diff --git a/tests/suites/test_suite_pk.function b/tests/suites/test_suite_pk.function
index ac6429bae..2180f5c8e 100644
--- a/tests/suites/test_suite_pk.function
+++ b/tests/suites/test_suite_pk.function
@@ -6,6 +6,7 @@
 #include "mbedtls/rsa.h"
 
 #include <limits.h>
+#include <stdint.h>
 
 static int rnd_std_rand( void *rng_state, unsigned char *output, size_t len );