diff --git a/m4/Makefile.am b/m4/Makefile.am
index 80e9201..350b142 100644
--- a/m4/Makefile.am
+++ b/m4/Makefile.am
@@ -32,5 +32,6 @@ EXTRA_DIST = \
 	ax_append_flag.m4	\
 	ax_cflags_warn_all.m4	\
 	ax_c___attribute__.m4	\
+	ax_require_defined.m4	\
 	ax_with_curses.m4	\
 	gnulib-cache.m4
diff --git a/m4/README b/m4/README
index 896d50c..4489a04 100644
--- a/m4/README
+++ b/m4/README
@@ -13,6 +13,7 @@ that project's web site, http://www.gnu.org/software/autoconf-archive/:
     ax_append_flag.m4
     ax_cflags_warn_all.m4
     ax_c___attribute__.m4
+    ax_require_defined.m4
     ax_with_curses.m4
 
 The following macro  was generated by running the  GNU Portability Library