[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:  goldfire
            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:
  valid program                      |                Blocking:
      Blocked By:                    |  Differential Revisions:
 Related Tickets:                    |
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Changes (by ekmett):

 * cc: ekmett (added)


Comment:

 Thanks, Simon.

 We've constructed a workaround for now, but this is pretty much the last
 thing we have in the way of shedding 117 performance-motivated
 `unsafeCoerce`'s in favor of `coerce`. =)

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10079#comment:4>
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