src/test/ui/union/union-lint-dead-code.rs


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// Copyright 2016 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.

#![deny(dead_code)]

union Foo {
    x: usize,
    b: bool, //~ ERROR: field is never used
    _unused: u16,
}

fn field_read(f: Foo) -> usize {
    unsafe { f.x }
}

fn main() {
    let _ = field_read(Foo { x: 2 });
}