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#![feature(rustc_attrs)]
#[rustc_layout_scalar_valid_range_start(1)]
#[repr(transparent)]
pub(crate) struct NonZero<T>(pub(crate) T);
fn main() {
}
const fn foo() -> NonZero<u32> {
let mut x = unsafe { NonZero(1) };
let y = &mut x.0;
//~^ ERROR mutation of layout constrained field is unsafe
unsafe { NonZero(1) }
}
const fn bar() -> NonZero<u32> {
let mut x = unsafe { NonZero(1) };
let y = unsafe { &mut x.0 };
unsafe { NonZero(1) }
}
const fn boo() -> NonZero<u32> {
let mut x = unsafe { NonZero(1) };
unsafe { let y = &mut x.0; }
unsafe { NonZero(1) }
}
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