[GHC] #7436: Derived Foldable and Traversable instances become extremely inefficient due to eta-expansion

[GHC]

#7436: Derived Foldable and Traversable instances become extremely inefficient due
to eta-expansion
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    Reporter:  shachaf           |       Owner:                         
        Type:  bug               |      Status:  patch                  
    Priority:  normal            |   Milestone:                         
   Component:  Compiler          |     Version:  7.6.1                  
    Keywords:                    |          Os:  Unknown/Multiple       
Architecture:  Unknown/Multiple  |     Failure:  Runtime performance bug
  Difficulty:  Unknown           |    Testcase:                         
   Blockedby:                    |    Blocking:                         
     Related:                    |  
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Comment(by twanvl):

 I added an explanation of the behaviour and a link to this ticket to the
 description at the top of the Functor deriving code. I did not make it a
 separate note, since there is no reference to it from inside the code. The
 patch that adds this note is attached.

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/7436#comment:14>
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