ghc panic with TypeError

When playing around with TypeError I got a ghc panic with the following code:

{-# LANGUAGE DataKinds, FlexibleContexts, TypeOperators,
     FlexibleInstances, UndecidableInstances #-}

import GHC.TypeLits

class C t where

instance
    (TypeError (Text "A" :<>: {- Text -} "B"))
    => C t where

main :: IO ()
main = return ()

Compiling this results in

ghc: panic! (the 'impossible' happened)
  (GHC version 8.0.0.20160204 for x86_64-unknown-linux):
	fvProv falls into a hole {a1bh}

Commenting "in" the second Text removes the panic.

Trac metadata

Trac field	Value
Version	7.10.3
Type	Bug
TypeOfFailure	OtherFailure
Priority	normal
Resolution	Unresolved
Component	Compiler
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