64bit cross compilation on 32bit machines

Is it possible to cross compile on 64-bit binaries on my 32-bit box? If so, what options need to be set and extra libraries installed?

Not with the standard packages. You would have to build a cross-compiler.

Postings on the Ubuntu forums talk about compiling with the -m64 option and linking against the gcc-43-multilib and g++4.x-multilib libraries. Do know know if these are available from any of the OpenSuse repositories?

WJG

I don’t know if the 32-bit compiler is built with the 64-bit backend available. I doubt it. There is generally no reason to provide this backend for the vast majority of developers. While 64-bit x86_64 CPUs can execute 32-bit x86 code and therefore the -m32 option is useful, the converse is not true.

And 64-bit processors are not rare or expensive. You will find that many if not most desktops CPUs are already 64-bit capable.