diff --git a/src/logging.c b/src/logging.c
index 5f22df71..f6361553 100644
--- a/src/logging.c
+++ b/src/logging.c
@@ -20,6 +20,7 @@ Contributors:
 #include <stdarg.h>
 #include <stdio.h>
 #include <string.h>
+#include <inttypes.h>
 #ifndef WIN32
 #include <syslog.h>
 #endif
diff --git a/src/sys_tree.c b/src/sys_tree.c
index 5350fa56..c44565a4 100644
--- a/src/sys_tree.c
+++ b/src/sys_tree.c
@@ -23,6 +23,7 @@ Contributors:
 #include <math.h>
 #include <stdio.h>
 #include <limits.h>
+#include <inttypes.h>
 
 #include "mosquitto_broker_internal.h"
 #include "memory_mosq.h"