Unlike C++, Rust doesn’t allow mutable memory aliasing. That’s because mutable aliasing can never happen in Safe Rust, and not supporting it improves performance. This means that when writing Unsafe Rust, one has to be careful about aliasing.

Note though that it’s perfectly fine to have multiple mutable raw pointers pointing to the same data, as long as there’s no ownership held by any Rust code. The problem only happens if you try to convert them into references.