[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):

 I am starting to receive bug reports for the packages I maintain (these
 are the bindings for gtk and other libraries autogenerated by
 http://github.com/haskell-gi/haskell-gi) from people running into this
 issue. Is there some workaround I could apply to avoid the panic?

 I would be happy to help fixing the bug properly, of course, but I have
 not clue where to start, and that would in any case not help for the
 crashes with the already released 8.2.1.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13981#comment:9>
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