Error code E0587

A type has both packed and align representation hints.

Erroneous code example:

#![allow(unused)] fn main() { #[repr(packed, align(8))] // error! struct Umbrella(i32); }

You cannot use packed and align hints on a same type. If you want to pack a type to a given size, you should provide a size to packed:

#![allow(unused)] fn main() { #[repr(packed(8))] // ok! struct Umbrella(i32); }