[GHC] #12176: Failure of bidirectional type inference at the kind level

[GHC]

#12176: Failure of bidirectional type inference at the kind level
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        Reporter:  goldfire          |                Owner:  goldfire
            Type:  bug               |               Status:  closed
        Priority:  normal            |            Milestone:  8.4.1
       Component:  Compiler          |              Version:  8.0.1
      Resolution:  fixed             |             Keywords:  TypeInType
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
                                     |  dependent/should_compile/T12176
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Changes (by alpmestan):

 * cc: alpmestan (added)


Comment:

 I recently ran `./validate --slow` and saw the test for this ticket
 (`T12176`) fail in all 5 ways that it supports. Just like with the test
 for #12442, it fails with:

 {{{
 ghc: panic! (the 'impossible' happened)
   (GHC version 8.5.20180329 for x86_64-unknown-linux):
         ASSERT failed! file compiler/typecheck/TcTyClsDecls.hs, line 1531
 }}}

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/12176#comment:4>
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