`alloc`-only `HashMap`?

Well then, RIP my aspirations of this being a quick and easy fix (I think this sort of inference breakage is technically allowed under semver as a minor version bump, but I expect it'd break too much existing code to be worth it). Is this an area where people are trying to improve the language such that I can wait and this eventually becomes possible? Or is inference never going to be able to handle this change?