[GHC] #13292: Type checker rejects ambiguous top level declaration.

[GHC]

#13292: Type checker rejects ambiguous top level declaration.
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        Reporter:  jeiea             |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler (Type    |              Version:  8.0.2
  checker)                           |
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:  x86_64
                                     |  (amd64)
 Type of failure:  Other             |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by Simon Peyton Jones <simonpj@…>):

 In [changeset:"3c62b1d6b672e7727ea5fa56c69bf43e43d0fd8f/ghc"
 3c62b1d6/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="3c62b1d6b672e7727ea5fa56c69bf43e43d0fd8f"
 Gather constraints locally in checkMain

 Wiwth -fdefer-type-errors we were generating some top-level
 equality constraints, just in a corner of checkMain.  The
 fix is easy.

 Fixes Trac #13292
 }}}

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13292#comment:7>
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