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// Copyright 2013 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.
#![feature(never_type)]
#![feature(exhaustive_patterns, rustc_attrs)]
#![warn(unreachable_code)]
#![warn(unreachable_patterns)]
enum Void {}
impl From<Void> for i32 {
fn from(v: Void) -> i32 {
match v {}
}
}
fn bar(x: Result<!, i32>) -> Result<u32, i32> {
x?
}
fn foo(x: Result<!, i32>) -> Result<u32, i32> {
let y = (match x { Ok(n) => Ok(n as u32), Err(e) => Err(e) })?;
//~^ WARN unreachable pattern
//~| WARN unreachable expression
Ok(y)
}
fn qux(x: Result<u32, Void>) -> Result<u32, i32> {
Ok(x?)
}
fn vom(x: Result<u32, Void>) -> Result<u32, i32> {
let y = (match x { Ok(n) => Ok(n), Err(e) => Err(e) })?;
//~^ WARN unreachable pattern
Ok(y)
}
#[rustc_error]
fn main() { //~ ERROR: compilation successful
let _ = bar(Err(123));
let _ = foo(Err(123));
let _ = qux(Ok(123));
let _ = vom(Ok(123));
}
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