[GHC] #14490: TTG Snags

[GHC]

#14490: TTG Snags
-------------------------------------+-------------------------------------
        Reporter:  alanz             |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.3
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:  #14482            |  Differential Rev(s):
       Wiki Page:                    |
  ImplementingTreesThatGrow          |
-------------------------------------+-------------------------------------

Comment (by alanz):

 Having just leveled up on `Turtle`, the compile time differences for
 compiling stage2 (via `-ddump-timings`) are attached, together with the
 programme used to generate them.

 The key result is the following
 {{{
 Module        :      master                  reverted
 diff
 HsSyn         :    10154.82                   1550.70
 8604.12
 HsImpExp      :    16266.68                   4703.24
 11563.44
 DynFlags      :    70682.66                  59097.39
 11585.27
 HsLit         :    21915.48                   4487.74
 17427.74
 HsPat         :    26660.85                   7181.77
 19479.08
 HsTypes       :   107182.37                  16066.12
 91116.25
 HsBinds       :   115097.57                  19346.81
 95750.76
 HsExpr        :   260980.84                  38087.04
 222893.79
 HsDecls       :   320157.08                  45702.17
 274454.90
 }}}

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14490#comment:21>
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