Drop on `await` point

i guess a way that could work is a recursive auto trait that is mutually exclusive with Future ? that's a bit strange. should it cover Coroutine s as well ?

I currently don't propose any implementation path, but as a general idea. And yes, Coroutine as well.

can you name some ? currently there is no way to ensure one is not held across an await point afaik

Mostly mutexes do rely on the fact that they are not held across await points, to prevent deadlocks. Clippy even has lints against it, like Clippy Lints .