diff --git a/tests/src/helpers.c b/tests/src/helpers.c
index db50296..bf823fe 100644
--- a/tests/src/helpers.c
+++ b/tests/src/helpers.c
@@ -717,4 +717,9 @@
                           line, file);
     }
 }
+
+#if defined(MBEDTLS_TEST_HOOKS)
+void (*mbedtls_test_hook_error_add)(int, int, const char *, int);
+#endif
+
 #endif /* MBEDTLS_TEST_HOOKS */