using size_t = decltype(sizeof(0));
struct complex_double {
double real;
double imag;
};
template <typename T, size_t ABI, size_t Preferred>
struct check_alignment {
using type = T;
static type value;
static_assert(__alignof__(value) == Preferred, "__alignof__(value) != Preferred");
static_assert(__alignof__(type) == Preferred, "__alignof__(type) != Preferred");
static_assert(alignof(type) == ABI, "alignof(type) != ABI");
};
template struct check_alignment<double, 4, 8>;
template struct check_alignment<long long, 4, 8>;
template struct check_alignment<unsigned long long, 4, 8>;
template struct check_alignment<complex_double, 4, 4>;
struct __attribute__((packed))
packed_struct {
unsigned int a;
} g_packedstruct;
template struct check_alignment<packed_struct, 1, 1>;
static_assert(__alignof__(g_packedstruct.a) == 1, "__alignof__(packed_struct.member) != 1");
template struct check_alignment<double[3], 4, 8>;
enum big_enum { x = 18446744073709551615ULL };
template struct check_alignment<big_enum, 4, 8>;
#define ALIGNED(x) __attribute__((aligned(x)))
typedef ALIGNED(2) struct {
char a[3];
} aligned_before_struct;
static_assert(sizeof(aligned_before_struct) == 3, "");
static_assert(sizeof(aligned_before_struct[1]) == 4, "");
static_assert(sizeof(aligned_before_struct[2]) == 6, "");
static_assert(sizeof(aligned_before_struct[2][1]) == 8, "");
static_assert(sizeof(aligned_before_struct[1][2]) == 6, "");
typedef struct ALIGNED(2) {
char a[3];
} aligned_after_struct;
static_assert(sizeof(aligned_after_struct) == 4, "");
static_assert(sizeof(aligned_after_struct[1]) == 4, "");
static_assert(sizeof(aligned_after_struct[2]) == 8, "");
static_assert(sizeof(aligned_after_struct[2][1]) == 8, "");
static_assert(sizeof(aligned_after_struct[1][2]) == 8, "");