[GHC] #10251: Bad rule generated in pathological cases

[GHC]

#10251: Bad rule generated in pathological cases
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        Reporter:  simonpj           |                   Owner:
            Type:  bug               |                  Status:  new
        Priority:  normal            |               Milestone:
       Component:  Compiler          |                 Version:  7.10.1
      Resolution:                    |                Keywords:
Operating System:  Unknown/Multiple  |            Architecture:
 Type of failure:  None/Unknown      |  Unknown/Multiple
      Blocked By:                    |               Test Case:
 Related Tickets:                    |                Blocking:
                                     |  Differential Revisions:
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Comment (by Simon Peyton Jones <simonpj@…>):

 In [changeset:"cfb60421a43f23e75ead85d99cec207a156f9312/ghc"]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="cfb60421a43f23e75ead85d99cec207a156f9312"
 Do not quantify over the function itself in a RULE

 We were erroneously quantifying over the function when it
 had a dictionary type. A bit pathological, but possible.

 This fixes Trac #10251
 }}}

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10251#comment:2>
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