55 lines · cpp
1//===----------------------------------------------------------------------===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8 9// UNSUPPORTED: c++03, c++1110 11// Make sure that we don't blow up the template instantiation recursion depth12// for tuples of size <= 512.13 14#include <tuple>15#include <cassert>16#include <utility>17 18#include "test_macros.h"19 20template <std::size_t... I>21constexpr void CreateTuple(std::index_sequence<I...>) {22 using LargeTuple = std::tuple<std::integral_constant<std::size_t, I>...>;23 using TargetTuple = std::tuple<decltype(I)...>;24 LargeTuple tuple(std::integral_constant<std::size_t, I>{}...);25 assert(std::get<0>(tuple).value == 0);26 assert(std::get<sizeof...(I)-1>(tuple).value == sizeof...(I)-1);27 28 TargetTuple t1 = tuple; // converting copy constructor from &29 TargetTuple t2 = static_cast<LargeTuple const&>(tuple); // converting copy constructor from const&30 TargetTuple t3 = std::move(tuple); // converting rvalue constructor31 TargetTuple t4 = static_cast<LargeTuple const&&>(tuple); // converting const rvalue constructor32 TargetTuple t5; // default constructor33 (void)t1; (void)t2; (void)t3; (void)t4; (void)t5;34 35#if TEST_STD_VER >= 2036 t1 = tuple; // converting assignment from &37 t1 = static_cast<LargeTuple const&>(tuple); // converting assignment from const&38 t1 = std::move(tuple); // converting assignment from &&39 t1 = static_cast<LargeTuple const&&>(tuple); // converting assignment from const&&40 swap(t1, t2); // swap41#endif42 // t1 == tuple; // comparison does not work yet (we blow the constexpr stack)43}44 45constexpr bool test() {46 CreateTuple(std::make_index_sequence<512>{});47 return true;48}49 50int main(int, char**) {51 test();52 static_assert(test(), "");53 return 0;54}55