The following happened when building the latest cpython tip documentation. I don't think it's a bug in Sphinx, but the error message told me to report it, so this is what I'm doing.
$ make html mkdir -p build/html build/doctrees python tools/sphinx-build.py -b html -d build/doctrees -D latex_paper_size= . build/html Running Sphinx v1.0.7 loading pickled environment... done building [html]: targets for 437 source files that are out of date updating environment: [extensions changed] 434 added, 0 changed, 3 removed reading sources... [100%] whatsnew/index looking for now-outdated files... none found pickling environment... done checking consistency... done preparing documents... done writing output... [ 42%] library/enum Exception occurred: File "/home/nikratio/clones/cpython/Doc/tools/sphinxext/pyspecific.py", line 46, in new_visit_literal_block meta = self.builder.env.metadata[self.builder.current_docname] KeyError: 'library/enum' The full traceback has been saved in /tmp/sphinx-err-kQuGXN.log, if you want to report the issue to the developers. Please also report this if it was a user error, so that a better error message can be provided next time. Either send bugs to the mailing list at <http://groups.google.com/group/sphinx-dev/>, or report them in the tracker at <http://bitbucket.org/birkenfeld/sphinx/issues/>. Thanks! make: *** [build] Error 1