[GHC] #11725: Performance Regression from 7.8.3 to 7.10.3

[GHC]

#11725: Performance Regression from 7.8.3 to 7.10.3
-------------------------------------+-------------------------------------
        Reporter:  dominic           |                Owner:
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  7.10.3
      Resolution:                    |             Keywords:
Operating System:  Linux             |         Architecture:
 Type of failure:  Runtime           |  Unknown/Multiple
  performance bug                    |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by dominic):

 It's entirely possible that this has been solved in 8.0.1 so I have built
 this compiler on OS X 10.11.3. At the moment I can't build one of the
 packages on which my example depends

 {{{
 ~/Dropbox/Private/Random8 $ ~/Library/Haskell/ghc-7.10.3/lib/cabal-
 install-1.25.0.0/bin/cabal install flexible-defaults --constraint
 ="template-haskell==2.11.0.0" --with-ghc=/Users/dom/ghc/inplace/bin/ghc-
 stage2
 ~/Library/Haskell/ghc-7.10.3/lib/cabal-install-1.25.0.0/bin/cabal install
 flexible-defaults --constraint="template-haskell==2.11.0.0" --with-
 ghc=/Users/dom/ghc/inplace/bin/ghc-stage2
 Resolving dependencies...
 cabal: Entering directory
 '/var/folders/3p/m593dprn5snbjz6sc45c77f80000gn/T/cabal-tmp-99610
 /flexible-defaults-0.0.0.2'
 Configuring flexible-defaults-0.0.0.2...
 Building flexible-defaults-0.0.0.2...
 Preprocessing library flexible-defaults-0.0.0.2...
 [1 of 3] Compiling Language.Haskell.TH.FlexibleDefaults.Solve (
 src/Language/Haskell/TH/FlexibleDefaults/Solve.hs, dist/dist-sandbox-
 59d6d2c7/build/Language/Haskell/TH/FlexibleDefaults/Solve.o )

 src/Language/Haskell/TH/FlexibleDefaults/Solve.hs:13:1: warning:
     The import of ‘Data.Monoid’ is redundant
       except perhaps to import instances from ‘Data.Monoid’
     To import instances alone, use: import Data.Monoid()
 [2 of 3] Compiling Language.Haskell.TH.FlexibleDefaults.DSL (
 src/Language/Haskell/TH/FlexibleDefaults/DSL.hs, dist/dist-sandbox-
 59d6d2c7/build/Language/Haskell/TH/FlexibleDefaults/DSL.o )

 src/Language/Haskell/TH/FlexibleDefaults/DSL.hs:79:82: error:
     Not in scope: type constructor or class ‘InlineSpec’

 src/Language/Haskell/TH/FlexibleDefaults/DSL.hs:90:32: error:
     Not in scope: type constructor or class ‘InlineSpec’

 src/Language/Haskell/TH/FlexibleDefaults/DSL.hs:121:14: error:
     Not in scope: type constructor or class ‘InlineSpec’
 cabal: Leaving directory '/var/folders/3p/m593dprn5snbjz6sc45c77f80000gn/T
 /cabal-tmp-99610/flexible-defaults-0.0.0.2'
 Failed to install flexible-defaults-0.0.0.2
 cabal: Error: some packages failed to install:
 flexible-defaults-0.0.0.2 failed during the building phase. The exception
 was:
 ExitFailure 1
 }}}

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11725#comment:1>
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