354 #define flex_array_size(p, member, count)				\  argument
355 	__builtin_choose_expr(__is_constexpr(count),			\
356 		(count) * sizeof(*(p)->member) + __must_be_array((p)->member),	\
357 		size_mul(count, sizeof(*(p)->member) + __must_be_array((p)->member)))
370 #define struct_size(p, member, count)					\  argument
371 	__builtin_choose_expr(__is_constexpr(count),			\
372 		sizeof(*(p)) + flex_array_size(p, member, count),	\
373 		size_add(sizeof(*(p)), flex_array_size(p, member, count)))
388 #define struct_size_t(type, member, count)					\  argument
389 	struct_size((type *)NULL, member, count)
401 #define __DEFINE_FLEX(type, name, member, count, trailer...)			\  argument
402 	_Static_assert(__builtin_constant_p(count),				\
405 		u8 bytes[struct_size_t(type, member, count)];			\
420 #define _DEFINE_FLEX(type, name, member, count, initializer...)			\  argument
421 	__DEFINE_FLEX(type, name, member, count, = { .obj initializer })
436 #define DEFINE_RAW_FLEX(type, name, member, count)	\  argument
437 	__DEFINE_FLEX(type, name, member, count, = { })