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// ignore-wasm32-bare always compiled as panic=abort right now and this requires unwinding
// This test checks that instantiating an uninhabited type via `mem::{uninitialized,zeroed}` results
// in a runtime panic.
#![feature(never_type)]
use std::{mem, panic};
#[allow(dead_code)]
struct Foo {
x: u8,
y: !,
}
enum Bar {}
fn main() {
unsafe {
assert_eq!(
panic::catch_unwind(|| {
mem::uninitialized::<!>()
}).err().and_then(|a| a.downcast_ref::<String>().map(|s| {
s == "Attempted to instantiate uninhabited type !"
})),
Some(true)
);
assert_eq!(
panic::catch_unwind(|| {
mem::zeroed::<!>()
}).err().and_then(|a| a.downcast_ref::<String>().map(|s| {
s == "Attempted to instantiate uninhabited type !"
})),
Some(true)
);
assert_eq!(
panic::catch_unwind(|| {
mem::MaybeUninit::<!>::uninit().assume_init()
}).err().and_then(|a| a.downcast_ref::<String>().map(|s| {
s == "Attempted to instantiate uninhabited type !"
})),
Some(true)
);
assert_eq!(
panic::catch_unwind(|| {
mem::uninitialized::<Foo>()
}).err().and_then(|a| a.downcast_ref::<String>().map(|s| {
s == "Attempted to instantiate uninhabited type Foo"
})),
Some(true)
);
assert_eq!(
panic::catch_unwind(|| {
mem::zeroed::<Foo>()
}).err().and_then(|a| a.downcast_ref::<String>().map(|s| {
s == "Attempted to instantiate uninhabited type Foo"
})),
Some(true)
);
assert_eq!(
panic::catch_unwind(|| {
mem::MaybeUninit::<Foo>::uninit().assume_init()
}).err().and_then(|a| a.downcast_ref::<String>().map(|s| {
s == "Attempted to instantiate uninhabited type Foo"
})),
Some(true)
);
assert_eq!(
panic::catch_unwind(|| {
mem::uninitialized::<Bar>()
}).err().and_then(|a| a.downcast_ref::<String>().map(|s| {
s == "Attempted to instantiate uninhabited type Bar"
})),
Some(true)
);
assert_eq!(
panic::catch_unwind(|| {
mem::zeroed::<Bar>()
}).err().and_then(|a| a.downcast_ref::<String>().map(|s| {
s == "Attempted to instantiate uninhabited type Bar"
})),
Some(true)
);
assert_eq!(
panic::catch_unwind(|| {
mem::MaybeUninit::<Bar>::uninit().assume_init()
}).err().and_then(|a| a.downcast_ref::<String>().map(|s| {
s == "Attempted to instantiate uninhabited type Bar"
})),
Some(true)
);
}
}
|
