I can't speak for OpenBSD specifically but I can speak to some of my thoughts in why an operating system continues to use C. Supporting a language ecosystem is not easy, the less "default" languages needed to bootstrap the core system the better. The nice part about C is that it's one of the few languages suited for both kernel space and user space. Out of the alternatives you listed the only language that could even seriously be considered for kernel space is rust, and even that took a lot of back and forth to get it to that point in the Linux kernel. Higher level languages have a larger range as assumptions and you have to tow those accomodations in to kernel space if you want to use them. There is also the issue of the memory management in kernel space being much more of a complicated environment than user space. How do I teach the borrow checker about my MMU bring up and maintenance?
I am also skeptical to your claim about removing memory bugs freeing up brain space for logic bugs, at least for Rust. Rust has grown quite a number of language features, that in my experience, result in a higher cognitive load compared to C. If you seriously reduce your reliance on the C macro system (as Plan
9 has shown possible), the language itself is quite simple.
I am also skeptical to your claim about removing memory bugs freeing up brain space for logic bugs, at least for Rust. Rust has grown quite a number of language features, that in my experience, result in a higher cognitive load compared to C. If you seriously reduce your reliance on the C macro system (as Plan 9 has shown possible), the language itself is quite simple.