diff --git a/scripts/dtc/util.h b/scripts/dtc/util.h
index 211d584..23e3296 100644
--- a/scripts/dtc/util.h
+++ b/scripts/dtc/util.h
@@ -70,6 +70,7 @@
 }
 
 extern char *xstrdup(const char *s);
+extern char *xstrndup(const char *s, size_t len);
 
 extern int PRINTF(2, 3) xasprintf(char **strp, const char *fmt, ...);
 extern char *join_path(const char *path, const char *name);