[GHC] #11744: Latest Xcode update violates POSIX compliance of `nm -P`

[GHC]

#11744: Latest Xcode update violates POSIX compliance of `nm -P`
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        Reporter:  hvr           |                Owner:
            Type:  bug           |               Status:  new
        Priority:  highest       |            Milestone:
       Component:  Build System  |              Version:
      Resolution:                |             Keywords:
Operating System:  MacOS X       |         Architecture:  Unknown/Multiple
 Type of failure:  None/Unknown  |            Test Case:
      Blocked By:                |             Blocking:
 Related Tickets:                |  Differential Rev(s):  phab:D2113
       Wiki Page:                |
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Comment (by Ben Gamari <ben@…>):

 In [changeset:"bf17fd0e5b5442a87f507b26e64a30c79732838a/ghc"
 bf17fd0e/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="bf17fd0e5b5442a87f507b26e64a30c79732838a"
 deriveConstants: Verify sanity of nm

 Add a sanity check ensuring that nm emits valid hexadecimal output, as
 required by POSIX. See #11744 for motivation.

 Reviewers: austin, bgamari

 Subscribers: thomie

 Differential Revision: https://phabricator.haskell.org/D2113

 GHC Trac Issues: #11744
 }}}

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11744#comment:14>
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