diff --git a/libdm/regex/parse_rx.c b/libdm/regex/parse_rx.c
index f9ba65ca1..80e97a4c7 100644
--- a/libdm/regex/parse_rx.c
+++ b/libdm/regex/parse_rx.c
@@ -19,6 +19,7 @@
 #ifdef DEBUG
 #include <ctype.h>
 
+__attribute__ ((__unused__))
 static void _regex_print(struct rx_node *rx, int depth, unsigned show_nodes)
 {
 	int i, numchars;