sizeof and __offsetof

• sizeof(Type) gives the size of a type in bytes.
• sizeof(value) gives the size of the value's V type, including when its storage moves to the heap. Value expressions such as sizeof(values[0]) and sizeof(record.field) use the visible local or parameter, including when it shadows a module constant.
• __offsetof(Struct, field_name) gives the offset in bytes of a struct field.