Needed for sys-fs/udev.
This might be a problem. I said stabilisation would be okay but keywording is a different matter. patchelf is known not to work on arm and I have seen this for myself. I have no idea about the other arches. I suggest you do runtime testing here but if it's not going to work for arm then you may have to resort to some other tool. https://github.com/NixOS/patchelf/issues/8
I updated udev to use chrpath instead. Thanks for the heads-up.