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#![feature(rustc_attrs)]
use std::cell::Cell;
#[rustc_layout_scalar_valid_range_start(1)]
#[repr(transparent)]
pub(crate) struct NonZero<T>(pub(crate) T);
fn main() {
let mut x = unsafe { NonZero(Cell::new(1)) };
match x {
NonZero(ref x) => { x }
//~^ ERROR borrow of layout constrained field with interior mutability
};
let mut y = unsafe { NonZero(42) };
match y { NonZero(ref y) => { y } }; // OK, type of `y` is freeze
match y { NonZero(ref mut y) => { y } };
//~^ ERROR mutation of layout constrained field
}
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