Currently emerge --depclean --ignore-soname-deps=n will abort due to a broken soname dependency, like this example from bug 563744: * Dependencies could not be completely resolved due to * the following required packages not being installed: * * x86_32: libc.so.6 pulled in by: * dev-lang/go-1.4.2 Generally, broken soname dependencies can safely be suppressed by a REQUIRES_EXCLUDE setting in the ebuild, so they should only trigger a warning message.
There's a patch in the following branch: https://github.com/zmedico/portage/tree/bug_563844 I've posted it for review here: https://archives.gentoo.org/gentoo-portage-dev/message/47f1065e449ce5234efe983831c3ecb9
This is in the master branch: https://gitweb.gentoo.org/proj/portage.git/commit/?id=aca25ac8ceb854713057c75c40d1a96fa764ca79
Released in 2.2.24.