[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:  dfeuer
            Type:  bug               |               Status:  new
        Priority:  high              |            Milestone:  8.2.1
       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):

 >  Are we hoping to be able to reintroduce the inlines and merge the
 classes?

 Well, the original Description says that compiling Cabal with GHC 8.0 was
 26x slower than compiling with GHC 7.8.  That's a big difference.  How
 long does it take to compile (the same) Cabal with GHC 8.2?  That's the
 question at hand.  If it's still 26x slower (and your comment suggests
 that it is, albeit maybe not 26x), I'd love to dig a bit into why.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9630#comment:52>
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