diff --git a/src/util.h b/src/util.h
index 0b7832fb..6315198a 100644
--- a/src/util.h
+++ b/src/util.h
@@ -25,6 +25,7 @@
 
 #include <stdint.h>
 #include <unistd.h>
+#include <ell/cleanup.h>
 
 #define ___PASTE(a, b) a ## b
 #define __PASTE(a, b) ___PASTE(a, b)
@@ -124,4 +125,6 @@ bool scan_freq_set_isempty(const struct scan_freq_set *set);
 uint32_t *scan_freq_set_to_fixed_array(const struct scan_freq_set *set,
 					size_t *len_out);
 
+DEFINE_CLEANUP_FUNC(scan_freq_set_free);
+
 #endif /* __UTIL_H */