src/liballoc/tests/heap.rs


1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34

use std::alloc::{Global, Alloc, Layout, System};

/// Issue #45955 and #62251.
#[test]
fn alloc_system_overaligned_request() {
    check_overalign_requests(System)
}

#[test]
fn std_heap_overaligned_request() {
    check_overalign_requests(Global)
}

fn check_overalign_requests<T: Alloc>(mut allocator: T) {
    for &align in &[4, 8, 16, 32] { // less than and bigger than `MIN_ALIGN`
        for &size in &[align/2, align-1] { // size less than alignment
            let iterations = 128;
            unsafe {
                let pointers: Vec<_> = (0..iterations).map(|_| {
                    allocator.alloc(Layout::from_size_align(size, align).unwrap()).unwrap()
                }).collect();
                for &ptr in &pointers {
                    assert_eq!((ptr.as_ptr() as usize) % align, 0,
                               "Got a pointer less aligned than requested")
                }

                // Clean up
                for &ptr in &pointers {
                    allocator.dealloc(ptr, Layout::from_size_align(size, align).unwrap())
                }
            }
        }
    }
}