[GHC] #9326: Minor change to list comprehension structure leads to poor performance

[GHC]

#9326: Minor change to list comprehension structure leads to poor performance
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              Reporter:  dfeuer      |            Owner:
                  Type:  bug         |           Status:  closed
              Priority:  normal      |        Milestone:
             Component:  Compiler    |          Version:  7.8.3
            Resolution:  invalid     |         Keywords:
      Operating System:              |     Architecture:  Unknown/Multiple
  Unknown/Multiple                   |       Difficulty:  Unknown
       Type of failure:  Runtime     |       Blocked By:
  performance bug                    |  Related Tickets:
             Test Case:              |
              Blocking:              |
Differential Revisions:              |
-------------------------------------+-------------------------------------
Changes (by dfeuer):

 * status:  new => closed
 * resolution:   => invalid


Comment:

 It looks like the original reporter was able to resolve the problem by
 adding some type signatures to get things specialized earlier.

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9326#comment:4>
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