[GHC] #14607: Core Lint error

[GHC]

#14607: Core Lint error
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        Reporter:  Iceland_jack      |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.2.2
      Resolution:                    |             Keywords:  TypeInType,
                                     |  DeferredTypeErrors
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:  #14605 #14584     |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by Simon Peyton Jones <simonpj@…>):

 In [changeset:"9e5535ca667e060ce1431d42cdfc3a13ae080a88/ghc"
 9e5535ca/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="9e5535ca667e060ce1431d42cdfc3a13ae080a88"
 Fix OptCoercion

 In the presence of -fdefer-type-errors, OptCoercion can
 encounter a mal-formed coerercion with type
     T a ~ T a b
 and that was causing a subsequent Lint error.

 This caused Trac #14607.  Easily fixed by turning an ASSERT
 into a guard.
 }}}

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14607#comment:4>
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