As it happens, my patch just caught one of these cases in my local setup to test builds of all packages from the archive. So, I can now provide sample output:
make[1]: Leaving directory '/build/fwupd-1.1.0' dpkg-genbuildinfo --build=binary dpkg-genchanges --build=binary >../fwupd_1.1.0-7+bpb1_amd64.changes dpkg-genchanges: info: binary-only upload (no source code included) dpkg-source --after-build fwupd-1.1.0 dpkg-buildpackage: info: binary-only upload (no source included) I: copying local configuration I: unmounting /var/cache/pbuildd filesystem I: unmounting dev/pts filesystem I: unmounting dev/shm filesystem I: unmounting proc filesystem I: unmounting sys filesystem W: Cleaning up stray processes from build * system-pbuilder-27742.slice Loaded: loaded Active: active since Sun 2018-08-05 16:49:17 PDT; 2min 23s ago Tasks: 1 Memory: 770.5M CGroup: /system.slice/system-pbuilder.slice/system-pbuilder-27742.slice `-run-rf0fc6f2d6b3b45f7b652a09facf17199.scope `-16261 gpg-agent --homedir /tmp/fwupd-self-test/var/lib/fwupd/gnupg --use-standard-socket --daemon Aug 05 16:49:17 frobozz systemd[1]: Created slice system-pbuilder-27742.slice. I: cleaning the build env I: removing directory /build/chroot-amd64/ and its subdirectories I: Current time: Sun Aug 5 16:51:41 PDT 2018 I: pbuilder-time-stamp: 1533513101 -- Daniel Schepler