Last added USE mask in profiles/base/package.use.mask violates the ebuild spec by using inline comments which are explicitely forbidden (at least in all non-masked portage versions): from portage(5): package.use.mask and package.use.stable.mask Per-package USE flag masks. […] Format: - comments begin with # (no inline comments) - one DEPEND atom per line with space-delimited USE flags Reproducible: Always Steps to Reproduce: 1. sync portage 2. break portage Actual Results: cave@1370357462: [WARNING e.profile.failure] In thread ID '18456': ... In program cave sync: ... When triggering hook 'sync_all_post': ... When performing hook 'sync_all_post' for repository 'gentoo': ... When updating news at location '/var/db/paludis/repositories/gentoo/metadata/news' for repository 'gentoo': ... When handling news entry '/var/db/paludis/repositories/gentoo/metadata/news/2011-02-19-ia64-java-removal': ... When checking Display-If-Keyword headers: ... When loading profiles '/etc/paludis/profile' for repository 'gentoo': ... When using directory '/etc/paludis/profile': ... When adding profile directory '/etc/paludis/profile: ... When handling parent file for profile directory '/etc/paludis/profile: ... When adding profile directory '/var/db/paludis/repositories/gentoo/profiles/default/linux/amd64: ... When handling parent file for profile directory '/var/db/paludis/repositories/gentoo/profiles/default/linux/amd64/13.0: ... When adding profile directory '/var/db/paludis/repositories/gentoo/profiles/default/linux/amd64: ... When handling parent file for profile directory '/var/db/paludis/repositories/gentoo/profiles/default/linux/amd64: ... When adding profile directory '/var/db/paludis/repositories/gentoo/profiles/base: ... When loading specised use file '/var/db/paludis/repositories/gentoo/profiles/base/package.use.mask: ... Ignoring token '#' due to exception 'Name '#' is not a valid choice name with prefix' (paludis::ChoiceNameWithPrefixError) cave@1370357462: [WARNING e.profile.failure] (same context) Ignoring token '#' due to exception 'Name '#' is not a valid choice name with prefix' (paludis::ChoiceNameWithPrefixError) cave@1370357462: [WARNING e.profile.failure] (same context) Ignoring token '#' due to exception 'Name '#' is not a valid choice name with prefix' (paludis::ChoiceNameWithPrefixError) cave@1370357462: [WARNING e.profile.failure] (same context) Ignoring token '#' due to exception 'Name '#' is not a valid choice name with prefix' (paludis::ChoiceNameWithPrefixError) USE mask not applied. Expected Results: Silence. A masked USE flag.
That's not how it works. However, the PMS states that one-item-per-line should be used where blank lines and lines starting with a # are removed; since the syntax for an item (in this case, a package ATOM) does not permit the use of the # character, it is invalid.
http://sources.gentoo.org/viewvc.cgi/gentoo-x86/profiles/base/package.use.mask?r1=1.472&r2=1.473