[GHC] #9630: compile-time performance regression (probably due to Generics)

[GHC]

#9630: compile-time performance regression (probably due to Generics)
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        Reporter:  hvr               |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  high              |            Milestone:  8.4.1
       Component:  Compiler          |              Version:  7.9
      Resolution:                    |             Keywords:  deriving-
                                     |  perf, Generics
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Compile-time      |  Unknown/Multiple
  performance bug                    |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:  #9583, #10293,    |  Differential Rev(s):
  #13059, #10818                     |
       Wiki Page:                    |
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Comment (by simonpj):

 > 1024 specialization rules to -ddump-rules for this module.

 Really?  I compiled the module in comment:22 with HEAD and got no rules at
 all!  What am I doing wrong?

 {{{
 Result size of Tidy Core
   = {terms: 2,582, types: 63,214, coercions: 20,656, joins: 0/34}
 }}}
 Simon

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9630#comment:42>
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