[GHC] #13981: Family instance consistency checks happens too early when hs-boot defined type occurs on LHS

[GHC]

#13981: Family instance consistency checks happens too early when hs-boot defined
type occurs on LHS
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        Reporter:  ezyang            |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:  8.4.1
       Component:  Compiler (Type    |              Version:  8.2.1-rc2
  checker)                           |
      Resolution:                    |             Keywords:  hs-boot
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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Comment (by inaki):

 Replying to [comment:11 ezyang]:
 > I can't look into the problem right now, but if there is another
 minimization that demonstrates the problem, that would be very helpful.
 OK, I'll give it a try again, now that I have a better idea of what's
 going on.



 > Does haskell-gi define type families? If it doesn't, this particular
 issue is unlikely to be the problem.
 Yes, it uses them extensively. In fact, if I remove the type-family
 related code the issue disappears.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13981#comment:12>
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