How to set ghc-options for whole package set?

[phile314]

For our production deployment, we would like to compile all packages with -O2. As far as I can see, the ghcOptions ( https://input-output-hk.github.io/haskell.nix/reference/modules/#packagespackageghcoptions ) can only be set per-package. Is there an easy way to compile a complete package set with -O2?

[michaelpj]

Am I right that you only want to do this sometimes, i.e. it wouldn't be sufficient to add:

package *
    optimization: 2

to your cabal.project? I think that would have the effect of setting it up, but I get the impression you want to do this on the Nix side?

Independently, I agree that it would be nice to be able to set ghcOptions as a top-level option.

[phile314]

Thanks for the quick reply!

Yes, I would prefer to do this on the nix side. For development we use stack build and as build times are already slow, we don't want -O2 there. For production on the other hand we don't care if builds take a few minutes longer and want to enable this for everything. By everything I also mean packages from stackage etc., e.g. aeson. Not sure if it should also apply to the libraries bundled with GHC.

For context, we are using callStackToNix to compute the nix build from our stack files.

[michaelpj]

Fixed by #1046