The people working on this are aware that it poses backcompat problems that don't have obvious solutions. They are looking into non-obvious solutions. https://lcnr.de/blog/2025/11/28/implicit-auto-traits-assoc-t... is the most up-to-date one I'm currently aware of.
replyI'm very probably missing something, but as a user I would definitely expect `Iterator::Item: Move`, but then also that `&{mut} T: Move where T: ?Move`.
replyBut yeah I can see how these bounds are somewhat viral. Thanks!
Here is an example of the problem: https://play.rust-lang.org/?version=stable&mode=debug&editio...
replyImagine if MyTrait comes from core/std. Adding an opt-out bound like ?Sized (or ?Move) is a breaking change for any generic code that relies on Sized/Move. But you want some traits from std to be open for !Move types.