Use the provided way of specifying options Luke
#
# You can set these variables from the command line.
-SPHINXOPTS =
+SPHINXOPTS = -W
SPHINXBUILD = sphinx-build
SPHINXPROJ = BinderHub
SOURCEDIR = .
@@ -17,4 +17,4 @@ help:
# Catch-all target: route all unknown targets to Sphinx using the new
# "make mode" option. $(O) is meant as a shortcut for $(SPHINXOPTS).
%: Makefile
- @$(SPHINXBUILD) -W -M $@ "$(SOURCEDIR)" "$(BUILDDIR)" $(SPHINXOPTS) $(O)
+ @$(SPHINXBUILD) -M $@ "$(SOURCEDIR)" "$(BUILDDIR)" $(SPHINXOPTS) $(O)
