#9792: map/coerce rule never seems to fire -------------------------------------+------------------------------------- Reporter: dfeuer | Owner: ekmett Type: bug | Status: new Priority: normal | Milestone: 7.10.1 Component: Core | Version: 7.9 Libraries | Keywords: Resolution: | Architecture: Unknown/Multiple Operating System: | Difficulty: Unknown Unknown/Multiple | Blocked By: Type of failure: Runtime | Related Tickets: performance bug | Test Case: | Blocking: | Differential Revisions: | -------------------------------------+------------------------------------- Comment (by simonpj): Tracking stack depths: this will go away when Richard completes his work of treating Coercible constraints more like nominal-equality constraints. However, a value of type `Coercible a b` can certainly be bottom in Core, even if type inference engine will never produce it. More promising is just to make functions strict in `Coercible` arguments. I should look again at `-fdicts-strict`. Meanwhile Richard is also thinking about the whole lifted/unlifted equality thing, and I'd like to see how the dust settles there. Simon -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/9792#comment:11 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler