Btw, CMake has the [FindThreads][1] module to automatically link with `-lpthread`/`-pthread` in a platform-agnostic way.
Even after this change in glibc, you may still need to use FindThreads to handle [HP-UX][2] (some of which still run [Itanium][3]!!!).
[1]: https://cmake.org/cmake/help/latest/module/FindThreads.html