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GeneralizedNewtypeDeriving + MultiParamTypeClasses sends typechecker into an infinite loop

This worked in GHC 7.6.3, but ever since GHC 7.8, this code will cause the typechecker to loop infinitely:

{-# LANGUAGE FunctionalDependencies #-}
{-# LANGUAGE GeneralizedNewtypeDeriving #-}
{-# LANGUAGE MultiParamTypeClasses #-}
module Bug where

class C a b | a -> b where
  c :: a -> Int

newtype Foo a = Foo a
  deriving (C b)
Trac metadata
Trac field Value
Version 8.0.1
Type Bug
TypeOfFailure OtherFailure
Priority normal
Resolution Unresolved
Component Compiler (Type checker)
Test case
Differential revisions
BlockedBy
Related
Blocking
CC
Operating system
Architecture
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