[GHC] #16038: Simplifier incorrectly breaks recursive groups

[GHC]

#16038: Simplifier incorrectly breaks recursive groups
-------------------------------------+-------------------------------------
        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:                    |
-------------------------------------+-------------------------------------

Comment (by Ömer Sinan Ağacan <omeragacan@…>):

 In [changeset:"8adef36cb16b244a81dfb54ead924e00069f33ae/ghc"
 8adef36c/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="8adef36cb16b244a81dfb54ead924e00069f33ae"
 Add test for #16038
 }}}

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/16038#comment:7>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler