[GHC] #15666: Dependent type synonym in recursive type family causes GHC to panic

[GHC]

#15666: Dependent type synonym in recursive type family causes GHC to panic
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        Reporter:  tydeu             |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:  8.6.1
       Component:  Compiler          |              Version:  8.4.3
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Compile-time      |  Unknown/Multiple
  crash or panic                     |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:  #15380            |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by Ryan Scott <ryan.gl.scott@…>):

 In [changeset:"2a9ceadfa07e2298ce934c6d304a3ba1f529ad93/ghc" 2a9cead/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="2a9ceadfa07e2298ce934c6d304a3ba1f529ad93"
 Add regression test for #15666

 Commit 59f38587d44efd00b10a6d98f6a7a1b22e87f13a ended up
 fixing #15666. Let's add a regression test to ensure that it stays
 fixed.
 }}}

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15666#comment:8>
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