https://issues.dlang.org/show_bug.cgi?id=15959

          Issue ID: 15959
           Summary: core.sys.windows modules should be modified for x64
           Product: D
           Version: D2
          Hardware: x86_64
               URL: https://msdn.microsoft.com/en-us/library/aa383663(v=vs
                    .85).aspx
                OS: Windows
            Status: NEW
          Severity: major
          Priority: P1
         Component: druntime
          Assignee: nobody@puremagic.com
          Reporter: jiki@red.email.ne.jp

core.sys.windows.* modules came with 2.070.
However, their support for x64 are not enough,
then some of those API's need modified.

The above MSDN link is the list of the APIs affected by x64.
(I've been searching for it!)

I'll send a PR later.

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