[GHC] #9701: GADTs not specialized properly

[GHC]

#9701: GADTs not specialized properly
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              Reporter:  dfeuer      |            Owner:
                  Type:  bug         |           Status:  new
              Priority:  normal      |        Milestone:
             Component:  Compiler    |          Version:  7.9
            Resolution:              |         Keywords:
      Operating System:              |     Architecture:  Unknown/Multiple
  Unknown/Multiple                   |       Difficulty:  Unknown
       Type of failure:  Runtime     |       Blocked By:
  performance bug                    |  Related Tickets:
             Test Case:              |
              Blocking:              |
Differential Revisions:              |
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Comment (by dfeuer):

 I just realized that you might not find that example as convincing as this
 one:

 {{{#!hs
 data Silly a where Silly :: Num a => a -> Silly a

 double :: Int -> Int
 double n = n + n

 oops :: Silly Int -> Int
 oops (Silly x) = double x
 }}}

 Now if `double` gets inlined, it will use the `Num` dictionary from
 `Silly`, but if it's not inlined, it will use the usual one.

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9701#comment:10>
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