Docs don't show that pointer::is_null() is defined only where T: Sized

[Ms2ger]

No description provided.

[KamilaBorowska]

To clarify the issue, documentation says (there is also similar implementation for mut pointers):

impl<T> *const T where T: ?Sized

But that doesn't match the actual implementation where T has to be Sized.

[durka]

There's a T: ?Sized on the impl, but the actual function puts back T: Sized and the docs don't reflect this.

This doesn't seem to happen in a normal project with a similar impl: where T: Sized is correctly shown on the fn.

[bluss]

Looks like the usual cross crate doc inclusion issue. The methods are defined in core.

[Kixunil]

I've just encountered this issue. Example.

Any explanation why T must impl Sized? What's the correct approach to null-check in case of unsized types?

[Mark-Simulacrum]

Closing as a duplicate of #24183.