nonsensical kind variable ascription causes panic
{-# LANGUAGE TypeFamilies, PolyKinds, MultiParamTypeClasses #-}
module GHCBug where
type family TF (t :: k) :: * -> * -> *
class C (t :: k) (dcs :: * -> * -> *)
f :: (C (t :: k) (TF t)) => TF t p1 p0 -> t p1 p0
f = undefined -- panic caused by (t :: k) in the signature's context
gives
[1 of 1] Compiling GHCBug ( GHCPanic.hs, interpreted )
ghc: panic! (the 'impossible' happened)
(GHC version 7.6.1 for x86_64-apple-darwin):
metaTvRef
<<details unavailable>>
Trac metadata
Trac field | Value |
---|---|
Version | 7.6.1 |
Type | Bug |
TypeOfFailure | OtherFailure |
Priority | normal |
Resolution | Unresolved |
Component | Compiler (Type checker) |
Test case | |
Differential revisions | |
BlockedBy | |
Related | |
Blocking | |
CC | |
Operating system | |
Architecture |