src/test/ui/lint/unused_braces_borrow.rs

// check-pass
// run-rustfix

#![warn(unused_braces)]

// changing `&{ expr }` to `&expr` changes the semantic of the program
// so we should not warn this case

#[repr(packed)]
pub struct A {
    pub a: u8,
    pub b: u32,
}

fn consume<T>(_: T) {}

fn main() {
    let a = A {
        a: 42,
        b: 1729,
    };

    consume(&{ a.b });
    consume({ a.b });
    //~^ WARN unnecessary braces
}