Again, from what I understand, `restrict` is not enough to convey everything Rust knows. Further, those other languages may be nothing like C, but they're even

Again, from what I understand, `restrict` is not enough to convey everything Rust knows. Further, those other languages may be nothing like C, but they're even less like Rust. So because of its heritage, even given the information Rust knows, LLVM simply doesn't have the optimization passes to take full advantage of it.