Comment by superkuh
9 hours ago
When a language changes significantly faster than release cycles (ie, rust being a different compiler every 3 months) it means that distros cannot self-host if they use rust code in their software. ie, with Debian's Apt now having rust code, and Debian's release cycle being 4 years for LTS, Debian's shipped rustc won't be able to compile Apt since nearly all rust devs are bleeding edge targeters. The entire language culture is built around this rapid improvement.
I love that C++ has a long enough time between changing targets to actually be useful and that it's culture is about stability and usefulness for users trying to compile things rather than just dev-side improvements uber alles.
The problem you mention is perhaps a sign that the model Debian uses is ill suited for development. Stable software is great but it need not impede progress and evolution. It's also possible to support older rust compiler versions if it's important - apt developers can do the work necessary to support 4yo lts compilers.
> Debian's shipped rustc won't be able to compile Apt since nearly all rust devs are bleeding edge targeters.
This is nonsense. Apt devs can target a rustc release and that release can be the same release that ships with Debian? Moreover, since those apt devs may have some say in the matter, they can choose to update the compiler in Debian!
> The entire language culture is built around this rapid improvement.
... Because this is a cultural argument about how some people really enjoy having their codebase be 6 years behind the latest language standard, not about any actual practical problem.
And I can understand how someone may not be eager to learn C++20's concepts or to add them immediately to a code base, but upgrades to your minimum Rust version don't really feel like that. It's much more like "Wow that's a nifty feature, I immediately understand and I'd like to use in the std lib. That's a great alternative to [much more complex thing...]" See, for example, OnceLock added at 1.70.0: https://doc.rust-lang.org/std/sync/struct.OnceLock.html