l1_futex.rs uses AtomicU32::new and Ordering::SeqCst but imported neither, so
the crate did not compile:
error[E0433]: cannot find type `Ordering` in this scope (x4)
error[E0433]: cannot find type `AtomicU32` in this scope
Same class as the kernel errors fixed a moment ago: committed first-party code
that does not build, invisible while the package was served from cache. The
relibc bump invalidated the cache and both surfaced in the same run.
Verified: cook redbear-threadtest - successful.
vasilito