[GHC] #10031: coerce can cause compiler to loop

[GHC]

#10031: coerce can cause compiler to loop
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        Reporter:  glguy             |                   Owner:  goldfire
            Type:  bug               |                  Status:  new
        Priority:  normal            |               Milestone:
       Component:  Compiler          |                 Version:  7.10.1-rc1
      Resolution:                    |                Keywords:
Operating System:  Unknown/Multiple  |            Architecture:  x86_64
 Type of failure:  Compile-time      |  (amd64)
  crash                              |               Test Case:
      Blocked By:                    |                Blocking:
 Related Tickets:                    |  Differential Revisions:  Phab:D630
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Comment (by Richard Eisenberg <eir@…>):

 In [changeset:"cecf036fa10830a5e9861d1e6a2f8c22059fb4bb/ghc"]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="cecf036fa10830a5e9861d1e6a2f8c22059fb4bb"
 Fix #10031 by inverting a critical test in kick_out.

 Summary:
 The documentation (Note [The flattening story] in TcFlatten) was
 correct; it's just the implementation that was not.

 Test in typecheck/should_compile/T10031

 Test Plan: validate

 Reviewers: austin

 Subscribers: thomie

 Differential Revision: https://phabricator.haskell.org/D630

 GHC Trac Issues: #10031
 }}}

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10031#comment:6>
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