[GHC] #13754: ghc-8.0.2+ rejects more instance declarations

[GHC]

#13754: ghc-8.0.2+ rejects more instance declarations
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        Reporter:  zilinc            |                Owner:  (none)
            Type:  bug               |               Status:  closed
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.0.1
      Resolution:  invalid           |             Keywords:
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 zilinc):

 Replying to [comment:4 simonpj]:
 > >  So shall I conclude it's a bug which has been fixed in GHC-8.0.2
 >
 > More "it wasn't a bug in the first place".
 >

 Sorry I don't get you then --- why it's not rejected by earlier (<8.0.2)
 versions of GHC? Can you please give some hints? If I hadn't tried
 GHC-8.0.2 I would never uncover this bug in my program.

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13754#comment:5>
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