#8745: GeneralizedNewtypeDeriving is still not Safe -------------------------------------+------------------------------------ Reporter: goldfire | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 7.8.1-rc1 Resolution: | Keywords: Safe Operating System: Unknown/Multiple | Architecture: Unknown/Multiple Type of failure: None/Unknown | Difficulty: Unknown Test Case: | Blocked By: Blocking: | Related Tickets: -------------------------------------+------------------------------------ Changes (by thoughtpolice): * cc: nomeata (added) Comment: The GND change seems reasonable to me, and I believe we discussed it prior to this (but I can't find the mailing list post just yet) - we just need to remove `-XGeneralizedNewtypeDeriving` from `unsafeFlags` in `DynFlags`. I'm not so sure about Coerce though, at least not yet - we're still considering it somewhat experimental I think, so perhaps exposing it to Safe Haskell isn't the best idea just yet. Joachim, what are your thoughts on this? Do you think we should consider `Coercible` as safe? If so, I'm willing to defer to you here (and I'll even write the patch - but not sure where to export it from - perhaps a `Trustworthy` module called `GHC.Coerce`?) -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/8745#comment:1 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler