[GHC] #1033: ghc-6.7: panic! (the 'impossible' happened) -- typechecker getting confused by Data.Generics?

[GHC]

#1033: ghc-6.7: panic! (the 'impossible' happened) -- typechecker getting confused
by Data.Generics?
-------------------------------------+---------------------------------
        Reporter:  int-e             |         Owner:
            Type:  bug               |        Status:  closed
        Priority:  normal            |     Milestone:
       Component:  Compiler          |       Version:  6.7
      Resolution:  fixed             |      Keywords:
Operating System:  Unknown/Multiple  |  Architecture:  Unknown/Multiple
      Difficulty:  Unknown           |     Test Case:  tc220
-------------------------------------+---------------------------------

Comment (by simonpj <simonpj@…>):

 In [changeset:"fbdb1520c3bb5048cbe257cd14a96a6dc8e1da2e/ghc"]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="fbdb1520c3bb5048cbe257cd14a96a6dc8e1da2e"
 Add test for Trac #1033
 }}}

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/1033#comment:4>
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