Re: [GHC] #8773: Require -XIncoherentInstances to write role annotations on class definitions

#8773: Require -XIncoherentInstances to write role annotations on class definitions -------------------------------------+------------------------------------ Reporter: goldfire | Owner: goldfire Type: bug | Status: new Priority: normal | Milestone: 7.8.1 Component: Compiler | Version: 7.8.1-rc1 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: Unknown/Multiple Type of failure: None/Unknown | Difficulty: Unknown Test Case: | Blocked By: Blocking: 8745 | Related Tickets: #8745 -------------------------------------+------------------------------------ Comment (by Richard Eisenberg ): In [changeset:"138297585f88351352e0ed878b25f26e1d6edfef/ghc"]: {{{ #!CommitTicketReference repository="ghc" revision="138297585f88351352e0ed878b25f26e1d6edfef" Fix #8773. To make a role annotation on a class asserting a role other than nominal, you now need -XIncoherentInstances. See the ticket for more information as to why this is a good idea. }}} -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/8773#comment:4 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler