[GHC] #8835: 7.6.3 vs 7.8-RC performance regression

[GHC]

#8835: 7.6.3 vs 7.8-RC performance regression
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        Reporter:  cbm80                    |            Owner:
            Type:  bug                      |           Status:  new
        Priority:  normal                   |        Milestone:
       Component:  Compiler                 |          Version:  7.8.1-rc2
      Resolution:                           |         Keywords:
Operating System:  Linux                    |     Architecture:  x86_64
 Type of failure:  Runtime performance bug  |  (amd64)
       Test Case:                           |       Difficulty:  Unknown
        Blocking:                           |       Blocked By:
                                            |  Related Tickets:
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Comment (by thoughtpolice):

 `-fno-full-laziness` makes exactly 0 difference on this program. I can see
 some of the differences in Core, but I haven't made out exactly what the
 problem is yet.

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8835#comment:2>
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