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#![feature(impl_trait_in_assoc_type)]
//@revisions: noopt opt
//@ build-fail
//@[noopt] compile-flags: -Copt-level=0
//@[opt] compile-flags: -O
//! This fails without optimizations, so it should also fail with optimizations.
struct Fail<T>(T);
impl<T> Fail<T> {
const C: () = panic!(); //~ERROR evaluation of `Fail::<i32>::C` failed
}
#[inline(never)]
fn not_called<T>() {
if false {
let _ = Fail::<T>::C;
}
}
#[inline(never)]
fn callit_not(f: impl Fn()) {
if false {
f();
}
}
// Using `Fn` here is important; with `FnOnce` another shim gets involved which somehow makes this
// easier to collect properly.
trait Hideaway {
type T: Fn();
const C: Self::T;
}
impl Hideaway for () {
type T = impl Fn();
const C: Self::T = not_called::<i32>;
}
#[inline(never)]
fn reveal<T: Hideaway>() {
if false {
callit_not(T::C);
}
}
fn main() {
if false {
reveal::<()>()
}
}
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