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// skip-filecheck
//@ compile-flags: -Zmir-opt-level=1 -Zunsound-mir-opts
//@ ignore-test
// FIXME: the pass is unsound and causes ICEs in the MIR validator
// EMIT_MIR simplify_try_if_let.{impl#0}-append.SimplifyArmIdentity.diff
use std::ptr::NonNull;
pub struct LinkedList {
head: Option<NonNull<Node>>,
tail: Option<NonNull<Node>>,
}
pub struct Node {
next: Option<NonNull<Node>>,
}
impl LinkedList {
pub fn new() -> Self {
Self { head: None, tail: None }
}
pub fn append(&mut self, other: &mut Self) {
match self.tail {
None => {}
Some(mut tail) => {
// `as_mut` is okay here because we have exclusive access to the entirety
// of both lists.
if let Some(other_head) = other.head.take() {
unsafe {
tail.as_mut().next = Some(other_head);
}
}
}
}
}
}
fn main() {
let mut one = LinkedList::new();
let mut two = LinkedList::new();
one.append(&mut two);
}
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