Comment by phil-opp

There is some minimal support for fallible allocation through the try_reserve method on various collections. See https://github.com/rust-lang/rust/issues/48043 for more information.

Other than that, there is ongoing work for custom allocator support in collections: https://github.com/rust-lang/rust/issues/42774. Maybe that's what you meant with tracking the allocators at the type level?

It's of course also possible to create own fallible collection types, for example as a wrapper around the normal liballoc and try_reserve.