I tried a handful of such hacks for likely/unlikely annotations on stable, when working on versions of https://crates.io/crates/reciprocal https://crates.io/cra

I tried a handful of such hacks for likely/unlikely annotations on stable, when working on versions of https://crates.io/crates/reciprocal https://crates.io/crates/reciprocal. They all resulted in correct code, but none of them had any impact on basic block ordering (on rust 1.52, I believe).