a         = a `modf` (2*pi)

floorf = fromInteger . fst . properFraction

quantize d f = d * floorf (f / d)

angularDistance a b =
  f (na - nb)
  where na = normalizeAngle a
        nb = normalizeAngle b
        f a | a > pi  = a - 2*pi
        f a | a < -pi = a + 2*pi
        f a           = a

exposeHandler widget e = do
  drawWin <- widgetGetDrawWindow widget
  (wi,hi) <- widgetGetSize widget
  let (w,h) = (realToFrac wi, realToFrac hi)
  t <- getPOSIXTime
  let n = 20
  let rot = normalizeAngle (realToFrac t)
  renderWithDrawable drawWin $ do
    save
    translate (w * 0.55) (h * 0.40)
    arc 0 0 (w * 0.2) 0 (pi*2)
    setLineWidth 20
    stroke
    renderWithSimilarSurface ContentAlpha 200 40 $ \tmp -> do
      renderWith tmp $ do
        scale 1.5 1.5
        createLayout "God damn it" >>= showLayout
      withPatternForSurface tmp $ \pat -> do
        mapM_ (\i -> do
          let trot = normalizeAngle $ rot + (i * (pi * 2) / n)
          let sc = (1.0 + 0.5*(sin trot)) / 1.5
          let tl = ((w*0.2+10) / sqrt 2)
          save
          rotate trot
          translate tl tl
          scale sc sc
          translate 10 10
          setSource pat
          rectangle 0 0 200 40
          fill
          restore ) [1..n]
    restore
  widgetQueueDraw widget
  return True

main = do
  initGUI
  window <- windowNew
  da <- drawingAreaNew
  set window [ containerChild := da ]
  windowSetDefaultSize window 410 450
  onExpose da (exposeHandler da)
  onDestroy window mainQuit
  widgetShowAll window
  mainGUI

what ghc does this run with?