#14610: newtype wrapping of a monadic stack kills performance -------------------------------------+------------------------------------- Reporter: mrkkrp | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: 8.6.1 Component: Compiler | Version: 8.2.2 Resolution: | Keywords: JoinPoints Operating System: Unknown/Multiple | Architecture: Type of failure: Runtime | Unknown/Multiple performance bug | Test Case: Blocked By: | Blocking: Related Tickets: #14620 | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by nomeata):
Operationally the transformation makes sense, but it's not well typed. I have no idea how to fix this.
So am I right to say “we forbid polymorphic return types because we cannot prove it to be sound, even though we know it would not actually crash if we did allow it”? -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/14610#comment:16 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler