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//@ check-fail
//
// issue: <https://github.com/rust-lang/rust/issues/120217>
#![feature(arbitrary_self_types_pointers)]
trait Static<'a> {
fn proof(self: *const Self, s: &'a str) -> &'static str;
}
fn bad_cast<'a>(x: *const dyn Static<'static>) -> *const dyn Static<'a> {
x as _ //~ error: lifetime may not live long enough
}
impl Static<'static> for () {
fn proof(self: *const Self, s: &'static str) -> &'static str {
s
}
}
fn extend_lifetime(s: &str) -> &'static str {
bad_cast(&()).proof(s)
}
fn main() {
let s = String::from("Hello World");
let slice = extend_lifetime(&s);
println!("Now it exists: {slice}");
drop(s);
println!("Now it’s gone: {slice}");
}
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