diff -up gnuplot-5.2.4/docs/Makefile.am.doc gnuplot-5.2.4/docs/Makefile.am
--- gnuplot-5.2.4/docs/Makefile.am.doc	2017-12-22 18:32:48.000000000 +0100
+++ gnuplot-5.2.4/docs/Makefile.am	2018-08-08 14:00:40.014932164 +0200
@@ -322,7 +322,7 @@ ${ELCS}: gnuplot-eldoc.el
 # that only appears to work with a non-generated texi file for input.
 
 gnuplot.info: gnuplot.texi
-	$(AM_V_GEN) $(MAKEINFO) -I$(srcdir) $< --no-split --output=$@
+	$(AM_V_GEN) $(MAKEINFO) -I$(srcdir) $< --no-split  --force --output=$@
 
 install-info: gnuplot.info
 	$(AM_V_at) $(top_srcdir)/mkinstalldirs $(DESTDIR)$(infodir)