[GHC] #14566: LiberateCase improvements

[GHC]

#14566: LiberateCase improvements
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           Reporter:  simonpj        |             Owner:  (none)
               Type:  bug            |            Status:  new
           Priority:  normal         |         Milestone:
          Component:  Compiler       |           Version:  8.2.1
           Keywords:                 |  Operating System:  Unknown/Multiple
       Architecture:                 |   Type of failure:  None/Unknown
  Unknown/Multiple                   |
          Test Case:                 |        Blocked By:
           Blocking:                 |   Related Tickets:
Differential Rev(s):                 |         Wiki Page:
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 I was looking at the result of compiling `base:Data/Typeable/Internal`.
 It has a fairly large top-level recursive group of functions, involving
 `mkTrApp`.  In doing so I noticed that `LiberateCase` was duplicating the
 entire top-level blob at a call of a function that was actually just a
 call to `error`. Totally nuts.

 This ticket tracks the problem.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14566>
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