py: Add MICROPY_OBJ_BASE_ALIGNMENT to help with 16-bit ports.
diff --git a/py/mpconfig.h b/py/mpconfig.h
index e8c8fcc..b235d6f 100644
--- a/py/mpconfig.h
+++ b/py/mpconfig.h
@@ -536,6 +536,14 @@
/*****************************************************************************/
/* Miscellaneous settings */
+// All uPy objects in ROM must be aligned on at least a 4 byte boundary
+// so that the small-int/qstr/pointer distinction can be made. For machines
+// that don't do this (eg 16-bit CPU), define the following macro to something
+// like __attribute__((aligned(4))).
+#ifndef MICROPY_OBJ_BASE_ALIGNMENT
+#define MICROPY_OBJ_BASE_ALIGNMENT
+#endif
+
// On embedded platforms, these will typically enable/disable irqs.
#ifndef MICROPY_BEGIN_ATOMIC_SECTION
#define MICROPY_BEGIN_ATOMIC_SECTION() (0)
diff --git a/py/obj.h b/py/obj.h
index 1b1f824..0f61796 100644
--- a/py/obj.h
+++ b/py/obj.h
@@ -46,7 +46,7 @@
struct _mp_obj_type_t;
struct _mp_obj_base_t {
- const struct _mp_obj_type_t *type;
+ const struct _mp_obj_type_t *type MICROPY_OBJ_BASE_ALIGNMENT;
};
typedef struct _mp_obj_base_t mp_obj_base_t;