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Out-of-memory crash when using RULES and type families

GHC(i) 7.4.1 crashes with an OOM error on the following code:

{-# LANGUAGE NoImplicitPrelude, TypeFamilies #-}

import Prelude (undefined,Bool(..),Show(..),(.))

type family Elem f :: *
type family Subst f b :: *

class (Subst fa (Elem fa) ~ fa) => F fa where
	(<$>) :: (Elem fa ~ a, Elem fb ~ b,
	          Subst fa b ~ fb, Subst fb a ~ fa) =>
			 (a -> b) -> (fa -> fb)

{-# RULES
"map/map" forall f g xs. f <$> (g <$> xs) = (f.g) <$> xs
	#-}
Trac metadata
Trac field Value
Version 7.4.1
Type Bug
TypeOfFailure OtherFailure
Priority normal
Resolution Unresolved
Component Compiler
Test case
Differential revisions
BlockedBy
Related
Blocking
CC
Operating system
Architecture
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