[GHC] #14449: Type variables allowed to unify in a partial type signature (PartialTypeSignatures)

[GHC]

#14449: Type variables allowed to unify in a partial type signature
(PartialTypeSignatures)
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        Reporter:  kcsongor          |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler (Type    |              Version:  8.2.1
  checker)                           |
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  GHC accepts       |  Unknown/Multiple
  invalid program                    |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by RyanGlScott):

 This regression was introduced in commit
 15b9bf4ba4ab47e6809bf2b3b36ec16e502aea72 (`Improve typechecking of let-
 bindings`).

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14449#comment:1>
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