rust/tests/ui/impl-trait/unsafety-checking-cycle.rs

33 lines
745 B
Rust

// Ensure that we don't get a cycle error from trying to determine whether an
// opaque type implements `Freeze` in safety checking, when it doesn't matter.
//@ check-pass
#![feature(rustc_attrs)]
struct AnyValue<T>(T);
// No need to check for `Freeze` here, there's no
// `rustc_layout_scalar_valid_range_start` involved.
fn not_restricted(c: bool) -> impl Sized {
if c {
let x = AnyValue(not_restricted(false));
&x.0;
}
2u32
}
#[rustc_layout_scalar_valid_range_start(1)]
struct NonZero<T>(T);
// No need to check for `Freeze` here, we're not borrowing the field.
fn not_field(c: bool) -> impl Sized {
if c {
let x = unsafe { NonZero(not_field(false)) };
&x;
}
5u32
}
fn main() {}