pub const SIZE: isize = 4; #[repr(C)] pub struct WithoutAs { items: [char; SIZE as usize], } #[repr(C)] pub struct WithAs { items: [char; SIZE as usize], } // dummy function to make `WithoutAs` and `WithAs` part of the public api #[no_mangle] pub extern fn some_fn(a: WithoutAs, b: WithAs) { }