diff --git a/doc/Makefile.local b/doc/Makefile.local
index 16459e35..eec9c228 100644
--- a/doc/Makefile.local
+++ b/doc/Makefile.local
@@ -37,6 +37,10 @@ INFO_INFO_FILES := $(INFO_TEXI_FILES:.texi=.info)
 %.gz: %
 	rm -f $@ && gzip --stdout $^ > $@
 
+ifeq ($(WITH_EMACS),1)
+sphinx-html sphinx-texinfo: docstring.stamp
+endif
+
 sphinx-html:
 	$(SPHINXBUILD) -b html $(ALLSPHINXOPTS) $(DOCBUILDDIR)/html