Tests don't pass on Fedora 28 (with FOP backend)
$ GTKDOC_TRACE=DEBUG make check
...
FAIL: annotations.sh
$ cat ./tests/annotations/docs/gtkdoc-mkpdf.log
gtkdoc-mkpdf --uninstalled --path=/home/lkundrak/src/gtk-doc/tests/annotations/docs tester tester-docs.xml
2018-07-09 13:30:23,287:mkpdf.py:run:45:INFO:options: {'verbose': False, 'path': ['/home/lkundrak/src/gtk-doc/tests/annotations/docs'], 'imgdir': [], 'uninstalled': True, 'args': ['tester', 'tester-docs.xml']}
2018-07-09 13:30:23,287:mkpdf.py:run_xsltproc:36:INFO:running "/usr/bin/xsltproc --path /home/lkundrak/src/gtk-doc/tests/annotations/docs --nonet --xinclude --stringparam gtkdoc.bookname tester --stringparam gtkdoc.version 1.28.1 --stringparam chunk.quietly 1 --stringparam chunker.output.quiet 1 tester tester-docs.xml -o tester.fo /home/lkundrak/src/gtk-doc/gtk-doc-fo.xsl tester-docs.xml"
$ cat ./tests/annotations/docs/profile.txt
warning: failed to load external entity "tester"
cannot parse tester
$