[GHC] #12040: Code that builds on 7.8.4 and 7.10.3 but fails with requiring UndecidableInstances on 8.0.1-rc4

[GHC]

#12040: Code that builds on 7.8.4 and 7.10.3 but fails with requiring
UndecidableInstances on 8.0.1-rc4
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        Reporter:  dmcclean          |                Owner:
            Type:  bug               |               Status:  closed
        Priority:  normal            |            Milestone:
       Component:  Compiler (Type    |              Version:  8.0.1
  checker)                           |
      Resolution:  invalid           |             Keywords:
Operating System:  Linux             |         Architecture:
 Type of failure:  GHC rejects       |  Unknown/Multiple
  valid program                      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Changes (by simonpj):

 * status:  new => closed
 * resolution:   => invalid


Comment:

 OK -- thanks for raising it though.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/12040#comment:9>
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