[GHC] #14223: Casts get in the way of join points

[GHC]

#14223: Casts get in the way of join points
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        Reporter:  nomeata           |                Owner:  (none)
            Type:  task              |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.2.1
      Resolution:                    |             Keywords:  JoinPoints
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by simonpj):

 Hmm.

 IF you float the `letrec go` inside the cast you'd get
 {{{
 (letrec go = ... in go xs) |> blah
 }}}
 Now `go` is indeed a join point, and will be turned into a join point.
 And then the `|> blah` continuation will move into its RHS (becuase it's a
 join point).

 So really it should work fine right now.  I wonder why that does not
 happen?

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14223#comment:1>
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