diff --git a/shared-bindings/audiocore/RawSample.c b/shared-bindings/audiocore/RawSample.c
index 04ddf282b6..265515c3e1 100644
--- a/shared-bindings/audiocore/RawSample.c
+++ b/shared-bindings/audiocore/RawSample.c
@@ -72,7 +72,7 @@
 STATIC mp_obj_t audioio_rawsample_make_new(const mp_obj_type_t *type, size_t n_args, size_t n_kw, const mp_obj_t *all_args) {
     enum { ARG_buffer, ARG_channel_count, ARG_sample_rate };
     static const mp_arg_t allowed_args[] = {
-        { MP_QSTR_buffer, MP_ARG_OBJ | MP_ARG_REQUIRED },
+        { MP_QSTR_buffer, MP_ARG_OBJ | MP_ARG_REQUIRED, {.u_obj = MP_OBJ_NULL } },
         { MP_QSTR_channel_count, MP_ARG_INT | MP_ARG_KW_ONLY, {.u_int = 1 } },
         { MP_QSTR_sample_rate, MP_ARG_INT | MP_ARG_KW_ONLY, {.u_int = 8000} },
     };
diff --git a/shared-bindings/audiomixer/Mixer.c b/shared-bindings/audiomixer/Mixer.c
index 04d80caf78..99b9e1f5bf 100644
--- a/shared-bindings/audiomixer/Mixer.c
+++ b/shared-bindings/audiomixer/Mixer.c
@@ -201,7 +201,7 @@ MP_PROPERTY_GETTER(audiomixer_mixer_voice_obj,
 STATIC mp_obj_t audiomixer_mixer_obj_play(size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) {
     enum { ARG_sample, ARG_voice, ARG_loop };
     static const mp_arg_t allowed_args[] = {
-        { MP_QSTR_sample,    MP_ARG_OBJ | MP_ARG_REQUIRED },
+        { MP_QSTR_sample,    MP_ARG_OBJ | MP_ARG_REQUIRED, {} },
         { MP_QSTR_voice,     MP_ARG_INT | MP_ARG_KW_ONLY, {.u_int = 0} },
         { MP_QSTR_loop,      MP_ARG_BOOL | MP_ARG_KW_ONLY, {.u_bool = false} },
     };
diff --git a/shared-bindings/audiomixer/MixerVoice.c b/shared-bindings/audiomixer/MixerVoice.c
index f2003abd75..aaa5aedb58 100644
--- a/shared-bindings/audiomixer/MixerVoice.c
+++ b/shared-bindings/audiomixer/MixerVoice.c
@@ -64,7 +64,7 @@ STATIC mp_obj_t audiomixer_mixervoice_make_new(const mp_obj_type_t *type, size_t
 STATIC mp_obj_t audiomixer_mixervoice_obj_play(size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) {
     enum { ARG_sample, ARG_loop };
     static const mp_arg_t allowed_args[] = {
-        { MP_QSTR_sample,    MP_ARG_OBJ | MP_ARG_REQUIRED },
+        { MP_QSTR_sample,    MP_ARG_OBJ | MP_ARG_REQUIRED, {} },
         { MP_QSTR_loop,      MP_ARG_BOOL | MP_ARG_KW_ONLY, {.u_bool = false} },
     };
     audiomixer_mixervoice_obj_t *self = MP_OBJ_TO_PTR(pos_args[0]);
@@ -105,7 +105,7 @@ MP_DEFINE_CONST_FUN_OBJ_1(audiomixer_mixervoice_get_level_obj, audiomixer_mixerv
 STATIC mp_obj_t audiomixer_mixervoice_obj_set_level(size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) {
     enum { ARG_level };
     static const mp_arg_t allowed_args[] = {
-        { MP_QSTR_level,     MP_ARG_OBJ | MP_ARG_REQUIRED },
+        { MP_QSTR_level,     MP_ARG_OBJ | MP_ARG_REQUIRED, {} },
     };
     audiomixer_mixervoice_obj_t *self = MP_OBJ_TO_PTR(pos_args[0]);
     mp_arg_val_t args[MP_ARRAY_SIZE(allowed_args)];
diff --git a/shared-bindings/bitmaptools/__init__.c b/shared-bindings/bitmaptools/__init__.c
index a6fc785a68..eef80a654a 100644
--- a/shared-bindings/bitmaptools/__init__.c
+++ b/shared-bindings/bitmaptools/__init__.c
@@ -970,11 +970,11 @@ STATIC mp_obj_t bitmaptools_obj_draw_circle(size_t n_args, const mp_obj_t *pos_a
     enum {ARG_dest_bitmap, ARG_x, ARG_y, ARG_radius, ARG_value};
 
     static const mp_arg_t allowed_args[] = {
-        {MP_QSTR_dest_bitmap, MP_ARG_REQUIRED | MP_ARG_OBJ},
-        {MP_QSTR_x, MP_ARG_REQUIRED | MP_ARG_INT},
-        {MP_QSTR_y, MP_ARG_REQUIRED | MP_ARG_INT},
-        {MP_QSTR_radius, MP_ARG_REQUIRED | MP_ARG_INT},
-        {MP_QSTR_value, MP_ARG_REQUIRED | MP_ARG_INT},
+        {MP_QSTR_dest_bitmap, MP_ARG_REQUIRED | MP_ARG_OBJ, {}},
+        {MP_QSTR_x, MP_ARG_REQUIRED | MP_ARG_INT, {}},
+        {MP_QSTR_y, MP_ARG_REQUIRED | MP_ARG_INT, {}},
+        {MP_QSTR_radius, MP_ARG_REQUIRED | MP_ARG_INT, {}},
+        {MP_QSTR_value, MP_ARG_REQUIRED | MP_ARG_INT, {}},
     };
     mp_arg_val_t args[MP_ARRAY_SIZE(allowed_args)];
     mp_arg_parse_all(n_args, pos_args, kw_args, MP_ARRAY_SIZE(allowed_args), allowed_args, args);
diff --git a/shared-bindings/struct/__init__.c b/shared-bindings/struct/__init__.c
index a1257c67c3..7434e85cf9 100644
--- a/shared-bindings/struct/__init__.c
+++ b/shared-bindings/struct/__init__.c
@@ -132,8 +132,8 @@ MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(struct_unpack_obj, 2, 3, struct_unpack);
 STATIC mp_obj_t struct_unpack_from(size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) {
     enum { ARG_format, ARG_buffer, ARG_offset };
     static const mp_arg_t allowed_args[] = {
-        { MP_QSTR_format, MP_ARG_REQUIRED | MP_ARG_OBJ },
-        { MP_QSTR_buffer, MP_ARG_REQUIRED | MP_ARG_OBJ },
+        { MP_QSTR_format, MP_ARG_REQUIRED | MP_ARG_OBJ, {} },
+        { MP_QSTR_buffer, MP_ARG_REQUIRED | MP_ARG_OBJ, {} },
         { MP_QSTR_offset, MP_ARG_INT, {.u_int = 0} },
     };
 
diff --git a/shared-bindings/synthio/MidiTrack.c b/shared-bindings/synthio/MidiTrack.c
index 1c385c0229..33bdc9bc40 100644
--- a/shared-bindings/synthio/MidiTrack.c
+++ b/shared-bindings/synthio/MidiTrack.c
@@ -75,8 +75,8 @@
 STATIC mp_obj_t synthio_miditrack_make_new(const mp_obj_type_t *type, size_t n_args, size_t n_kw, const mp_obj_t *all_args) {
     enum { ARG_buffer, ARG_tempo, ARG_sample_rate, ARG_waveform, ARG_envelope };
     static const mp_arg_t allowed_args[] = {
-        { MP_QSTR_buffer, MP_ARG_OBJ | MP_ARG_REQUIRED },
-        { MP_QSTR_tempo, MP_ARG_INT | MP_ARG_REQUIRED },
+        { MP_QSTR_buffer, MP_ARG_OBJ | MP_ARG_REQUIRED, {} },
+        { MP_QSTR_tempo, MP_ARG_INT | MP_ARG_REQUIRED, {} },
         { MP_QSTR_sample_rate, MP_ARG_INT | MP_ARG_KW_ONLY, {.u_int = 11025} },
         { MP_QSTR_waveform, MP_ARG_OBJ | MP_ARG_KW_ONLY, {.u_obj = mp_const_none } },
         { MP_QSTR_envelope, MP_ARG_OBJ | MP_ARG_KW_ONLY, {.u_obj = mp_const_none } },
diff --git a/shared-bindings/synthio/__init__.c b/shared-bindings/synthio/__init__.c
index 6f0fbd2782..4907870a5c 100644
--- a/shared-bindings/synthio/__init__.c
+++ b/shared-bindings/synthio/__init__.c
@@ -233,7 +233,7 @@ const mp_obj_namedtuple_type_t synthio_envelope_type_obj = {
 STATIC mp_obj_t synthio_from_file(size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) {
     enum { ARG_file, ARG_sample_rate, ARG_waveform, ARG_envelope };
     static const mp_arg_t allowed_args[] = {
-        { MP_QSTR_file, MP_ARG_OBJ | MP_ARG_REQUIRED },
+        { MP_QSTR_file, MP_ARG_OBJ | MP_ARG_REQUIRED, {} },
         { MP_QSTR_sample_rate, MP_ARG_INT | MP_ARG_KW_ONLY, {.u_int = 11025} },
         { MP_QSTR_waveform, MP_ARG_OBJ | MP_ARG_KW_ONLY, {.u_obj = mp_const_none } },
         { MP_QSTR_envelope, MP_ARG_OBJ | MP_ARG_KW_ONLY, {.u_obj = mp_const_none } },