Linus Torvalds: Speaks on the Rust vs C Linux Divide
Linus Torvalds Speaks on the the divide between Rust and C Linux developers an the future Linux. Will things like fragmentation among the open source community hurt the Linux Kernel? We'll listen to the Creator of Linux.
I took notes for the benefit of anyone who doesn't like their info in video form. My attempt to summarize what Linus says:
He enjoys the arguments, it's nice that Rust has livened up the discussion. It shows that people care.
It's more contentious than it should be sometimes with religious overtones reminiscent of vi versus emacs. Some like it, some don't, and that's okay.
Too early to see if Rust in the kernel ultimately fails or succeeds, that will take time, but he's optimistic about it.
The kernel is not normal C. They use tools that enforce rules that are not part of the language, including memory safety infrastructure. This has been incrementally added over a long time, which is what allowed people to do it without the kind of outcry that the Rust efforts produce by trying to change things more quickly.
There aren't many languages that can deal with system issues, so unless you want to use assembler it's going to be C, C-like, or Rust. So probably there will be some systems other than Linux that do use Rust.
If you make your own he's looking forward to seeing it.
Nor does Forth (which used to be a common choice for "first thing to bootstrap on this new chip architecture we have no real OS for yet"). Alas, they're just not popular languages these days.
Zig is indeed designed specifically for such tasks as system programming and interoperability with C code. However it is not yet ready for production usage as necessary infrastructure is not yet done and each new version introduces breaking changes. Developers recomend waiting version 1.0 before using it in any serious project.
Zig is feasible for systems programming and some, (most notably, the Primeagen in one video) claim it should have gone into the kernel instead of Rust, but I don't know Zig so I don't feel qualified to comment beyond that.
Linus did have emotion control issues and was not always completely rational, but he's gone a long way towards being incredibly responsible to his child that powers the world.
Also, he long understands that Linux ain't a hobby project, which some programmers still get to think.
FWIW, it's a 9 min video and doesn't contain anything earth shattering or easily summarized. Basically there is some friction between C and Rust devs, and Linus doesn't think that it's such a bad thing (there has be interesting discussion) and it's way too early to call Rust in the kernel a failure.
I also dont like videos for this stuff. Summarized using kagi's universal summarizer, sharing here:
The integration of Rust into the Linux kernel has been a contentious topic, with some long-term maintainers resisting the changes required for memory-safe Rust code.
The debate over Rust vs. C in the Linux kernel has taken on "almost religious overtones" in certain areas, reflecting the differing design philosophies and expectations.
Linus Torvalds sees the Rust discussion as a positive thing, as it has "livened up some of the discussions" and shows how much people care about the kernel.
Not everyone in the kernel community understands everything about the kernel, and specialization is common - some focus on drivers, others on architectures, filesystems, etc. The same is true for Rust and C.
Linus does not think the Rust integration is a failure, as it's still early, and even if it were, that's how the community learns and improves.
The challenge is that Rust's memory-safe architecture requires changes to the existing infrastructure, which some long-time maintainers, like the DRM subsystem people, are resistant to.
The Linux kernel has developed a lot of its own memory safety infrastructure over time for C, which has allowed incremental changes, whereas the Rust changes are more "in your face."
Despite the struggles with Rust integration, Linus believes Linux is so widely used and entrenched that alternative "bottom-up grown-up from the start Rust kernels" are unlikely to displace it.
Linus sees the embedded/IoT space as an area where alternative kernels built around different languages like Rust may emerge, but does not see Linux losing its dominance as a general-purpose OS.
Overall, Linus views the Rust debate as a positive sign of the community's passion and an opportunity to learn, even if the integration process is challenging.
This video is full of jarring edits which initially made me wonder if someone had cut out words or phrases to create an abbreviated version. But, then I realized there are way too many of them to have been done manually. I checked the full original video and from the few edits i manually checked it seems like it is just inconsequential pauses etc that were removed: for instance, when Linus says "the other side of that picture" in the original there is an extra "p" sound which is removed here.
Yet another irritating and unnecessary application of neural networks, I guess.
If you believe in ADTs, limiting mutation, & a type system that goes beyond Rust’s affine types + lack of refinements (including a interleaved proof system), you could be writing kernel code in ATS which compiles to C.