Enum can't work as expected.

[rise0chen]

#[derive(Debug, Clone, Copy, PartialEq, Eq)]
 #[repr(align(2))]
pub enum Test {
    A,
    B(u8),
}

Test::A maybe is 0x0000 or 0xXX00, so it maybe not equal when transmute to u16.

[Amanieu]

You're right, enums will not work with this crate. Only types which have no paddings bytes and no invalid values will work. This effectively constraints it to structs with no padding bytes.

[rise0chen]

#[repr(align(4))]
pub struct Test {
    a: u8,
    b: u16,
}

Does this struct have paddings bytes?

[Amanieu]

Yes it does.