Oh dear, I apologise. I didn't connect when filing the initial bug report that it was identical to #1112481. Please close this as a duplicate.
Incidentally, the 11.7.0 revision seems to have fixed the problem.
- Bug#1113747: libvirt-daemon: libvirtd core dumps on start... Borden
- Bug#1113747: [Pkg-libvirt-maintainers] Bug#1113747: ... Andrea Bolognani
- Bug#1113747: libvirt-daemon: libvirtd core dumps on ... Borden
- Bug#1113747: [Pkg-libvirt-maintainers] Bug#11137... Andrea Bolognani
