I think the BROKEN flags in ports r473012 were in the window where lxqt-build-tools was updated to 0.5.0 and before x11-toolkits/qtermwidget was updated to 0.9.0. that combination gives the mentioned error. I've succesfully built qtermwidget 0.9.0 on raspberry pi 2.
I further tested 12 current armv7 and aarch64 12 current. x11-toolkits/qtermwidget builds.
A commit references this bug: Author: jsm Date: Sat Jul 7 19:36:04 UTC 2018 New revision: 474130 URL: https://svnweb.freebsd.org/changeset/ports/474130 Log: x11-toolkits/qtermwidget is not broken on armv6 armv7 or aarch64 PR: 229455 Approved by: swills (mentor) Differential Revision: https://reviews.freebsd.org/D16173 Changes: head/x11-toolkits/qtermwidget/Makefile