This is a wild #rust toolchain bug:Can only repro when the call to gettid is in a library crate, and only when it has a certain name, and only when not using -C target-feature=-crt-static, only when using LTO... The boundary is exactly at std! Crate names alphabetically ≥ std fail (including std itself), and crate names < std work!https://github.com/rust-lang/rust/issues/154439