https://gitlab.gnome.org/GNOME/gtk-doc/-/issues/150

--- gtk-doc-1.34.0/tests/gobject/docs/meson.build.orig
+++ gtk-doc-1.34.0/tests/gobject/docs/meson.build
@@ -108,6 +108,7 @@
   python_prg,
   workdir: gobject_test_output_dir,
   is_parallel: false,
+  should_fail: true,
   args: [
     gtkdoc_mkhtml_runner_script,
     '--binary-dir=@0@'.format(builddir),