[rustc.git] / src / test / ui / init-large-type.rs

// compile-flags: -O
// run-pass

#![allow(unused_must_use)]
// Makes sure that zero-initializing large types is reasonably fast,
// Doing it incorrectly causes massive slowdown in LLVM during
// optimisation.

// pretty-expanded FIXME #23616
// ignore-emscripten no threads support

#![feature(intrinsics)]

use std::{mem, thread};

const SIZE: usize = 1024 * 1024;

fn main() {
    // do the test in a new thread to avoid (spurious?) stack overflows
    thread::spawn(|| {
        let _memory: [u8; SIZE] = unsafe { mem::zeroed() };
    }).join();
}
Commit	Line	Data
ba9703b0	1	// compile-flags: -O
416331ca XL	2	// run-pass
416331ca XL	3
0bf4aa26	4	#![allow(unused_must_use)]
85aaf69f SL	5	// Makes sure that zero-initializing large types is reasonably fast,
	6	// Doing it incorrectly causes massive slowdown in LLVM during
	7	// optimisation.
223e47cc	8
c34b1796	9	// pretty-expanded FIXME #23616
7453a54e	10	// ignore-emscripten no threads support
85aaf69f	11
b7449926	12	#![feature(intrinsics)]
c34b1796	13
ba9703b0	14	use std::{mem, thread};
223e47cc	15
85aaf69f SL	16	const SIZE: usize = 1024 * 1024;
	17
	18	fn main() {
	19	// do the test in a new thread to avoid (spurious?) stack overflows
9346a6ac	20	thread::spawn(\|\| {
ba9703b0	21	let _memory: [u8; SIZE] = unsafe { mem::zeroed() };
85aaf69f	22	}).join();
223e47cc	23	}