| // P2128R6 |
| // { dg-do run } |
| // { dg-options "-std=c++23" } |
| |
| extern "C" void abort (); |
| |
| struct S |
| { |
| constexpr S () : a {} {}; |
| constexpr S (int x, int y, int z) : a {x, y, z} {}; |
| constexpr int &operator[] () { return a[0]; } |
| constexpr int &operator[] (int x) { return a[x]; } |
| constexpr int &operator[] (int x, long y) { return a[x + y * 8]; } |
| int a[64]; |
| }; |
| |
| struct T |
| { |
| operator int () { return 42; }; |
| }; |
| |
| int buf[64]; |
| |
| struct U |
| { |
| operator int * () { return buf; } |
| }; |
| |
| template <int N> |
| void |
| foo () |
| { |
| static_assert (S ()[1] == 0); |
| static_assert (S (1, 2, 42)[2] == 42); |
| static_assert (S ()[3, 4] == 0); |
| static_assert (S (1, 43, 2)[1, 0] == 43); |
| static_assert (S ()[] == 0); |
| static_assert (S (44, 1, 2)[] == 44); |
| S s; |
| for (int i = 0; i < 64; i++) |
| s.a[i] = 64 - i; |
| if (s[] != 64 || s[3] != 61 || s[4, 5] != 20) |
| abort (); |
| s[]++; |
| s[42]++; |
| ++s[3, 2]; |
| if (s.a[0] != 65 || s.a[42] != 23 || s.a[19] != 46) |
| abort (); |
| T t; |
| U u; |
| if (&u[t] != &buf[42]) |
| abort (); |
| if (&t[u] != &buf[42]) |
| abort (); |
| } |
| |
| template <typename V, typename W, typename X> |
| void |
| bar () |
| { |
| static_assert (V ()[1] == 0); |
| static_assert (V (1, 2, 42)[2] == 42); |
| static_assert (V ()[3, 4] == 0); |
| static_assert (V (1, 43, 2)[1, 0] == 43); |
| static_assert (V ()[] == 0); |
| static_assert (V (44, 1, 2)[] == 44); |
| V s; |
| for (int i = 0; i < 64; i++) |
| s.a[i] = 64 - i; |
| if (s[] != 64 || s[3] != 61 || s[4, 5] != 20) |
| abort (); |
| s[]++; |
| s[42]++; |
| ++s[3, 2]; |
| if (s.a[0] != 65 || s.a[42] != 23 || s.a[19] != 46) |
| abort (); |
| W t; |
| X u; |
| if (&u[t] != &buf[42]) |
| abort (); |
| if (&t[u] != &buf[42]) |
| abort (); |
| } |
| |
| int |
| main () |
| { |
| foo <0> (); |
| bar <S, T, U> (); |
| } |