[GHC] #7729: GHC panics. Invalid core

[GHC]

#7729: GHC panics. Invalid core
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  Reporter:  Khudyakov                               |          Owner:                  
      Type:  bug                                     |         Status:  new             
  Priority:  normal                                  |      Milestone:  7.6.3           
 Component:  Compiler                                |        Version:  7.6.2           
Resolution:                                          |       Keywords:                  
        Os:  Unknown/Multiple                        |   Architecture:  Unknown/Multiple
   Failure:  None/Unknown                            |     Difficulty:  Unknown         
  Testcase:  indexed_types/should_fail/T7729,T7729a  |      Blockedby:                  
  Blocking:                                          |        Related:                  
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Comment(by monoidal):

 For the record, I confirm that ekmett's program and the original ticket
 concerns exactly the same bug, fixed in HEAD. Both programs can be reduced
 to http://hpaste.org/88612, which crashes 7.6 and gives occurs check in
 7.7. I don't think this bug is worth hunting and releasing another 7.6.x -
 I would close it.

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/7729#comment:5>
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