#10195: GHC forgets constraints when matching on GADTs -------------------------------------+------------------------------------- Reporter: crockeea | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 7.8.4 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: Type of failure: GHC rejects | Unknown/Multiple valid program | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Revisions: -------------------------------------+------------------------------------- Comment (by crockeea): Can you confirm in 7.10? Since we have no idea what's causing the issue, nor exactly what "this situation" is, it's possible this behavior could occur for a less generic instance in a situation where the instance constraint can't just be trivially promoted to a superclass constraint. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/10195#comment:2 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler