There's a closed pull request on the void-packages repository

[RFC] Add _FORTIFY_SOURCE impl for musl.
https://github.com/void-linux/void-packages/pull/24254

Description:
Using the `fortify-headers` impl from https://git.2f30.org/fortify-headers/file/README.html , which was recommended in https://wiki.musl-libc.org/open-issues.html#Substitute-for-%3Ccode%3E_FORTIFY_SOURCE%3C/code%3E .

Would definitely require extensive testing, I mostly want to know whether going through this testing is worth it.