+ifeq ($(WITH_EMACS),1)
+$(DOCBUILDDIR)/.roff.stamp sphinx-html sphinx-texinfo: docstring.stamp
+endif
+
+# Sequentialize the calls to sphinx-build to avoid races with
+# reading/writing cached state. This uses GNU make specific
+# "order-only" prerequisites.
+
+sphinx-html: | $(DOCBUILDDIR)/.roff.stamp
+sphinx-texinfo: | sphinx-html
+sphinx-info: | sphinx-texinfo
+