[GHC] #15384: Every implication should bump the TcLevel exactly once

[GHC]

#15384: Every implication should bump the TcLevel exactly once
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        Reporter:  goldfire          |                Owner:  (none)
            Type:  task              |               Status:  new
        Priority:  normal            |            Milestone:  8.6.1
       Component:  Compiler          |              Version:  8.5
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by Krzysztof Gogolewski <krz.gogolewski@…>):

 In [changeset:"b202e7a48401bd8e805a92dcfe5ea059cbd8e41c/ghc"
 b202e7a4/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="b202e7a48401bd8e805a92dcfe5ea059cbd8e41c"
 Fix the TcLevel not being set correctly when finding valid hole fits

 Summary:
 This fixes the problem revealed by a new assert as it relates to valid
 hole fits. However, tests `T10384`, `T14040a` and `TcStaticPointersFail02`
 still fail the assert, but they are unrelated to valid hole fits.

 Reviewers: bgamari, simonpj

 Reviewed By: simonpj

 Subscribers: simonpj, rwbarton, thomie, carter

 GHC Trac Issues: #15384

 Differential Revision: https://phabricator.haskell.org/D4994
 }}}

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15384#comment:8>
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