gdm currently hard depends on sys-apps/systemd and the ebuild assumes systemd to be used as init daemon. With sys-auth/elogind there is an alternative to full systemd, so gdm can be run with OpenRC (+ elogind) again. At the very least the ebuild needs to accept sys-auth/elogind as an alternative to systemd and the sys-auth/pambase dependency should be satisfied by either sys-auth/pambase[systemd] or sys-auth/pambase[elogind].
We can't provide such blind modifications before someone actually tests them and confirms that everything works as needed.
The bug has been closed via the following commit(s): https://gitweb.gentoo.org/repo/gentoo.git/commit/?id=003b0f462810dfbeee0edda88243d19983dc3333 commit 003b0f462810dfbeee0edda88243d19983dc3333 Author: Mart Raudsepp <leio@gentoo.org> AuthorDate: 2019-03-19 21:39:51 +0000 Commit: Mart Raudsepp <leio@gentoo.org> CommitDate: 2019-03-19 22:39:20 +0000 gnome-base/gdm: add elogind support Include a patch from 3.32 that removes long gone legacy argument to pam_systemd.so, as to make it uniform with the added elogind support (and not add that legacy arg there too) and be able to reuse the pam-elogind.patch bits for 3.32 without changes, just dropping the argument patch. The elogind support is achieved without configure.ac patches by making use of the standard PKG_CHECK_MODULES builtin AC_ARG_VAR provided variable override support and passing elogind values there as a drop-in replacement. So we don't need an eautoreconf and maintaing an autotools patch until upstream moves to meson. Initial VT is put back to 7 for elogind for the time being until there is more clarity what will happen with startDM.sh and how things interact with agetty out of the box (potential keyboard stealing, etc). Closes: https://bugs.gentoo.org/645348 Package-Manager: Portage-2.3.52, Repoman-2.3.12 Signed-off-by: Mart Raudsepp <leio@gentoo.org> .../gdm/files/3.30.3-pam-drop-legacy-arg.patch | 29 +++ gnome-base/gdm/files/pam-elogind.patch | 24 +++ gnome-base/gdm/gdm-3.30.3-r1.ebuild | 222 +++++++++++++++++++++ gnome-base/gdm/metadata.xml | 1 + 4 files changed, 276 insertions(+)