[GHC] #13105: Allow type families in RuntimeReps

[GHC]

#13105: Allow type families in RuntimeReps
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        Reporter:  goldfire          |                Owner:
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.0.1
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
                                     |  typecheck/should_fail/T13105
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Changes (by goldfire):

 * testcase:   => typecheck/should_fail/T13105


Comment:

 I've added a test case (in my work on #12809, at Phab:D2842), but it's a
 `compile_fail` test, just because code like this originally made my branch
 panic. It doesn't panic now, and I want to keep it that way until this bug
 is addressed properly.

 Fixing this bug should make the test succeed.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13105#comment:1>
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