alt Hacker NewsI would summarize it thusly: Rust is roughly as performant as C. This matches my experience and Rust is more ergonomic than C in many regards. The caveat is that modern C++ is notably more performant than C and by implication Rust. This also matches my experience for both C and Rust.
I think most of this is attributable to the ergonomics of compile-time expressiveness. C++ can effortlessly do things that require mountains of ugly boilerplate and macros in C or Rust. In principle they can express the same things but no one wants to write or deal with that ugly boilerplate so the equivalency is never realized in real code bases.
Zig is interesting because it slots in as a C-like language with a competent and expressive compile-time story. I don’t use Zig but I recognize its game.
Is C++ more performant than C? I find this hard to believe. C++ does not have any construct that cannot be replicated, or is not common, in C. The only candidate is using virtualization and void* pointers instead of monomorphized generics which some C code does for the lack of better options, but that's not a problem in Rust as well.
If anything, Rust has the potential to be more performant than C due to its aliasing rules (C has `restrict` but it's rarely used, standard C++ does not have even that). The current perf stats show it does make Rust code faster but just a little bit, although we don't utilize the full optimization potential currently (LLVM does not do many possible optimizations here, and `noalias` is weaker than Rust's aliasing rules). It can also affect autovectorization, and if it does the effect could be dramatic.