alt Hacker Newsmem::forget isn’t the only way you can safely leak a value, you can do it with reference cycles too, right? And there is no way for the compiler to detect that?
Isn’t that why mem::forget is safe, because you can always implement it yourself safely? How do you get around that?
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By doing the same as with `Sized`: Automatically including the `Forget` bound on generic parameters and letting methods that don't need to be able to forget them opt out. That way existing code continues to compile and existing unsafe code doesn't become unsound.
This was my first question too, I don't see anything addressing e.g. the cyclical arc example from the original 'spawn' conversation.
It seems like you have to auto-propagate !Forget, and then make 'anything that be used to logically implement forget', probably most importantly things like Rc take a Forget bound and do it at an edition boundary? But the link mentions none of that...
> mem::forget isn’t the only way you can safely leak a value, you can do it with reference cycles too, right? And there is no way for the compiler to detect that?
But there's an easy solution for that: you make the reference-counted smart pointers require their pointee type to be Forget. It will be like how Arc<T> doesn't implement Send unless <T: Sync>.