[GHC] #5970: Type checker hangs

[GHC]

#5970: Type checker hangs
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    Reporter:  Lemming                  |       Owner:                              
        Type:  bug                      |      Status:  infoneeded                  
    Priority:  normal                   |   Milestone:                              
   Component:  Compiler (Type checker)  |     Version:  7.4.1                       
    Keywords:                           |          Os:  Linux                       
Architecture:  x86                      |     Failure:  Compile-time performance bug
  Difficulty:  Unknown                  |    Testcase:                              
   Blockedby:                           |    Blocking:                              
     Related:                           |  
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Comment(by Lemming):

 When trying to reduce the module to a small testcase I hit bug #5978. I
 had a small hope that the type checking time issue would go away magically
 when fixing #5978. Even if #5970 and #5978 are not related, hunting a
 compiler bug in the presence of another one is a bit more complicated. The
 testcase for this ticket is especially hard to simplify, since
 simplification means reduction of type checking time and I can hardly
 judge what type checking time is reasonable and what is too slow.

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/5970#comment:7>
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