(strange) huge difference

I was surprised when the very simple following program, once compiled with GHC-4.08.1, generated a 28.8 Kb file, but when compiled with GHC-5.02 generated a 436 Kb file. Is this the GHC behavior to be expected? fac :: Int -> Int fac n = product [1..n] main :: IO () main = do putStrLn "HELLO WORLD" putStrLn (show (fac 5)) -- Andre