[GHC] #15346: Core Lint error in GHC 8.6.1: From-type of Cast differs from type of enclosed expression

[GHC]

#15346: Core Lint error in GHC 8.6.1: From-type of Cast differs from type of
enclosed expression
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        Reporter:  RyanGlScott       |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:  8.6.1
       Component:  Compiler (Type    |              Version:  8.5
  checker)                           |
      Resolution:                    |             Keywords:  TypeInType
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Compile-time      |  Unknown/Multiple
  crash or panic                     |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by Ryan Scott <ryan.gl.scott@…>):

 In [changeset:"6595bee749ddb49d9058ed47ab7c1b6e7558ae17/ghc" 6595bee/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="6595bee749ddb49d9058ed47ab7c1b6e7558ae17"
 Define an Outputable MCoercion instance

 Summary: I needed this when debugging #15346.

 Test Plan: Does it compile? It does? Cool.

 Reviewers: bgamari, mpickering

 Reviewed By: mpickering

 Subscribers: rwbarton, thomie, carter

 GHC Trac Issues: #15311

 Differential Revision: https://phabricator.haskell.org/D4944
 }}}

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15346#comment:9>
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