[GHC] #15795: Core lint error with unused kind variable in data type return kind

[GHC]

#15795: Core lint error with unused kind variable in data type return kind
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        Reporter:  Iceland_jack      |                Owner:  (none)
            Type:  bug               |               Status:  closed
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.6.1
      Resolution:  fixed             |             Keywords:  TypeInType
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
                                     |  tests/polykinds/T15795, T15795a
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by Richard Eisenberg <rae@…>):

 In [changeset:"17bd163566153babbf51adaff8397f948ae363ca/ghc"
 17bd1635/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="17bd163566153babbf51adaff8397f948ae363ca"
 Visible kind application

 Summary:
 This patch implements visible kind application (GHC Proposal 15/#12045),
 as well as #15360 and #15362.
 It also refactors unnamed wildcard handling, and requires that type
 equations in type families in Template Haskell be
 written with full type on lhs. PartialTypeSignatures are on and warnings
 are off automatically with visible kind
 application, just like in term-level.

 There are a few remaining issues with this patch, as documented in
 ticket #16082.

 Includes a submodule update for Haddock.

 Test Plan: Tests T12045a/b/c/TH1/TH2, T15362, T15592a

 Reviewers: simonpj, goldfire, bgamari, alanz, RyanGlScott, Iceland_jack

 Subscribers: ningning, Iceland_jack, RyanGlScott, int-index, rwbarton,
 mpickering, carter

 GHC Trac Issues: `#12045`, `#15362`, `#15592`, `#15788`, `#15793`,
 `#15795`, `#15797`, `#15799`, `#15801`, `#15807`, `#15816`

 Differential Revision: https://phabricator.haskell.org/D5229
 }}}

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15795#comment:9>
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