[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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Comment (by Richard Eisenberg <eir@…>):

 In [changeset:"befe2d7c8902096dd184ebca3f7f135ee5f479e8/ghc"]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="befe2d7c8902096dd184ebca3f7f135ee5f479e8"
 Fix #10079 by recurring after flattening exposes a TyConApp.

 Previously, try_decompose_nom_app was smart enough to recur if
 flattening exposed a TyConApp, but try_decompose_repr_app was
 not. Now, if neither type in try_decompose_repr_app is an AppTy,
 recur.

 Seems all straightforward enough to avoid a Note.
 }}}

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10079#comment:7>
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