rust/tests/ui/mir/mir_alignment_check_i686-pc-windows-msvc.rs

22 lines
695 B
Rust

// run-pass
// only-i686-pc-windows-msvc
// compile-flags: -Copt-level=0 -Cdebug-assertions=yes
// MSVC isn't sure if on 32-bit Windows its u64 type is 8-byte-aligned or 4-byte-aligned.
// So this test ensures that on i686-pc-windows-msvc, we do not insert a runtime check
// that will fail on dereferencing of a pointer to u64 which is not 8-byte-aligned but is
// 4-byte-aligned.
#![feature(strict_provenance)]
fn main() {
let mut x = [0u64; 2];
let ptr: *mut u8 = x.as_mut_ptr().cast::<u8>();
unsafe {
let misaligned = ptr.add(4).cast::<u64>();
assert!(misaligned.addr() % 8 != 0);
assert!(misaligned.addr() % 4 == 0);
*misaligned = 42;
}
}