python 3.12 is out for more than a week. python3_12 should be added at PYTHON_COMPAT for systemd. I have tried editing the ebuild and it did not seem to break anything, so the solution seems to be trivial.
The bug has been closed via the following commit(s): https://gitweb.gentoo.org/repo/gentoo.git/commit/?id=366c4051d2fd8f572f37ba993c3fea92bd5c17df commit 366c4051d2fd8f572f37ba993c3fea92bd5c17df Author: Mike Gilbert <floppym@gentoo.org> AuthorDate: 2023-10-12 20:30:54 +0000 Commit: Mike Gilbert <floppym@gentoo.org> CommitDate: 2023-10-12 20:31:20 +0000 sys-apps/systemd-utils: enable py3.12 Closes: https://bugs.gentoo.org/915630 Signed-off-by: Mike Gilbert <floppym@gentoo.org> sys-apps/systemd-utils/systemd-utils-254.5-r1.ebuild | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) https://gitweb.gentoo.org/repo/gentoo.git/commit/?id=3a9db62a816e5c969eaaf861ee89bb81e7182a9e commit 3a9db62a816e5c969eaaf861ee89bb81e7182a9e Author: Mike Gilbert <floppym@gentoo.org> AuthorDate: 2023-10-12 20:30:02 +0000 Commit: Mike Gilbert <floppym@gentoo.org> CommitDate: 2023-10-12 20:31:11 +0000 sys-apps/systemd: enable py3.12 Closes: https://bugs.gentoo.org/915630 Signed-off-by: Mike Gilbert <floppym@gentoo.org> sys-apps/systemd/systemd-254.5.ebuild | 2 +- sys-apps/systemd/systemd-9999.ebuild | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-)