[GHC] #16038: Simplifier incorrectly breaks recursive groups

[GHC]

#16038: Simplifier incorrectly breaks recursive groups
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        Reporter:  osa1              |                Owner:  osa1
            Type:  bug               |               Status:  new
        Priority:  highest           |            Milestone:
       Component:  Compiler          |              Version:  8.6.3
      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 simonpj):

 > I thought we're going to have another 8.6 release to fix #16057, if that
 happens maybe we should include this too?

 Maybe.  I don't think it'd destablise anything.  But nor does it fix any
 bugs that anyone has reported.

 Do you think we could generate bogus code if this is not fixed?  If so, is
 a test case easy to construct?

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/16038#comment:11>
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