[GHC] #16392: In ghci, revertCAFs should be executed in the external interpreter when necessary

[GHC]

#16392: In ghci, revertCAFs should be executed in the external interpreter when
necessary
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        Reporter:  lolotp            |                Owner:  lolotp
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  GHCi              |              Version:  8.6.3
      Resolution:                    |             Keywords:  newcomer
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |  https://gitlab.haskell.org/ghc/ghc/merge_requests/500
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Comment (by Marge Bot <ben+marge-bot@…>):

 In [changeset:"7a68254a7284db5bf8f1fa82aba4a6825d8f050a/ghc"
 7a68254a/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="7a68254a7284db5bf8f1fa82aba4a6825d8f050a"
 Fix #16392: revertCAFs in external interpreter when necessary

 We revert CAFs when loading/adding modules in ghci (presumably to refresh
 execution states and to allow for object code to be unloaded from the
 runtime).
 However, with `-fexternal-interpreter` enabled, we are only doing it in
 the
 ghci process instead of the external interpreter process where the cafs
 are
 allocated and computed. This makes sure that revertCAFs is done in the
 appropriate process no matter if that flag is present or not.
 }}}

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/16392#comment:5>
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