PATCH: [perl #116787] -Ox on Win64 Visual C 64 bit is flawed, switch to -O1

-Ox is missing -GF and -Gy and -Gs
http://blogs.msdn.com/b/branbray/archive/2005/07/08/437078.aspx
http://msdn.microsoft.com/en-us/library/8f8h5cxt%28v=vs.90%29.aspx
http://msdn.microsoft.com/en-us/library/59a3b321%28v=vs.90%29.aspx

So the remaining question is, use -O1 or use -O2 on VC 64? VC 32 bit uses
-O1, and that is also slightly faster on x64 too.