diff --git a/tests/suites/test_suite_pkcs7.function b/tests/suites/test_suite_pkcs7.function
index 3c93d0f..3585522 100644
--- a/tests/suites/test_suite_pkcs7.function
+++ b/tests/suites/test_suite_pkcs7.function
@@ -8,6 +8,7 @@
 #include "sys/types.h"
 #include "sys/stat.h"
 #include "mbedtls/rsa.h"
+#include "mbedtls/error.h"
 /* END_HEADER */
 
 /* BEGIN_DEPENDENCIES