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37 lines
981 B
Rust
37 lines
981 B
Rust
// compile-flags: -Zunleash-the-miri-inside-of-you
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use std::cell::UnsafeCell;
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// a test demonstrating what things we could allow with a smarter const qualification
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// this is fine because is not possible to mutate through an immutable reference.
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static FOO: &&mut u32 = &&mut 42;
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// this is fine because accessing an immutable static `BAR` is equivalent to accessing `*&BAR`
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// which puts the mutable reference behind an immutable one.
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static BAR: &mut () = &mut ();
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struct Foo<T>(T);
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// this is fine for the same reason as `BAR`.
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static BOO: &mut Foo<()> = &mut Foo(());
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// interior mutability is fine
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struct Meh {
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x: &'static UnsafeCell<i32>,
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}
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unsafe impl Sync for Meh {}
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static MEH: Meh = Meh {
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x: &UnsafeCell::new(42),
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};
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// this is fine for the same reason as `BAR`.
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static OH_YES: &mut i32 = &mut 42;
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fn main() {
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unsafe {
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*MEH.x.get() = 99;
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}
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*OH_YES = 99; //~ ERROR cannot assign to `*OH_YES`, as `OH_YES` is an immutable static item
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}
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