diff --git a/py/modsys.c b/py/modsys.c
index 8ef66af..d9be7d1 100644
--- a/py/modsys.c
+++ b/py/modsys.c
@@ -120,16 +120,7 @@
 #endif
 };
 
-STATIC const mp_obj_dict_t mp_module_sys_globals = {
-    .base = {&mp_type_dict},
-    .map = {
-        .all_keys_are_qstrs = 1,
-        .table_is_fixed_array = 1,
-        .used = MP_ARRAY_SIZE(mp_module_sys_globals_table),
-        .alloc = MP_ARRAY_SIZE(mp_module_sys_globals_table),
-        .table = (mp_map_elem_t*)mp_module_sys_globals_table,
-    },
-};
+STATIC MP_DEFINE_CONST_DICT(mp_module_sys_globals, mp_module_sys_globals_table);
 
 const mp_obj_module_t mp_module_sys = {
     .base = { &mp_type_module },