When building with the latest Rust release, 1.81.0, a future incompatibility warning is raised at the end of the build:

warning: the following packages contain code that will be rejected by a future version of Rust: ra_ap_stdx v0.0.188

There are newer versions of this crate available. We can try updating to see if this behavior has been fixed in a newer release, otherwise we should report it upstream to rust analyzer (if it hasn't been already).