Description:
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The phpinfo() output on Windows 8.1 and Windows Server 2012 R2 reports the internal OS build version as 6.2.

This is due to the deprecation of GetVersionEx (which we are using) on these platforms - http://msdn.microsoft.com/en-us/library/windows/desktop/dn302074%28v=vs.85%29.aspx

Once we compile the Windows builds with the Visual Studio 2013 compiler and the Windows 8.1 SDK, _NT_TARGET_VERSION=$(_NT_TARGET_VERSION_LATEST) seems to help. However until then we need a different approach. 

In bug #67407 (PR php-src/691) we already fixed a similar issue for the full Windows version name. Since there is a small performance penalty with that approach already, the attached pull request recycles the result of the windows version name test (although it does not look very elegant).

Test script:
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<?php
  phpinfo(INFO_GENERAL);


Expected result:
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Output contains "build 6.3" on a Windows 8.1/Windows Server 2012 R2 machine.


Actual result:
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Output contains "build 6.2" on a Windows 8.1/Windows Server 2012 R2 machine.