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


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// 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;
    }
}