rustc optimization check

main.rs

#[no_mangle]
pub fn a_function(arg_1: &mut u32, arg_2: &mut u32) -> u32 {
// pub fn a_function(arg_1: &mut u32) {
    *arg_1 = 10;
    *arg_2 = 11;

    *arg_2
}

fn main() {
    let mut a: u32 = 0;
    let mut b: u32 = 0;
    a_function(&mut a, &mut b);
}

makefile

build:
	rustc main.rs -O --emit=obj
	objdump -D main.o | less