1 files changed, 1 insertions, 2 deletions
diff --git a/py/modio.c b/py/modio.c
index e79d59e4e5..3e37231f23 100644
--- a/py/modio.c
+++ b/py/modio.c
@@ -121,8 +121,7 @@ typedef struct _mp_obj_bufwriter_t {
 STATIC mp_obj_t bufwriter_make_new(const mp_obj_type_t *type, size_t n_args, size_t n_kw, const mp_obj_t *args) {
     mp_arg_check_num(n_args, n_kw, 2, 2, false);
     size_t alloc = mp_obj_get_int(args[1]);
-    mp_obj_bufwriter_t *o = m_new_obj_var(mp_obj_bufwriter_t, byte, alloc);
-    o->base.type = type;
+    mp_obj_bufwriter_t *o = mp_obj_malloc_var(mp_obj_bufwriter_t, byte, alloc, type);
     o->stream = args[0];
     o->alloc = alloc;
     o->len = 0;