-O in 6.8.1-candidate

[Don Stewart]

mechvel:
> Dear GHC developers, 
> 
> Has  -O  any meaning in  ghc-6.8.1-candidate ?
> 
> I build  docon  under  ghc-6.8.1-candidate  under -O and 
> with skipping it (the line of  -O  commented out in  docon.cabal). 
> 
> And it installs the .a library of the same size, 
> and the test running takes the same time.
> 

By default cabal uses ghc -O to build projects, so you won't see any
difference if you comment it out of the cabal file. You will however
if you explicitly turn off optimisations:

    ghc-options: -Onot

I'd recommend using -O2 these days, particularly for a library like
docon where performance matters. 

    ghc-options: -O2

For best results.

-- Don