[GHC] #11462: Use of typechecker plugin erroneously triggers "unbound implicit parameter" error

[GHC]

#11462: Use of typechecker plugin erroneously triggers "unbound implicit parameter"
error
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        Reporter:  kwf               |                Owner:  gridaphobe
            Type:  bug               |               Status:  patch
        Priority:  highest           |            Milestone:  8.0.1
       Component:  Compiler (Type    |              Version:  8.0.1-rc1
  checker)                           |
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  GHC rejects       |  Unknown/Multiple
  valid program                      |            Test Case:  T11462
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):  Phab:D1804
       Wiki Page:                    |
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Comment (by Ben Gamari <ben@…>):

 In [changeset:"835a2a24a605f8e458f57c71aa67e9983593b5e4/ghc"
 835a2a24/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="835a2a24a605f8e458f57c71aa67e9983593b5e4"
 Default non-canonical CallStack constraints

 Test Plan: `make test TEST=T11462`

 Reviewers: austin, bgamari, simonpj

 Reviewed By: simonpj

 Subscribers: thomie

 Projects: #ghc

 Differential Revision: https://phabricator.haskell.org/D1804

 GHC Trac Issues: #11462
 }}}

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11462#comment:4>
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