[GHC] #12822: Cleanup GHC verbosity flags

[GHC]

#12822: Cleanup GHC verbosity flags
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        Reporter:  hsyl20            |                Owner:  (none)
            Type:  task              |               Status:  new
        Priority:  low               |            Milestone:
       Component:  Compiler          |              Version:  8.0.1
      Resolution:                    |             Keywords:
                                     |  newcomer,flags
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  Other             |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by bgamari):

 For the record, here are the relevant uses of `verbosity` that I was able
 to quickly find,
 {{{
 $ ag "verbosity .*dflags"
 compiler/backpack/DriverBkp.hs
 514:                | verbosity (hsc_dflags hsc_env) >= 2 -> showMsg
 "Skipping  " ""

 compiler/ghci/Linker.hs
 1463:    = when (verbosity dflags > 1) $

 compiler/main/Finder.hs
 659:        | verbosity dflags < 3 =
 775:        | verbosity dflags < 3 =

 compiler/main/DynFlags.hs
 1998:             || (verbosity dflags >= 4 && enableIfVerbose f)
 2203:  | verbosity dflags >= 4 = ["-v"]

 compiler/main/HscMain.hs
 810:            | verbosity (hsc_dflags hsc_env) >= 2 -> showMsg "Skipping
 " ""

 compiler/main/ErrUtils.hs
 554:  | verbosity dflags >= val = act
 613:       if verbosity dflags >= 2
 684: = do   { let verb = verbosity dflags

 ghc/Main.hs
 233:  case verbosity dflags6 of
 736:   let verb = verbosity dflags

 ghc/GHCi/UI.hs
 553:                when (isNothing maybe_exprs && verbosity dflags > 0) $
 588:  let show_prompt = verbosity dflags > 0 || is_tty
 618:  liftIO $ when (verbosity dflags > 0) $ putStrLn "Leaving GHCi."
 1818:  when (verbosity dflags > 0) $
 2634:          when (verbosity dflags2 > 0) $
 }}}

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/12822#comment:8>
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