ghc -Onot -fstrictness --make Main1.hs && ghc -Onot -fstrictness --make Main2.hs && ghc -Onot -fstrictness --make Main3.hs

time Main1 < nums
real    0m39.530s
user    0m0.015s
sys     0m0.030s

time Main2 < nums
real    0m14.078s
user    0m0.015s
sys     0m0.015s

time Main3.exe < nums
real    0m41.342s
user    0m0.015s
sys     0m0.015s

still, i'm going to google up strictness analysis to at least know what made no difference in this case ;-)

btw, why is the example #2 (http://shootout.alioth.debian.org/gp4/benchmark.php?test=sumcol&lang=ghc&id=2) (which kicks collective asses of all other participants) not considered in the shootout ? Too much optimizations ?

On Tue, Oct 7, 2008 at 6:27 AM, Don Stewart <dons@galois.com> wrote:

666wman:

> just for the kicks i tried the new version of bytestring without -O2 and
> the results were even worse:

Note that without -O or -O2 no strictness analysis is performed. So that
tail recursive loop ... won't be. You could try -Onot -fstrictness just
for kicks, to see why strictness analysis is important when writing in a
tail recursive style.

-- Don