QA needs to moan on you again. $ emerge -1v @preserved-rebuild These are the packages that would be merged, in order: Calculating dependencies... done! [ebuild R ] dev-libs/volume_key-0.3.9::gentoo USE="-test" PYTHON_SINGLE_TARGET="python3_5 -python3_4 -python3_6" PYTHON_TARGETS="python3_4 python3_5 python3_6" 0 KiB [ebuild U ] sys-libs/libblockdev-2.15-r1::gentoo [2.15::gentoo] USE="cryptsetup%* -bcache -dmraid -doc -kbd -lvm -test (-crypt%*)" PYTHON_SINGLE_TARGET="python3_5 -python3_4 -python3_6" PYTHON_TARGETS="python3_4 python3_5 python3_6" 0 KiB Total: 2 packages (1 upgrade, 1 reinstall), Size of downloads: 0 KiB !!! Multiple package instances within a single package slot have been pulled !!! into the dependency graph, resulting in a slot conflict: sys-libs/libblockdev:0 (sys-libs/libblockdev-2.15-r1:0/0::gentoo, ebuild scheduled for merge) pulled in by (no parents that aren't satisfied by other packages in this slot) (sys-libs/libblockdev-2.15-1:0/0::gentoo, installed) pulled in by >=sys-libs/libblockdev-2.14[crypt] required by (sys-fs/udisks-2.7.5-1:2/2::gentoo, installed) ^^^^^