GHC options in Cabal

Duncan Coutts duncan.coutts at
Thu Jan 17 17:39:49 EST 2008

On Thu, 2008-01-17 at 13:51 +0000, Adrian Hey wrote:
> Hello,
> Looking at the latest Cabal docs, I see that in addition to ghc-options,
> there are also ghc-prof-options and ghc-shared-options. What isn't clear
> to me though from the docs is that are the latter two in addition to the
> first, or are they a substitute for the first (for profiling/shared).
> IOW, if I already have..
> ghc-options: -O2
> will the O2 also be applied to profiling build (say)? Or do I need an
> extra explicit..
> ghc-prof-options: -O2

They are additive.

I'm not at all convinced about these fields. It's not clear what their
use cases are.

As Adam says, adding -O is discouraged. If I had my way I'd make hackage
require a performance profile to be supplied along with any package that
wanted to use -O2 over -O.


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