11.04.2023 15:09, Peter Maydell wrote: ..
Frankly I would prefer to just say "we don't support x32". It's a weird non-standard configuration that as far as I'm aware is very little used. Its stats in the debian popularity-contest graphs peaked at 18 users in 2017, and have mostly been fluctuating between 1 and 3 for the last couple of years: https://popcon.debian.org/stat/sub-x32.png
x32 was a nice idea but it lacked some final steps for it to fly. In my opinion anyway. Its compactness and speed are fantastic, - qemu build is about 10..15% faster with x32 gcc than it is with x86_64 gcc. At the time debian picked it up, it was not very usable b/c too many things didn't work and needed care. Today, much more software actually works on x32. It is more, today with debian multiarch setup, it is possible to install some *parts* of the system to be x32 while the rest being x86_64, either for parts which benefits from x32 the most, or the other way around, main x32 and some parts x86_64. But it *still* lacks some infrastructure in debian, so it is possible to do with stable or testing distribution, - right now it is possible with unstable only. Maybe we can change that for bookworm+. The thing is that now, it is much more complete than it was in 2017, and it'd be really sad if it goes away. x32 reveals some interesting problems in the code such as type misuse, it already helped to find and fix some bugs in some software, - for example in samba, where a pointer was misused to store a time_t (which would break with past-2038 time_t). qemu never said it supports x32, and no one demanded such support from it. It's interesting to have it working there still, I *think*, as long as it does not require extra efforts. I'm fine to maintain the change required to keep it at least buildable on x32 in debian - again as long as it does not require huge efforts.
We're currently planning to deprecate-and-drop 32-bit x86 hosts, which are much more widely used than this. I see no reason why we should care about this oddball failed experiment of an ABI...
Thanks, /mjt
