diff --git a/src/engine/engine_array_safety.h b/src/engine/engine_array_safety.h
index b5d31159..ce3fe4ff 100644
--- a/src/engine/engine_array_safety.h
+++ b/src/engine/engine_array_safety.h
@@ -15,6 +15,10 @@
 #ifndef MUJOCO_SRC_ENGINE_ENGINE_ARRAY_SAFETY_H_
 #define MUJOCO_SRC_ENGINE_ENGINE_ARRAY_SAFETY_H_
 
+#ifdef __cplusplus
+#error This file should not be used from C++ code.
+#endif
+
 #include <stdio.h>
 #include <string.h>
 
diff --git a/test/xml/xml_native_reader_test.cc b/test/xml/xml_native_reader_test.cc
index 7d939bfb..04ea596c 100644
--- a/test/xml/xml_native_reader_test.cc
+++ b/test/xml/xml_native_reader_test.cc
@@ -22,7 +22,7 @@
 #include <gtest/gtest.h>
 #include <mujoco/mjmodel.h>
 #include <mujoco/mujoco.h>
-#include "src/engine/engine_array_safety.h"
+#include "src/cc/array_safety.h"
 #include "src/engine/engine_util_errmem.h"
 #include "test/fixture.h"
 
@@ -147,7 +147,7 @@ TEST_F(UserDataTest, RaiseNanWarning) {
   static char warning[1024];
   warning[0] = '\0';
   mju_user_warning = [](const char* msg) {
-    mjSTRNCPY(warning, msg);
+    util::strcpy_arr(warning, msg);
   };
   mjModel* model = LoadModelFromString(xml, error.data(), error.size());
 #if defined(_WIN32) || defined(__CYGWIN__)