--- doc/interpreter/Makefile.am.orig	2012-01-31 17:47:52.000000000 +0000
+++ doc/interpreter/Makefile.am	2012-01-31 17:49:37.000000000 +0000
@@ -202,6 +202,8 @@
 	$(AWK) -f $(srcdir)/mkcontrib.awk $(srcdir)/contributors.in > $@-t
 	mv $@-t $@
 
+preface.texi: contributors.texi
+
 ../../AUTHORS: preface.texi contributors.texi
 	rm -f AUTHORS
 	-$(MAKEINFO) -D AUTHORSONLY \