[GHC] #15226: GHC doesn't know that seq# produces something in WHNF

[GHC]

#15226: GHC doesn't know that seq# produces something in WHNF
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        Reporter:  dfeuer            |                Owner:  (none)
            Type:  bug               |               Status:  merge
        Priority:  normal            |            Milestone:  8.6.1
       Component:  Compiler          |              Version:  8.4.3
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Runtime           |  Unknown/Multiple
  performance bug                    |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):  Phab:D4796
       Wiki Page:                    |
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Comment (by simonpj):

 > We should (I believe) rewrite

 Yes -- this is a variant of the case binder-swap in `OccurAnal`.  See
 `Note [Binder swap]` in `OccurAnal`.  This is the place to do it.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15226#comment:7>
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