[GHC] #7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf

[GHC]

#7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf
---------------------------------+------------------------------------------
    Reporter:  bgamari           |       Owner:  simonmar        
        Type:  bug               |      Status:  infoneeded      
    Priority:  highest           |   Milestone:  7.8.1           
   Component:  Compiler          |     Version:  7.7             
    Keywords:                    |          Os:  Unknown/Multiple
Architecture:  Unknown/Multiple  |     Failure:  Runtime crash   
  Difficulty:  Unknown           |    Testcase:                  
   Blockedby:                    |    Blocking:                  
     Related:                    |  
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Comment(by simonmar):

 Great analysis, thanks.  We do indeed seem to have lost the narrowing in
 `nextIndex`, and it happens in Core, so nothing to do with the code
 generator. I'll dig a bit deeper and see if I can find out where we went
 wrong.

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/7361#comment:30>
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