[GHC] #15276: Bogus type in typechecker error recovery

[GHC]

#15276: Bogus type in typechecker error recovery
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        Reporter:  simonpj           |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:  8.6.1
       Component:  Compiler          |              Version:  8.4.3
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by Simon Peyton Jones <simonpj@…>):

 In [changeset:"807ab222d08c11a4d00064c9835f9ed9f20ffc7c/ghc" 807ab22/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="807ab222d08c11a4d00064c9835f9ed9f20ffc7c"
 Fix the bind-recovery type

 This patch uses (forall (a::*). a) for the type to
 use when recovering from an error in a binding.

 Previously (Trac #15276) we had (forall r (a :: TYPE r). a),
 which is ill-kinded.

 It's quite hard to provoke an error arising from this, because
 it only happens in programs that have a type error anyway,
 but in a subequent patch I make typeKind fall over if it returns
 an ill-scoped kind, and that makes ghci/scripts/T13202 crash
 without this fix.
 }}}

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15276#comment:1>
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