[GHC] #11770: Demand analysis: Wrong one-shot annotation due to fixed-point iteration

[GHC]

#11770: Demand analysis: Wrong one-shot annotation due to fixed-point iteration
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        Reporter:  nomeata           |                Owner:
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.1
      Resolution:                    |             Keywords:
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 nomeata):

 >  No, that'll be fine: the occurrence analyser runs before each pass of
 the simplifier.

 Aha, the OccurAnal code actually looks at `idDemandInfo` of a let-bound
 expression. Didn’t know that, but it makes sense now. I’ll add that to the
 relevant note.

 >  Good point! Please comment this prominently with updOneShotInfo.

 Done, in `wip/T11770` for now.

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11770#comment:5>
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