[Rd] windows 64-bit package build on 32-bit machine

[Michael Spiegel]

Hello,

Is it possible to build a 64-bit package on a 32-bit machine on
windows? I can cross-compile for x86, x86_64, and ppc on a 32-bit OS X
machine.  And it looks like I could build a 32-bit library on a 64-bit
windows machine.  But it doesn't look possible to build a 64-bit
library on a 32-bit windows machine?

Thanks,
--Michael