[GHC] #10218: GHC creates incorrect code which throws <<loop>>

[GHC]

#10218: GHC creates incorrect code which throws <<loop>>
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        Reporter:  yongqli           |                   Owner:
            Type:  bug               |                  Status:  new
        Priority:  normal            |               Milestone:
       Component:  Compiler          |                 Version:  7.10.1
      Resolution:                    |                Keywords:
Operating System:  Unknown/Multiple  |            Architecture:
 Type of failure:  None/Unknown      |  Unknown/Multiple
      Blocked By:                    |               Test Case:  yes
 Related Tickets:                    |                Blocking:
                                     |  Differential Revisions:
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Comment (by AlexET):

 I have simplified the example further.

 The difference between the working and not working cases is now really
 small.

 I think the simplifier core is mostly equal (modulo alpha). However the
 demand analysis is different. The core-prep also has a case in one which
 is a let in the other. The stg differ similarly. The cmm differs more (but
 the difference between a case and a let would cause a larger difference
 there).

 In terms of flags currently I know that specialise ,funbox-strict-fields
 and static-argument-transformation are uneeded. cse, strictness are
 needed. I will try more later.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10218#comment:5>
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