[GHC] #10079: Coercible solver regression: Couldn't match rep of () with Const () b

[GHC]

#10079: Coercible solver regression: Couldn't match rep of () with Const () b
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        Reporter:  glguy             |                   Owner:
            Type:  bug               |                  Status:  new
        Priority:  highest           |               Milestone:  7.10.1
       Component:  Compiler (Type    |                 Version:  7.10.1-rc1
  checker)                           |                Keywords:
      Resolution:                    |            Architecture:
Operating System:  Unknown/Multiple  |  Unknown/Multiple
 Type of failure:  GHC rejects       |               Test Case:  indexed-
  valid program                      |  types/should_compile/T10079
      Blocked By:                    |                Blocking:
 Related Tickets:                    |  Differential Revisions:
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Changes (by ekmett):

 * priority:  high => highest
 * differential:  Phab:D653 =>


Comment:

 (As an aside the supplied patch now does enable us to build all of lens
 `unsafeCoerce` free.)

 @thoughtpolice, is this actually closed, or just had the current patch
 applied?

 I definitely support finding the "right" fix here.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10079#comment:14>
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