Change:
In 1.35, 's requires , but in 1.36-beta it requires . Both are auto-derived, so it must be a change in their internals. Obviously, is quite different than the old implementation. ! ! Ditto for . I'm not sure if there's any real impact in this, but it should be considered, and perhaps audit for other similar changes. cc as discussed on IRC.
This is fixed in hashbrown 0.4.0.
Shouldn't be fixed as well?
Since is actually based on , it derives the same constraints.
Ah, gotcha. Thanks! Sorry for the false alarm :).
I think it would be a good idea to add a run-pass to check that these auto-trait impls don't change again.
might make sense to add them as tests to most collections. , , etc. don't have tests for these either. I've made this error in some of my collections (changing some internal implementation detail and breaking users that rely on auto traits working "like before").

Discussion:
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