[GHC] #1223: ghc-6.6: panic! (the 'impossible' happened)

[GHC]

#1223: ghc-6.6: panic! (the 'impossible' happened)
----------------------------------+-----------------------------------------
    Reporter:  jupdike at gmail.com  |       Owner:         
        Type:  bug                |      Status:  new    
    Priority:  normal             |   Milestone:         
   Component:  Compiler           |     Version:  6.6    
    Severity:  normal             |    Keywords:         
  Difficulty:  Unknown            |    Testcase:         
Architecture:  x86                |          Os:  MacOS X
----------------------------------+-----------------------------------------
ghc-6.6: panic! (the 'impossible' happened)
  (GHC version 6.6 for i386-apple-darwin):
        checkKind: adding kind constraint
    t{tv a2M5} [tv] *
    t_a1pL{tv} [tau] t_a1pL{tv} [tau] ??

 Please report this as a GHC bug:  http://www.haskell.org/ghc/reportabug

 (Note I have a tar.gz with the offending code but it's not obvious how to
 attach a file to this ticket. If I can do it then I will upload the code
 and remove this note.)

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/1223>
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