Bug#886340: FTBFS: Could not connect to display :0 during doc build

[Scott Kitterman]

Package: src:ovito
Version: 2.9.0+dfsg1-5
Severity: serious
Justification: fails to build from source (but built successfully in the past)

Dear Maintainer,

Here is the end of the build log:

[ 99%] Built target Ovito
make -f CMakeFiles/scripting_documentation.dir/build.make CMakeFiles/scripting_documentation.dir/depend
make[3]: Entering directory '/home/ovito-2.9.0+dfsg1/obj-x86_64-linux-gnu'
cd /home/ovito-2.9.0+dfsg1/obj-x86_64-linux-gnu && /usr/bin/cmake -E cmake_depends "Unix Makefiles" /home/ovito-2.9.0+dfsg1 /home/ovito-2.9.0+dfsg1 /home/ovito-2.9.0+dfsg1/obj-x86_64-linux-gnu /home/ovito-2.9.0+dfsg1/obj-x86_64-linux-gnu /home/ovito-2.9.0+dfsg1/obj-x86_64-linux-gnu/CMakeFiles/scripting_documentation.dir/DependInfo.cmake --color=
Scanning dependencies of target scripting_documentation
make[3]: Leaving directory '/home/ovito-2.9.0+dfsg1/obj-x86_64-linux-gnu'
make -f CMakeFiles/scripting_documentation.dir/build.make CMakeFiles/scripting_documentation.dir/build
make[3]: Entering directory '/home/ovito-2.9.0+dfsg1/obj-x86_64-linux-gnu'
[100%] Generating scripting documentation
cd /home/ovito-2.9.0+dfsg1/doc/python && /home/ovito-2.9.0+dfsg1/obj-x86_64-linux-gnu/bin/ovitos /usr/bin/sphinx-build -b html -a -E -D version=2.9 -D release=2.9.0 . /home/ovito-2.9.0+dfsg1/obj-x86_64-linux-gnu/share/ovito/doc/manual/html/python/
QStandardPaths: XDG_RUNTIME_DIR not set, defaulting to '/tmp/runtime-root'
No protocol specified
qt.qpa.screen: QXcbConnection: Could not connect to display :0
Could not connect to any X display.
CMakeFiles/scripting_documentation.dir/build.make:60: recipe for target 'CMakeFiles/scripting_documentation' failed
make[3]: *** [CMakeFiles/scripting_documentation] Error 1
make[3]: Leaving directory '/home/ovito-2.9.0+dfsg1/obj-x86_64-linux-gnu'
CMakeFiles/Makefile2:71: recipe for target 'CMakeFiles/scripting_documentation.dir/all' failed
make[2]: *** [CMakeFiles/scripting_documentation.dir/all] Error 2
make[2]: Leaving directory '/home/ovito-2.9.0+dfsg1/obj-x86_64-linux-gnu'
Makefile:165: recipe for target 'all' failed
make[1]: *** [all] Error 2
make[1]: Leaving directory '/home/ovito-2.9.0+dfsg1/obj-x86_64-linux-gnu'
dh_auto_build: cd obj-x86_64-linux-gnu && make -j4 returned exit code 2
debian/rules:5: recipe for target 'build-arch' failed
make: *** [build-arch] Error 2
dpkg-buildpackage: error: debian/rules build-arch subprocess returned exit status 2

Note that this is after applying the fix for qscintilla2 library detection in
#885644 (which seems very unlrelated - I can reproduce this with the old
qscintilla2 as well).

This is the last package blocking completion of the current qscintilla2
transition, so your near-term attention to this would be appreciated.

The failures are all from builds inside a pbuilder chroot, so I suppose there
is some chance this is a pbuilder/sbuild thing, but I don't plan on heaving
a source only upload at the buildds to see what happens.

Scott K