Many software depends on
glibc itself or
glibc macroses or just
glibc style so build fails. You can fix any software easy if you know
glibc from inside. For example we can see here linux headers for
musl. Headers are not finished but you can checkout commits and see how this work looks like.
Every developer tests its software using
glibc based system. It is not possible to fix all live software development and make it compatible with other
libc using right solution like pull request. So general purpose systems like
gentoo can't be build using alternative libc without infinite pain.
Embedded developers (from
openwrt for example) are fixing software versions and making a heavy work around it. So embedded system (like
openwrt) only can provide a source that can be build with alternative libc like
The only painless and right way to replace
glibc with other
libc is to implement special wrapper that simulates all
glibc behaviours using other
libc. There is no such project today.