[GHC] #12951: Remove __USE_MINGW_ANSI_STDIO define from PosixSource.h

[GHC]

#12951: Remove __USE_MINGW_ANSI_STDIO define from PosixSource.h
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        Reporter:  bgamari           |                Owner:
            Type:  task              |               Status:  new
        Priority:  normal            |            Milestone:  8.4.1
       Component:  Compiler          |              Version:  8.0.1
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):  Phab:D2812
       Wiki Page:                    |
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Comment (by Ben Gamari <ben@…>):

 In [changeset:"6da62535469149d69ec98674db1c51dbde0efab1/ghc"
 6da62535/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="6da62535469149d69ec98674db1c51dbde0efab1"
 rts/PosixSource.h: Define __USE_MINGW_ANSI_STDIO on Windows

 This was removed in 8dc72f3c33b0e724ddb690c9d494969980c10afd which cleaned
 up
 PosixSource.h. Strangely, this only started breaking for me now.

 Test Plan: Validate on Windows

 Reviewers: simonmar, erikd, austin, Phyx

 Reviewed By: Phyx

 Subscribers: thomie

 Differential Revision: https://phabricator.haskell.org/D2812

 GHC Trac Issues: #12951
 }}}

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/12951#comment:2>
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