rust/tests/compile-fail/assume.rs

#![feature(core_intrinsics)]

fn main() {
    let x = 5;
    unsafe {
        std::intrinsics::assume(x < 10);
        std::intrinsics::assume(x > 1);
        std::intrinsics::assume(x > 42); //~ ERROR constant evaluation error
    //~^ NOTE `assume` argument was false
    }
}