What is New in Cross Compiling Haskell

February Edition

While I didn’t manage to find the time to write anything here in February, I did make some progress on the cross compilation front.

cabal can now be invoked outside of the source folder, and tries to not pollute the source tree with generated files anymore (haskell/cabal#4874). The --with-PROG flag is now properly respected when using new-build; this allows new-build to work with cross compilers (haskell/cabal#5018). I’ve also spent quite some time to get cabals CI back into shape, which was hitting a rather obscure bug (haskell/cabal#5132).

I’ve also started working for IOHK where I will be assisting the DevOps team to Cross Compile Haskell with GHC from Linux to Windows. I’m very excited about the work we do at IOHK, and this will definitely broaden and improve GHCs cross compilation capabilities.

This does not mean I’ll stop working on the mobile cross compilers; I will still keep improving them — as I have been — and I think we are already on a very good road to get this all sorted in GHC 8.6. While my initial target was GHC 8.4, we just couldn’t get it all into GHC 8.4 in time.

If everything works out as I hope, GHC 8.6 can be built by default with the shake based build system: hadrian, and will have extensive cross compilation capabilities to various platforms.

I’d like to close with some progress we are making at IOHK with respect to cross compiling Haskell to Windows.