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
[2]: https://en.wikipedia.org/wiki/HP-UX
[3]: https://en.wikipedia.org/wiki/Itanium