[GHC] #13458: Panic with unsafeCoerce and -dcore-lint

[GHC]

#13458: Panic with unsafeCoerce and -dcore-lint
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        Reporter:  dfeuer            |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  highest           |            Milestone:  8.2.1
       Component:  Compiler (Type    |              Version:  8.1
  checker)                           |             Keywords:
      Resolution:                    |  LevityPolymorphism
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  Compile-time      |            Test Case:
  crash or panic                     |  typecheck/should_compile/T13458
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Changes (by rwbarton):

 * owner:  goldfire => (none)
 * priority:  normal => highest
 * status:  closed => new
 * resolution:  fixed =>


Comment:

 This cure is worse than the disease was--Core Lint now seems to warn about
 *every* unsafe coercion; and the volume of warnings produced during the
 build of ghc somehow broke https://perf.haskell.org/ghc/. Can we revert
 this for now?

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13458#comment:16>
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