issue-28950.rs

// Copyright 2012-2016 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.

// ignore-emscripten
// compile-flags: -O

// Tests that the `vec!` macro does not overflow the stack when it is
// given data larger than the stack.

// FIXME(eddyb) Improve unoptimized codegen to avoid the temporary,
// and thus run successfully even when compiled at -C opt-level=0.

const LEN: usize = 1 << 15;

use std::thread::Builder;

fn main() {
    assert!(Builder::new().stack_size(LEN / 2).spawn(|| {
        // FIXME(eddyb) this can be vec![[0: LEN]] pending
        // https://llvm.org/bugs/show_bug.cgi?id=28987
        let vec = vec![unsafe { std::mem::zeroed::<[u8; LEN]>() }];
        assert_eq!(vec.len(), 1);
    }).unwrap().join().is_ok());
}