Well since me and you use Gentoo (we have to compile ourself using ebuilds). I don't know much about Debian. But usually when creating a deb file, you compile yourself and what not, same with rpm. But that's what i'd do. Create package manager's package. And for the ones you have to compile yourself. Go with what they ship with their distro out of the box. But more usually it's GCC-4.2.x to GCC-4.3.x.