diff --git a/tests/suites/test_suite_x509parse.function b/tests/suites/test_suite_x509parse.function
index 82e4596..dd70790 100644
--- a/tests/suites/test_suite_x509parse.function
+++ b/tests/suites/test_suite_x509parse.function
@@ -7,6 +7,12 @@
 #include "polarssl/oid.h"
 #include "polarssl/base64.h"
 
+#if POLARSSL_X509_MAX_INTERMEDIATE_CA >= 19
+#error "The value of POLARSSL_X509_MAX_INTERMEDIATE_C is larger \
+than the current threshold 19. To test larger values, please \
+adapt the script tests/data_files/dir-max/long.sh."
+#endif
+
 int verify_none( void *data, x509_crt *crt, int certificate_depth, int *flags )
 {
     ((void) data);