gtk-doc: breaking changes tree_index.sgml to object_index.sgml
Create a project and add include $(top_srcdir)/gtk-doc.make to your makefile.
Building the documentation results in
warning: failed to load external entity "../xml/tree_index.sgml" ../keybinder-docs.sgml:26: element include: XInclude error : could not load ../xml/tree_index.sgml, and no fallback was found make: *** [Makefile:730: html-build.stamp] Error 6
So depending on the gtk-doc version installed your SGML is supposed to include a different tree_index.sgml, object_index.sgml, how can this be made?