diff --git a/libaf/af_channels.c b/libaf/af_channels.c
index 0d915f3716..3e9482deda 100644
--- a/libaf/af_channels.c
+++ b/libaf/af_channels.c
@@ -6,6 +6,7 @@
 #include <stdlib.h>
 #include <string.h>
 #include <unistd.h>
+#include <inttypes.h>
 
 #include "../config.h"
 #include "../mp_msg.h"