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//@ check-pass
#![feature(never_type, exhaustive_patterns)]
#![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)
}
fn main() {
let _ = bar(Err(123));
let _ = foo(Err(123));
let _ = qux(Ok(123));
let _ = vom(Ok(123));
}
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