[GHC] #11473: Levity polymorphism checks are inadequate

[GHC]

#11473: Levity polymorphism checks are inadequate
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        Reporter:  simonpj           |                Owner:  goldfire
            Type:  bug               |               Status:  new
        Priority:  highest           |            Milestone:  8.0.1
       Component:  Compiler          |              Version:  7.10.3
      Resolution:                    |             Keywords:
                                     |  LevityPolymorphism, TypeInType
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Incorrect         |  Unknown/Multiple
  warning at compile-time            |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by Richard Eisenberg <eir@…>):

 In [changeset:"5d98b8bf249fab9bb0be6c5d4e8ddd4578994abb/ghc"
 5d98b8bf/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="5d98b8bf249fab9bb0be6c5d4e8ddd4578994abb"
 Clean up some pretty-printing in errors.

 It turns out that there were some pretty egregious mistakes
 in the code that suggested -fprint-explicit-kinds, which are
 fixed. This commit also reorders a bunch of error messages,
 which I think is an improvement.

 This also adds the test case for #11471, which is what
 triggered the cleanup in TcErrors. Now that #11473 is done,
 there is nothing more outstanding for #11471.

 test case: dependent/should_fail/T11471
 }}}

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11473#comment:12>
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