diff --git a/library/ecp_invasive.h b/library/ecp_invasive.h
index 94867b9..0ea02e2 100644
--- a/library/ecp_invasive.h
+++ b/library/ecp_invasive.h
@@ -40,6 +40,14 @@
     MBEDTLS_ECP_MOD_SCALAR
 } mbedtls_ecp_modulus_type;
 
+#ifndef MBEDTLS_ECP_WITH_MPI_UINT
+
+#define MBEDTLS_ECP_WITH_MPI_UINT
+#undef  MBEDTLS_ECP_WITH_MPI_UINT
+
+#define MBEDTLS_ECP_WITH_MPI_STRUCT
+#endif
+
 #if defined(MBEDTLS_TEST_HOOKS) && defined(MBEDTLS_ECP_LIGHT)
 
 #if defined(MBEDTLS_ECP_MONTGOMERY_ENABLED)