RUSTSEC-2020-0037 Misbehaving `HandleLike` implementation can lead to memory safety violation

Unsafe code in ObjectPool has time-of-check to time-of-use TOCTOU bug that can eventually lead to a memory safety violation. ObjectPool and HandlePool implicitly assumes that HandleLike trait methods are pure, i.e., they always return the same value. However, this assumption is unsound since...