alt Hacker NewsI was always told rust uses llvm tokens not produceable by c code to do its magic. Was I informed wrong?
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mmastrac • yesterday at 2:43 PM
There are multiple stages of IR in the compiler, basically
I was always told rust uses llvm tokens not produceable by c code to do its magic. Was I informed wrong?
There are multiple stages of IR in the compiler, basically
You probably misunderstood. C can represent any program's semantics, since it's Turing-complete (modulo finite memory). C can't encode the lifetimes Rust uses, but those get erased during compilation to MIR. This takes MIR from rustc (where borrow checking has been completed and lifetime annotations erased) and outputs C with the same semantics. LLVM doesn't use tokens not produceable by C, but rustc does.