#8553: ASSERT failed compiler/typecheck/TcMType.lhs line 809 --------------------------------------------+------------------------------ Reporter: nomeata | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler (Type checker) | Version: 7.7 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: Type of failure: Compile-time crash | Unknown/Multiple Test Case: gadt6 T7474 T5246 | Difficulty: Unknown Blocking: | Blocked By: | Related Tickets: --------------------------------------------+------------------------------ Comment (by Simon Peyton Jones <simonpj@…>): In [changeset:"985663ea47487a9e567814ba000e81d65358bf02/ghc"]: {{{ #!CommitTicketReference repository="ghc" revision="985663ea47487a9e567814ba000e81d65358bf02" Fix type-equality in the type checker (fixes Trac #8553) For horrible reasons (Note [Comparison with OpenTypeKind] in Type), the function Type.eqType currently equates OOpenKind with *. This may or may not be a good idea (it's certainly a revolting one) but it DOES NOT WORK in the type checker, which *does* need to distinguish OpenKind and *. Rather than solve the underlying problem (I have some ideas) I just introduced a new, and very short, simple, straightforward function TcType.tcEqType to do the job. }}} -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8553#comment:4> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler