A follow up for anyone else seeing the same problems with dbus, hal and avahi starting up xfce4.
Finally isolated the problem to a build error in the packages using pkg_comp - it doesn’t happen with builds done in a typical pbulk build environment. It appears that when pkg_comp bootstraps its pbulk environment it sets the ABI option to match the host, in my case an amd64 system. The packages build ok, but they then have the errors I was seeing when they execute. Overriding the ABI parameter in the extra.mk.conf file used by pkg_conf fixes the problem. Also, with the ABI parameter set as it is in the default setup for pkg_comp causes it to build a non-functional version of pkgin as well. When pkgin is built this way it emits some obscure SQL errors trying to access its database. I’ve written up a HOW-TO on getting pkg_comp set up so that it properly builds packages that match the ones on the server as well as ones built in a pbulk build environment. I’ll send it in as soon as I finish tracking down a couple of other things like trying to isolate the funky mouse movements in xfce4 seen in the 2018Q4 and -current pkgsrc archives.
