That said, Gentoo maintains a couple 32-bit ebuilds on the amd64 portage tree. The only one that comes to mind ATM is “mozilla-firefox-bin”; it’s a 32-bit build of Firefox that streamlines a lot of potential plugin issues.

And yeah, not having the code available for proprietary software is a huge problem. In general, as you say, not too much needs to be done to make 32-bit software work in a 64-bit world, but there’s so much proprietary software out there that is no longer actively developed and that has no source available that will fall to the wayside. Free Software has no such problems!

I occasionally download some old source code with issues with sizeof void * != sizeof int… but it usually only takes me a minute or two to fix them since most with these problems are small. .. or I just compile them -m32 .. but it’s been a long time since I’ve resorted to that.

Linux has had native 64 bit in its ranks since the mid 90s (Thanks to Dec alpha and later, Ultrasparc, and PPC64)… so the x86_64 is build on a mature base. Windows is in a much more difficult position because none of the historic 64 bit platforms it supported were popular enough to work out the bugs, and because virtually everything for windows is propritary coders with a special interest in 64 bit support aren’t able to go around and fix other people’s software like they can in Linux.