[GHC] #14047: "Illegal instance for type synonym" while deriving Typeable1 for data type

[GHC]

#14047: "Illegal instance for type synonym" while deriving Typeable1 for data type
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        Reporter:  alexbiehl         |                Owner:  (none)
            Type:  bug               |               Status:  patch
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.2.1
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:  #13267            |  Differential Rev(s):  Phab:D3817
       Wiki Page:                    |
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Comment (by Ryan Scott <ryan.gl.scott@…>):

 In [changeset:"a81b5b0067b6530f5883aeb0154a407a54d14c62/ghc"
 a81b5b00/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="a81b5b0067b6530f5883aeb0154a407a54d14c62"
 Remove the deprecated Typeable{1..7} type synonyms

 Summary:
 `Typeable{1..7}` (type synonyms for the poly-kinded `Typeable`) have
 been deprecated since GHC 7.8. They're now causing problems for users who
 try
 to still work with them in legacy code, since they can no longer be used
 in
 instances. To avoid this sort of confusion, let's just remove
 `Typeable{1..7}`
 altogether. Resolves #14047.

 Reviewers: bgamari, austin, hvr

 Reviewed By: bgamari

 Subscribers: rwbarton, thomie

 GHC Trac Issues: #14047

 Differential Revision: https://phabricator.haskell.org/D3817
 }}}

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14047#comment:6>
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