spooky.rs

use std::mem;
use std::ptr;

fn spooky(_data: &[f32; 3]) {
  // This function does nothing. Calling it should have no effect on the program.
}

pub fn main() {
  let data1 = [1.0, 2.0, 3.0];
  let data2 = [1.0, 2.0, 3.0];

  spooky(&data2);

  unsafe {
    let bytes1: [u8; 12] = ptr::read(mem::transmute(&data1));
    let bytes2: [u8; 12] = ptr::read(mem::transmute(&data2));

    println!("{}", bytes1 == bytes2); // Prints "false"; prints "true" if line 12 is commented out.
  }
}