As per bug 602126, elfutils is not available for musl, and libelf is used in stead. Currently AFAICT, it is masked on MIPS musl profiles, but not for other arches. eroen@occam ~ $ grep -r libelf /usr/portage/profiles/ ... /usr/portage/profiles/default/linux/musl/package.mask:>virtual/libelf-2 ... eroen@occam /usr/local/portage/media-gfx/synfig $ find /usr/portage/profiles/ -name parent -exec grep musl {} + ... /usr/portage/profiles/hardened/linux/musl/mips/mipsel/parent:../../../../../default/linux/musl/mips/mipsel /usr/portage/profiles/hardened/linux/musl/mips/parent:../../../../default/linux/musl/mips
We removed the mask and everyone using musl should be using the musl overlay which means you would have a working elfutils. This is needed for newer kernel releases.