util: use <ptr>::addr instead of unsafe impl

[mattiapitossi]

Motivation

I noticed that there are a couple of unsafe impl of the pointer's addr method in the code. Was wondering if we want to replace with addr since it's stable from v1.84.

Solution

Replace unsafe { std::mem::transmute(ptr) }; with <ptr>::addr method.

[ADD-SP]

Shall we use expose_provenance and std::ptr::with_exposed_provenance?

[mattiapitossi]

Hi @ADD-SP, it looks like that the -Zmiri-strict-provenance flag prevents to use with_exposed_provenance API. I reverted the commit (see: https://github.com/tokio-rs/tokio/actions/runs/19196647091/job/54878644730)

[Darksonn]

The entire point of this file is to avoid using expose_provenance so that Tokio can run with -Zmiri-strict-provenance. So we should not switch to expose_provenance.

[Darksonn]

Thanks.