Kind variable problem when declaring associated type family

The following code fails to compile:

{-# LANGUAGE PolyKinds, TypeFamilies #-}

class Foo a where
  type Bar a
  type Bar a = Int

The error I get is

    Type indexes must match class instance head
    Found `k' but expected `k'
    In the type synonym instance default declaration for `Bar'
    In the class declaration for `Foo'

When I remove -XPolyKinds, the code compiles without a hiccup.

This was tested on 7.5.2012.0710

Trac metadata

Trac field	Value
Version	7.5
Type	Bug
TypeOfFailure	OtherFailure
Priority	normal
Resolution	Unresolved
Component	Compiler (Type checker)
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