diff --git a/programs/test/cpp_dummy_build.cpp b/programs/test/cpp_dummy_build.cpp
index c65288404..3c9c2786f 100644
--- a/programs/test/cpp_dummy_build.cpp
+++ b/programs/test/cpp_dummy_build.cpp
@@ -97,6 +97,7 @@
 #include "mbedtls/timing.h"
 #include "mbedtls/version.h"
 #include "mbedtls/x509.h"
+#include "mbedtls/x509_internal.h"
 #include "mbedtls/x509_crl.h"
 #include "mbedtls/x509_crt.h"
 #include "mbedtls/x509_csr.h"