https://issues.dlang.org/show_bug.cgi?id=19613

          Issue ID: 19613
           Summary: Add Darwin platform macros for dmd?
           Product: D
           Version: D2
          Hardware: x86
                OS: Mac OS X
            Status: NEW
          Severity: enhancement
          Priority: P1
         Component: dmd
          Assignee: nobody@puremagic.com
          Reporter: zoujiaqing@gmail.com

OSX = macOS
Darwin = macOS / iOS / watchOS / tvOS

https://forum.dlang.org/thread/kcqecnuzcohkljhmetgd@forum.dlang.org https://github.com/dlang/dub/issues/1639

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