[CMake] "Cannot restore timestamp" error on Windows

[Paul Smith]

On Tue, 2013-04-23 at 15:54 -0700, J Decker wrote:
> do you have antivirus software that you can disable? 

No, there's no special antivirus software on these build servers.  It's
hard to imagine what kind of issue antivirus software would cause, that
would be so intermittent.  Our builds perform this "generate.stamp"
operation over 100 times per build, according to our logs, and only once
in every build or two does it cause a problem.

Cheers!