As mentioned elsewhere, a different design is being pursued. In addition, lots of similar changes have already landed as part of the Rust-in-Linux work, which has many of the same needs.
In addition, Rust doesn't require you to use allocation, ever. It was originally expected that users who can't handle allocation failures would eschew libstd in favor of libcore (a subset of libstd with all the allocating parts removed).
In addition, Rust doesn't require you to use allocation, ever. It was originally expected that users who can't handle allocation failures would eschew libstd in favor of libcore (a subset of libstd with all the allocating parts removed).