Since collision-protect makes harmless collisions fatal, the documentation should strongly discourage using it. The protect-owned feature is much more friendly, which is why protect-owned is enabled by default.
In fact, the current (portage-3.0.59) make.conf manpage says: > collision-protect > >> A QA-feature to ensure that a package doesn’t overwrite files it doesn’t own. >> The COLLISION_IGNORE variable can be used to selectively disable this feature. >> Also see the related protect-owned feature. Nothing about recommended-or-not there. But see protect-owned as suggested: > protect-owned > >> [...] >> It is recommended to leave either protect-owned or collision-protect enabled >> at all times, since otherwise file collisions between packages may result >> in files being overwritten or uninstalled at inappropriate times. >> If collision-protect is enabled then it takes precedence over protect-owned. My read of that suggests AT LEAST ONE of the two is recommended, PREFERABLY BOTH, such that collision-protect can better protect the system as a whole under normal circumstances, but can be safely disabled when necessary for individual packages (as in the previously mentioned bug #883561) while still leaving at least some protection in-place during that exception due to protect-owned still being enabled. And that's what I've had in place probably since protect-owned was introduced... So if collision-protect really is negative-recommended now, the above manpage wording implying the opposite /really/ should be changed. =8^O (Never-the-less, the un-recommend is unlikely to change my config choice, but like my -preserve-libs, -* @system and reverse-usrmerge to / instead of /usr, at least now I know my collision-protect doesn't follow current normal recommendations and that I should be prepared to deal with any repercussions of that now deliberate choice as they appear.)