Strict foldl

Hi Haskellers, which compiler settings do I have to pass to ghc-5.02 in order to achieve that the strictness analyzer recognizes strictness of (+) in foldl and computes sum in constant space? Prelude> sum [1..10000000] had the following effect: PID USER PRI NI SIZE RSS SHARE STAT %CPU %MEM TIME COMMAND 23542 herrmann 20 0 250M 130M 97500 R 66.3 52.4 0:21 ghc-5.02 Of course, one could define a strict foldl oneself:

sfoldl f e [] = e sfoldl f e (x:xs) = (sfoldl f $! (f e x)) xs

( > sfoldl (+) 0 [1..10000000] returns 50000005000000 in about a minute interpreted using 18MB of total space.) But with the own definition one has to redefine many of the prelude functions. Thanks in advance -- Christoph Herrmann