#8095: TypeFamilies painfully slow -------------------------------------+------------------------------------- Reporter: MikeIzbicki | Owner: goldfire Type: bug | Status: new Priority: high | Milestone: 8.4.1 Component: Compiler (Type | Version: 7.6.3 checker) | Resolution: | Keywords: TypeFamilies Operating System: Unknown/Multiple | Architecture: Type of failure: Compile-time | Unknown/Multiple performance bug | Test Case: Blocked By: | Blocking: Related Tickets: #5321, #11598, | Differential Rev(s): Phab:D3752 #12506 | Wiki Page: | -------------------------------------+------------------------------------- Comment (by simonpj): As Richard says this is a direction we've been wanting to move for some time. But do read comment:15 above carefully. It's ''crucial'' to keep track of the free coercion variables of a coercion, otherwise GHC may (after discarding coercions) "optimise" a correct program into one that seg- faults. We don't wan that. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/8095#comment:41 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler