According to http://bugs.gentoo.org/show_bug.cgi?id=247249 "[accessibility]" should be just dropped from ebuilds. Reproducible: Always Steps to Reproduce: 1.have =dev-cpp/gtkmm-2.12.7 installed 2.unmask media-gfx/rawtherapee 3.emerge rawtherapee Actual Results: emerge: there are no ebuilds built with USE flags to satisfy ">=dev-cpp/gtkmm-2.12[accessibility]". !!! One of the following packages is required to complete your request: - dev-cpp/gtkmm-2.12.7 (Missing IUSE: accessibility) - dev-cpp/gtkmm-2.12.1 (Missing IUSE: accessibility)