rust/src/test/ui/lint/packed_reference.rs

#![deny(packed_references)]

#[repr(packed)]
pub struct Good {
    data: &'static u32,
    data2: [&'static u32; 2],
    aligned: [u8; 32],
}

fn main() {
    unsafe {
        let good = Good { data: &0, data2: [&0, &0], aligned: [0; 32] };

        let _ = &good.data; //~ ERROR reference to packed field
        let _ = &good.data as *const _; //~ ERROR reference to packed field
        let _: *const _ = &good.data; //~ ERROR reference to packed field
        let _ = &good.data2[0]; //~ ERROR reference to packed field
        let _ = &*good.data; // ok, behind a pointer
        let _ = &good.aligned; // ok, has align 1
        let _ = &good.aligned[2]; // ok, has align 1
    }
}