[GHC] #12433: GHCi produces incorrect results when evaluating with compiled code

[GHC]

#12433: GHCi produces incorrect results when evaluating with compiled code
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        Reporter:  diatchki          |                Owner:  simonmar
            Type:  bug               |               Status:  new
        Priority:  highest           |            Milestone:  8.0.2
       Component:  Compiler          |              Version:  8.0.1
      Resolution:                    |             Keywords:  ghci, dynamic
                                     |  linking, compiled code
Operating System:  Linux             |         Architecture:  x86_64
 Type of failure:  Incorrect result  |  (amd64)
  at runtime                         |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):  Phab:D2529
       Wiki Page:                    |
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Comment (by Simon Marlow <marlowsd@…>):

 In [changeset:"86836a2ecc089b917866a2cb65b716fd5f04cc56/ghc" 86836a2/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="86836a2ecc089b917866a2cb65b716fd5f04cc56"
 Fix codegen bug in PIC version of genSwitch (#12433)

 Summary:
 * getNonClobberedReg instead of getSomeReg, because the reg needs to
   survive across t_code
 * Use a new reg for the table offset calculation instead of clobbering
   the reg returned by expr (this was the bug affecting #12433)

 Test Plan: New unit test; validate

 Reviewers: rwbarton, bgamari, austin, erikd

 Subscribers: thomie

 Differential Revision: https://phabricator.haskell.org/D2529

 GHC Trac Issues: #12433
 }}}

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/12433#comment:13>
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