22 lines
710 B
Rust
22 lines
710 B
Rust
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#![feature(rustc_attrs, const_let, const_fn)]
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use std::cell::Cell;
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#[rustc_layout_scalar_valid_range_start(1)]
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#[repr(transparent)]
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pub(crate) struct NonZero<T>(pub(crate) T);
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fn main() {}
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const fn foo() -> NonZero<Cell<u32>> {
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let mut x = unsafe { NonZero(Cell::new(1)) };
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let y = &x.0; //~ ERROR cannot borrow a constant which may contain interior mutability
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//~^ ERROR borrow of layout constrained field with interior mutability
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unsafe { NonZero(Cell::new(1)) }
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}
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const fn bar() -> NonZero<Cell<u32>> {
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let mut x = unsafe { NonZero(Cell::new(1)) };
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let y = unsafe { &x.0 }; //~ ERROR cannot borrow a constant which may contain interior mut
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unsafe { NonZero(Cell::new(1)) }
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}
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