[GHC] #11708: Typechecker hangs when checking type families with -ddump-tc-trace turned on

[GHC]

#11708: Typechecker hangs when checking type families with -ddump-tc-trace turned
on
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        Reporter:  kcsongor          |                Owner:  kcsongor
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler (Type    |              Version:  8.1
  checker)                           |             Keywords:  typefamilies
      Resolution:                    |  trace hangs
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Changes (by kcsongor):

 * Attachment "TypeFamilyErrors_4.hs" added.

 Relevant file to reproduce the issue

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11708>
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