[GHC] #9109: Improve error messages around "untouchable" type variables

[GHC]

#9109: Improve error messages around "untouchable" type variables
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              Reporter:  goldfire    |            Owner:
                  Type:  bug         |           Status:  closed
              Priority:  normal      |        Milestone:  7.10.1
             Component:  Compiler    |          Version:  7.8.2
            Resolution:  fixed       |         Keywords:
      Operating System:              |     Architecture:  Unknown/Multiple
  Unknown/Multiple                   |       Difficulty:  Unknown
       Type of failure:              |       Blocked By:
  None/Unknown                       |  Related Tickets:
             Test Case:              |
  typecheck/should_fail/T9109        |
              Blocking:              |
Differential Revisions:              |
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Changes (by goldfire):

 * status:  new => closed
 * testcase:   => typecheck/should_fail/T9109
 * resolution:   => fixed


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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9109#comment:7>
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