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18 lines
551 B
Rust
18 lines
551 B
Rust
//@ run-pass
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#![feature(ptr_internals, test)]
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extern crate test;
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use test::black_box as b; // prevent promotion of the argument and const-propagation of the result
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use std::ptr::NonNull;
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const DANGLING: NonNull<u32> = NonNull::dangling();
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const CASTED: NonNull<u32> = NonNull::cast(NonNull::<i32>::dangling());
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pub fn main() {
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// Be super-extra paranoid and cast the fn items to fn pointers before blackboxing them.
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assert_eq!(DANGLING, b::<fn() -> _>(NonNull::dangling)());
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assert_eq!(CASTED, b::<fn() -> _>(NonNull::dangling)());
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}
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