| 1 | #include <cstdio> |
| 2 | #include <string> |
| 3 | #include <variant> |
| 4 | #include <vector> |
| 5 | |
| 6 | struct S { |
| 7 | S() = default; |
| 8 | S(S &&) { throw 42; } |
| 9 | S &operator=(S &&) = default; |
| 10 | }; |
| 11 | |
| 12 | int main() { |
| 13 | std::variant<int, double, char> v1; |
| 14 | std::variant<int, double, char> &v1_ref = v1; |
| 15 | |
| 16 | using V1_typedef = std::variant<int, double, char>; |
| 17 | V1_typedef v1_typedef; |
| 18 | V1_typedef &v1_typedef_ref = v1_typedef; |
| 19 | |
| 20 | std::variant<int, double, char> v2; |
| 21 | std::variant<int, double, char> v3; |
| 22 | std::variant<std::variant<int, double, char>> v_v1; |
| 23 | std::variant<int, char, S> v_valueless = 5; |
| 24 | // The next variant has 300 types, meaning the type index does not fit in |
| 25 | // a byte and must be `unsigned short` instead of `unsigned char` when |
| 26 | // using the unstable libc++ ABI. With stable libc++ ABI, the type index |
| 27 | // is always just `unsigned int`. |
| 28 | std::variant< |
| 29 | int, int, int, int, int, int, int, int, int, int, int, int, int, int, int, |
| 30 | int, int, int, int, int, int, int, int, int, int, int, int, int, int, int, |
| 31 | int, int, int, int, int, int, int, int, int, int, int, int, int, int, int, |
| 32 | int, int, int, int, int, int, int, int, int, int, int, int, int, int, int, |
| 33 | int, int, int, int, int, int, int, int, int, int, int, int, int, int, int, |
| 34 | int, int, int, int, int, int, int, int, int, int, int, int, int, int, int, |
| 35 | int, int, int, int, int, int, int, int, int, int, int, int, int, int, int, |
| 36 | int, int, int, int, int, int, int, int, int, int, int, int, int, int, int, |
| 37 | int, int, int, int, int, int, int, int, int, int, int, int, int, int, int, |
| 38 | int, int, int, int, int, int, int, int, int, int, int, int, int, int, int, |
| 39 | int, int, int, int, int, int, int, int, int, int, int, int, int, int, int, |
| 40 | int, int, int, int, int, int, int, int, int, int, int, int, int, int, int, |
| 41 | int, int, int, int, int, int, int, int, int, int, int, int, int, int, int, |
| 42 | int, int, int, int, int, int, int, int, int, int, int, int, int, int, int, |
| 43 | int, int, int, int, int, int, int, int, int, int, int, int, int, int, int, |
| 44 | int, int, int, int, int, int, int, int, int, int, int, int, int, int, int, |
| 45 | int, int, int, int, int, int, int, int, int, int, int, int, int, int, int, |
| 46 | int, int, int, int, int, int, int, int, int, int, int, int, int, int, int, |
| 47 | int, int, int, int, int, int, int, int, int, int, int, int, int, int, int, |
| 48 | int, int, int, int, int, int, int, int, int, int, int, int, int, int, int, |
| 49 | S> |
| 50 | v_300_types_valueless; |
| 51 | |
| 52 | v_valueless = 5; |
| 53 | v_300_types_valueless.emplace<0>(10); |
| 54 | |
| 55 | v1 = 12; // v contains int |
| 56 | v1_typedef = v1; |
| 57 | v_v1 = v1; |
| 58 | int i = std::get<int>(v1); |
| 59 | printf(format: "%d\n" , i); // break here |
| 60 | |
| 61 | v2 = 2.0; |
| 62 | double d = std::get<double>(v2); |
| 63 | printf(format: "%f\n" , d); |
| 64 | |
| 65 | v3 = 'A'; |
| 66 | char c = std::get<char>(v3); |
| 67 | printf(format: "%d\n" , c); |
| 68 | |
| 69 | // Checking v1 above and here to make sure we done maintain the incorrect |
| 70 | // state when we change its value. |
| 71 | v1 = 2.0; |
| 72 | d = std::get<double>(v1); |
| 73 | printf(format: "%f\n" , d); // break here |
| 74 | |
| 75 | try { |
| 76 | // Exception in type-changing move-assignment is guaranteed to put |
| 77 | // std::variant into a valueless state. |
| 78 | v_valueless = S(); |
| 79 | } catch (...) { |
| 80 | } |
| 81 | |
| 82 | printf(format: "%d\n" , v_valueless.valueless_by_exception()); |
| 83 | |
| 84 | try { |
| 85 | // Exception in move-assignment is guaranteed to put std::variant into a |
| 86 | // valueless state. |
| 87 | v_300_types_valueless = S(); |
| 88 | } catch (...) { |
| 89 | } |
| 90 | |
| 91 | printf("%d\n" , v_300_types_valueless.valueless_by_exception()); |
| 92 | |
| 93 | return 0; // break here |
| 94 | } |
| 95 | |