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// NOTE: Exposing the bug encoded in this test is sensitive to
// LLVM optimization choices. See additional note below for an
// example.
#[link(name = "bad")]
extern "C" {
pub fn c_read_value(a: u32, b: u32, c: u32) -> u16;
}
fn main() {
const C1: usize = 0x327b23c6;
const C2: usize = C1 & 0xFFFF;
let r1: usize = 0x0;
let r2: usize = C1;
let r3: usize = 0x0;
let value: u16 = unsafe { c_read_value(r1 as u32, r2 as u32, r3 as u32) };
// NOTE: as an example of the sensitivity of this test to optimization choices,
// uncommenting this block of code makes the bug go away on pnkfelix's machine.
// (But observing via `dbg!` doesn't hide the bug. At least sometimes.)
/*
println!("{}", value);
println!("{}", value as usize);
println!("{}", usize::from(value));
println!("{}", (value as usize) & 0xFFFF);
*/
let d1 = value;
let d2 = value as usize;
let d3 = usize::from(value);
let d4 = (value as usize) & 0xFFFF;
let d = (&d1, &d2, &d3, &d4);
let d_ = (d1, d2, d3, d4);
assert_eq!(((&(C2 as u16), &C2, &C2, &C2), (C2 as u16, C2, C2, C2)), (d, d_));
}
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