[GHC] #2355: Building NDP fails with GHC panic on x86_64

[GHC]

#2355: Building NDP fails with GHC panic on x86_64
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 Reporter:  Nolari         |          Owner:                
     Type:  bug            |         Status:  new           
 Priority:  normal         |      Milestone:                
Component:  Compiler       |        Version:  6.9           
 Severity:  major          |     Resolution:                
 Keywords:  ndp ghc panic  |     Difficulty:  Unknown       
 Testcase:                 |   Architecture:  x86_64 (amd64)
       Os:  Linux          |  
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Comment (by simonpj):

 Sorry about that.  It turned out to be a subtle simplifier scoping bug,
 triggered by the desugarer changes, which meant it took a while to find.

 I have a patch, but I have not had time to validate it, and I'm about to
 go away.  For now, just use -fno-ds-multi-tyvar

 Simon

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/2355#comment:4>
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