If you're talking about Rust codebases, I'm pretty sure that writing sound unsafe code is at least feasible. It's not easy, and it should be avoided if at all possible, but saying that 100% of those codebases are unsound is pessimistic.
replyOne feasible approach is to use "storytelling" as described here: https://www.ralfj.de/blog/2026/03/13/inline-asm.html That's talking about inline assembly, but in principle any other unsafe feature could be similarly modeled.
It's not impossible, it is just highly unlikely that you'll never write a single safety-related bug - especially in nontrivial applications and in mixed C-plus-Rust codebases. For every single bug-free codebase there will be thousands containing undiscovered subtle-but-usually-harmless bugs.
replyAfter all, if humans were able to routinely write bug-free code, why even worry about unsoundness and UB in C? Surely having developers write safe C code would be easier than trying to get a massive ecosystem to adopt a completely new and not exactly trivial programming language?
Rust is not really "completely new" for a good C/C++ coder, it just cleans up the syntax a bit (for easier machine-parsing) and focuses on enforcing the guidelines you need to write safe code. This actually explains much of its success. The fact that this also makes it a nice enough high-level language for the Python/Ruby/JavaScript etc. crowd is a bit of a happy accident, not something that's inherent to it.
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