The GHC Haskell compiler has been updated from version 7.8.4 to 7.10.3 in Fedora 25. Haskell packages in Fedora have been rebuilt with the new compiler, and many packages updated. Users will need to update and rebuild their own Haskell projects.
The latest stable version of GHC provides many improvements and enhancements. For details, refer to the upstream release notes: