[GHC] #15472: GHC HEAD type inference regression post-"Remove decideKindGeneralisationPlan"

[GHC]

#15472: GHC HEAD type inference regression post-"Remove
decideKindGeneralisationPlan"
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        Reporter:  RyanGlScott       |                Owner:  (none)
            Type:  bug               |               Status:  closed
        Priority:  highest           |            Milestone:  8.8.1
       Component:  Compiler (Type    |              Version:  8.5
  checker)                           |
      Resolution:  invalid           |             Keywords:  TypeInType
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  GHC rejects       |  Unknown/Multiple
  valid program                      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by RyanGlScott):

 If you can successfully find a smaller program than this which exhibits
 the same issue, then I applaud you. But the original program is small
 enough that it may be worth checking in under a `should_fail` directory
 somewhere in the test suite.

 Also, we should mention this in the GHC 8.8 migration guide
 (https://ghc.haskell.org/trac/ghc/wiki/Status/GHC-8.8.1).

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15472#comment:5>
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