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    /// Creates a new pointer with the given address.
    ///
    /// This performs the same operation as an `addr as ptr` cast, but copies
    /// the *address-space* and *provenance* of `self` to the new pointer.
    /// This allows us to dynamically preserve and propagate this important
    /// information in a way that is otherwise impossible with a unary cast.
    ///
    /// This is equivalent to using [`wrapping_offset`][pointer::wrapping_offset] to offset
    /// `self` to the given address, and therefore has all the same capabilities and restrictions.
    ///
    /// This API and its claimed semantics are part of the Strict Provenance experiment,
    /// see the [module documentation][crate::ptr] for details.
    #[must_use]
    #[inline]
    #[unstable(feature = "strict_provenance", issue = "95228")]
    pub fn with_addr(self, addr: usize) -> Self {
        // FIXME(strict_provenance_magic): I am magic and should be a compiler intrinsic.
        //
        // In the mean-time, this operation is defined to be "as if" it was
        // a wrapping_offset, so we can emulate it as such. This should properly
        // restore pointer provenance even under today's compiler.
        let self_addr = self.addr() as isize;
        let dest_addr = addr as isize;
        let offset = dest_addr.wrapping_sub(self_addr);

        // This is the canonical desugaring of this operation
        self.wrapping_byte_offset(offset)
    }


    /// Creates a new pointer by mapping `self`'s address to a new one.
    ///
    /// This is a convenience for [`with_addr`][pointer::with_addr], see that method for details.
    ///
    /// This API and its claimed semantics are part of the Strict Provenance experiment,
    /// see the [module documentation][crate::ptr] for details.
    #[must_use]
    #[inline]
    #[unstable(feature = "strict_provenance", issue = "95228")]
    pub fn map_addr(self, f: impl FnOnce(usize) -> usize) -> Self {
        self.with_addr(f(self.addr()))
    }