Implement ptr::fn_addr_eq · patricklam/verify-rust-std@62d240d (original) (raw)
`@@ -2130,6 +2130,33 @@ pub fn addr_eq<T: ?Sized, U: ?Sized>(p: *const T, q: *const U) -> bool {
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`(p as *const ()) == (q as *const ())
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`}
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``
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/// Compares the addresses of the two function pointers for equality.
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///
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/// Function pointers comparisons can have surprising results since
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/// they are never guaranteed to be unique and could vary between different
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/// code generation units. Furthermore, different functions could have the
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/// same address after being merged together.
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///
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/// This is the same as f == g but using this function makes clear
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/// that you are aware of these potentially surprising semantics.
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///
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/// # Examples
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///
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/// ```
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/// #![feature(ptr_fn_addr_eq)]
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/// use std::ptr;
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///
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/// fn a() { println!("a"); }
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/// fn b() { println!("b"); }
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/// assert!(!ptr::fn_addr_eq(a as fn(), b as fn()));
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/// ```
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#[unstable(feature = "ptr_fn_addr_eq", issue = "129322")]
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#[inline(always)]
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#[must_use = "function pointer comparison produces a value"]
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pub fn fn_addr_eq<T: FnPtr, U: FnPtr>(f: T, g: U) -> bool {
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f.addr() == g.addr()
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}
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`/// Hash a raw pointer.
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`///
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`` /// This can be used to hash a &T reference (which coerces to *const T implicitly)
``