Ill-kinded instance head involving -XTypeInType can invoke GHC panic

This code:

{-# LANGUAGE FlexibleInstances, TypeInType #-}
module FvProvFallsIntoAHole where

import Data.Kind

newtype UhOh (k :: * -> *) (a :: k *) = UhOh (k *)
instance Functor k => Functor (UhOh k) where

produces this GHC panic:

$ /opt/ghc/head/bin/ghc FvProvFallsIntoAHole.hs
[1 of 1] Compiling FvProvFallsIntoAHole ( FvProvFallsIntoAHole.hs, FvProvFallsIntoAHole.o )
ghc: panic! (the 'impossible' happened)
  (GHC version 8.1.20160108 for x86_64-unknown-linux):
        fvProv falls into a hole {aq6}

Please report this as a GHC bug:  http://www.haskell.org/ghc/reportabug

Trac metadata

Trac field	Value
Version	8.1
Type	Bug
TypeOfFailure	OtherFailure
Priority	normal
Resolution	Unresolved
Component	Compiler (Type checker)
Test case
Differential revisions
BlockedBy
Related
Blocking
CC	goldfire
Operating system
Architecture