[GHC] #15418: Performance drop 60 times on non-profiling binary

[GHC]

#15418: Performance drop 60 times on non-profiling binary
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        Reporter:  hth313            |                Owner:  (none)
            Type:  bug               |               Status:  infoneeded
        Priority:  high              |            Milestone:  8.8.1
       Component:  Runtime System    |              Version:  8.4.3
      Resolution:                    |             Keywords:
Operating System:  MacOS X           |         Architecture:  x86_64
 Type of failure:  Runtime           |  (amd64)
  performance bug                    |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:  #14414, #9599     |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by Simon Marlow <marlowsd@…>):

 In [changeset:"d00c308633fe7d216d31a1087e00e63532d87d6d/ghc"
 d00c3086/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="d00c308633fe7d216d31a1087e00e63532d87d6d"
 Fix for recover with -fexternal-interpreter (#15418)

 Summary:
 When using -fexternal-interpreter, recover was not treating a Q
 compuation that simply registered an error with addErrTc as failing.

 Test Plan:
 New unit tests:
 * T15418 is the repro from in the ticket
 * TH_recover_warns is a new test to ensure that we're keeping warnings
 when
   the body of recover succeeds.

 Reviewers: bgamari, RyanGlScott, angerman, goldfire, erikd

 Subscribers: rwbarton, carter

 GHC Trac Issues: #15418

 Differential Revision: https://phabricator.haskell.org/D5185
 }}}

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15418#comment:20>
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