panic on type family
Ghc panics on this module:
{-# LANGUAGE TypeFamilies #-}
type family Element c :: *
f :: Element x
f = undefined
------
ghc-6.8.0.20070921: panic! (the 'impossible' happened)
(GHC version 6.8.0.20070921 for i386-unknown-linux):
check_tau_type main:Main.Element{tc r5C} x{tv a5F} [tv]
Please report this as a GHC bug: http://www.haskell.org/ghc/reportabug