diff --git a/docs/Makefile b/docs/Makefile
index 6495e5866..8f13f1aea 100644
--- a/docs/Makefile
+++ b/docs/Makefile
@@ -9,9 +9,9 @@ PAPER         =
 BUILDDIR      = _build
 
 # Internal variables.
-PAPEROPT_a4     = -D latex_paper_size=a4
-PAPEROPT_letter = -D latex_paper_size=letter
-ALLSPHINXOPTS   = -d $(BUILDDIR)/doctrees $(PAPEROPT_$(PAPER)) $(SPHINXOPTS) .
+PAPEROPT_a4     = --define latex_paper_size=a4
+PAPEROPT_letter = --define latex_paper_size=letter
+ALLSPHINXOPTS   = --doctree-dir $(BUILDDIR)/doctrees $(PAPEROPT_$(PAPER)) $(SPHINXOPTS) .
 # the i18n builder cannot share the environment and doctrees with the others
 I18NSPHINXOPTS  = $(PAPEROPT_$(PAPER)) $(SPHINXOPTS) .
 
@@ -51,42 +51,42 @@ install-sphinx:
 .PHONY: html
 html:
 	$(MAKE) install-sphinx
-	$(SPHINXBUILD) -b html -W --keep-going $(ALLSPHINXOPTS) $(BUILDDIR)/html
+	$(SPHINXBUILD) --builder html --fail-on-warning --keep-going $(ALLSPHINXOPTS) $(BUILDDIR)/html
 	@echo
 	@echo "Build finished. The HTML pages are in $(BUILDDIR)/html."
 
 .PHONY: dirhtml
 dirhtml:
 	$(MAKE) install-sphinx
-	$(SPHINXBUILD) -b dirhtml $(ALLSPHINXOPTS) $(BUILDDIR)/dirhtml
+	$(SPHINXBUILD) --builder dirhtml $(ALLSPHINXOPTS) $(BUILDDIR)/dirhtml
 	@echo
 	@echo "Build finished. The HTML pages are in $(BUILDDIR)/dirhtml."
 
 .PHONY: singlehtml
 singlehtml:
 	$(MAKE) install-sphinx
-	$(SPHINXBUILD) -b singlehtml $(ALLSPHINXOPTS) $(BUILDDIR)/singlehtml
+	$(SPHINXBUILD) --builder singlehtml $(ALLSPHINXOPTS) $(BUILDDIR)/singlehtml
 	@echo
 	@echo "Build finished. The HTML page is in $(BUILDDIR)/singlehtml."
 
 .PHONY: pickle
 pickle:
 	$(MAKE) install-sphinx
-	$(SPHINXBUILD) -b pickle $(ALLSPHINXOPTS) $(BUILDDIR)/pickle
+	$(SPHINXBUILD) --builder pickle $(ALLSPHINXOPTS) $(BUILDDIR)/pickle
 	@echo
 	@echo "Build finished; now you can process the pickle files."
 
 .PHONY: json
 json:
 	$(MAKE) install-sphinx
-	$(SPHINXBUILD) -b json $(ALLSPHINXOPTS) $(BUILDDIR)/json
+	$(SPHINXBUILD) --builder json $(ALLSPHINXOPTS) $(BUILDDIR)/json
 	@echo
 	@echo "Build finished; now you can process the JSON files."
 
 .PHONY: htmlhelp
 htmlhelp:
 	$(MAKE) install-sphinx
-	$(SPHINXBUILD) -b htmlhelp $(ALLSPHINXOPTS) $(BUILDDIR)/htmlhelp
+	$(SPHINXBUILD) --builder htmlhelp $(ALLSPHINXOPTS) $(BUILDDIR)/htmlhelp
 	@echo
 	@echo "Build finished; now you can run HTML Help Workshop with the" \
 	      ".hhp project file in $(BUILDDIR)/htmlhelp."
@@ -94,7 +94,7 @@ htmlhelp:
 .PHONY: qthelp
 qthelp:
 	$(MAKE) install-sphinx
-	$(SPHINXBUILD) -b qthelp $(ALLSPHINXOPTS) $(BUILDDIR)/qthelp
+	$(SPHINXBUILD) --builder qthelp $(ALLSPHINXOPTS) $(BUILDDIR)/qthelp
 	@echo
 	@echo "Build finished; now you can run "qcollectiongenerator" with the" \
 	      ".qhcp project file in $(BUILDDIR)/qthelp, like this:"
@@ -105,7 +105,7 @@ qthelp:
 .PHONY: devhelp
 devhelp:
 	$(MAKE) install-sphinx
-	$(SPHINXBUILD) -b devhelp $(ALLSPHINXOPTS) $(BUILDDIR)/devhelp
+	$(SPHINXBUILD) --builder devhelp $(ALLSPHINXOPTS) $(BUILDDIR)/devhelp
 	@echo
 	@echo "Build finished."
 	@echo "To view the help file:"
@@ -116,14 +116,14 @@ devhelp:
 .PHONY: epub
 epub:
 	$(MAKE) install-sphinx
-	$(SPHINXBUILD) -b epub $(ALLSPHINXOPTS) $(BUILDDIR)/epub
+	$(SPHINXBUILD) --builder epub $(ALLSPHINXOPTS) $(BUILDDIR)/epub
 	@echo
 	@echo "Build finished. The epub file is in $(BUILDDIR)/epub."
 
 .PHONY: latex
 latex:
 	$(MAKE) install-sphinx
-	$(SPHINXBUILD) -b latex $(ALLSPHINXOPTS) $(BUILDDIR)/latex
+	$(SPHINXBUILD) --builder latex $(ALLSPHINXOPTS) $(BUILDDIR)/latex
 	@echo
 	@echo "Build finished; the LaTeX files are in $(BUILDDIR)/latex."
 	@echo "Run \`make' in that directory to run these through (pdf)latex" \
@@ -132,7 +132,7 @@ latex:
 .PHONY: latexpdf
 latexpdf:
 	$(MAKE) install-sphinx
-	$(SPHINXBUILD) -b latex $(ALLSPHINXOPTS) $(BUILDDIR)/latex
+	$(SPHINXBUILD) --builder latex $(ALLSPHINXOPTS) $(BUILDDIR)/latex
 	@echo "Running LaTeX files through pdflatex..."
 	$(MAKE) -C $(BUILDDIR)/latex all-pdf
 	@echo "pdflatex finished; the PDF files are in $(BUILDDIR)/latex."
@@ -140,21 +140,21 @@ latexpdf:
 .PHONY: text
 text:
 	$(MAKE) install-sphinx
-	$(SPHINXBUILD) -b text $(ALLSPHINXOPTS) $(BUILDDIR)/text
+	$(SPHINXBUILD) --builder text $(ALLSPHINXOPTS) $(BUILDDIR)/text
 	@echo
 	@echo "Build finished. The text files are in $(BUILDDIR)/text."
 
 .PHONY: man
 man:
 	$(MAKE) install-sphinx
-	$(SPHINXBUILD) -b man $(ALLSPHINXOPTS) $(BUILDDIR)/man
+	$(SPHINXBUILD) --builder man $(ALLSPHINXOPTS) $(BUILDDIR)/man
 	@echo
 	@echo "Build finished. The manual pages are in $(BUILDDIR)/man."
 
 .PHONY: texinfo
 texinfo:
 	$(MAKE) install-sphinx
-	$(SPHINXBUILD) -b texinfo $(ALLSPHINXOPTS) $(BUILDDIR)/texinfo
+	$(SPHINXBUILD) --builder texinfo $(ALLSPHINXOPTS) $(BUILDDIR)/texinfo
 	@echo
 	@echo "Build finished. The Texinfo files are in $(BUILDDIR)/texinfo."
 	@echo "Run \`make' in that directory to run these through makeinfo" \
@@ -163,7 +163,7 @@ texinfo:
 .PHONY: info
 info:
 	$(MAKE) install-sphinx
-	$(SPHINXBUILD) -b texinfo $(ALLSPHINXOPTS) $(BUILDDIR)/texinfo
+	$(SPHINXBUILD) --builder texinfo $(ALLSPHINXOPTS) $(BUILDDIR)/texinfo
 	@echo "Running Texinfo files through makeinfo..."
 	make -C $(BUILDDIR)/texinfo info
 	@echo "makeinfo finished; the Info files are in $(BUILDDIR)/texinfo."
@@ -171,21 +171,21 @@ info:
 .PHONY: gettext
 gettext:
 	$(MAKE) install-sphinx
-	$(SPHINXBUILD) -b gettext $(I18NSPHINXOPTS) $(BUILDDIR)/locale
+	$(SPHINXBUILD) --builder gettext $(I18NSPHINXOPTS) $(BUILDDIR)/locale
 	@echo
 	@echo "Build finished. The message catalogs are in $(BUILDDIR)/locale."
 
 .PHONY: changes
 changes:
 	$(MAKE) install-sphinx
-	$(SPHINXBUILD) -b changes $(ALLSPHINXOPTS) $(BUILDDIR)/changes
+	$(SPHINXBUILD) --builder changes $(ALLSPHINXOPTS) $(BUILDDIR)/changes
 	@echo
 	@echo "The overview file is in $(BUILDDIR)/changes."
 
 .PHONY: linkcheck
 linkcheck:
 	$(MAKE) install-sphinx
-	$(SPHINXBUILD) -b linkcheck $(ALLSPHINXOPTS) $(BUILDDIR)/linkcheck -j auto
+	$(SPHINXBUILD) --builder linkcheck $(ALLSPHINXOPTS) $(BUILDDIR)/linkcheck -j auto
 	@echo
 	@echo "Link check complete; look for any errors in the above output " \
 	      "or in $(BUILDDIR)/linkcheck/output.txt."
@@ -193,7 +193,7 @@ linkcheck:
 .PHONY: doctest
 doctest:
 	$(MAKE) install-sphinx
-	$(SPHINXBUILD) -b doctest $(ALLSPHINXOPTS) $(BUILDDIR)/doctest
+	$(SPHINXBUILD) --builder doctest $(ALLSPHINXOPTS) $(BUILDDIR)/doctest
 	@echo "Testing of doctests in the sources finished, look at the " \
 	      "results in $(BUILDDIR)/doctest/output.txt."