An issue was discovered in the scottqueue crate through 2020-11-15 for Rust. There are unconditional implementations of Send and Sync for Queue<T>.
https://rustsec.org/advisories/RUSTSEC-2020-0133.html
https://raw.githubusercontent.com/rustsec/advisory-db/main/crates/scottqueue/RUSTSEC-2020-0133.md