[GHC] #3843: Merge plugins into HEAD

[GHC]

#3843: Merge plugins into HEAD
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    Reporter:  dreixel           |        Owner:  simonpj     
        Type:  task              |       Status:  new         
    Priority:  normal            |    Milestone:  7.0.2       
   Component:  Compiler          |      Version:  6.13        
    Keywords:                    |     Testcase:              
   Blockedby:                    |   Difficulty:              
          Os:  Unknown/Multiple  |     Blocking:              
Architecture:  Unknown/Multiple  |      Failure:  None/Unknown
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Comment(by batterseapower):

 ESC and supercompilation could be implemented by plugin passes. I think I
 even added an API to report warnings from Core plugins with ESC in mind.
 Not sure if that made it into the patch above.

 If you want linking to work well you need to break annotations out into a
 separate package. As it stands, because of how GHC handles module
 initialisation, the linker is unable to remove TONS of dead Haskell code.
 So for example if you use QuasiQuoting then your executables bloat because
 we link in most of GHC even though you only needed it it at compiled time!
 There is an open ticket about this (search for "Quasiquoting without
 bloating")

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/3843#comment:19>
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