diff --git a/tests/test4.c b/tests/test4.c
index 7d3d0be..288cec1 100644
--- a/tests/test4.c
+++ b/tests/test4.c
@@ -11,6 +11,7 @@
 #include "json_inttypes.h"
 #include "json_object.h"
 #include "json_tokener.h"
+#include "snprintf_compat.h"
 
 void print_hex(const char *s)
 {