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-exception 6 // 7 //===----------------------------------------------------------------------===// 8 // UNSUPPORTED: c++03, c++11, c++14, c++17, c++20 9 10 // <mdspan> 11 12 // Test default construction: 13 // 14 // constexpr extents() noexcept = default; 15 // 16 // Remarks: since the standard uses an exposition only array member, dynamic extents 17 // need to be zero intialized! 18 19 #include <mdspan> 20 #include <cassert> 21 #include <array> 22 23 #include "ConvertibleToIntegral.h" 24 #include "CtorTestCombinations.h" 25 #include "test_macros.h" 26 27 struct DefaultCtorTest { 28 template <class E, class AllExtents, class Extents, size_t... Indices> 29 static constexpr void test_construction(AllExtents all_ext, Extents, std::index_sequence<Indices...>) { 30 // This function gets called twice: once with Extents being just the dynamic ones, and once with all the extents specified. 31 // We only test during the all extent case, since then Indices is the correct number. This allows us to reuse the same 32 // testing machinery used in other constructor tests. 33 if constexpr (sizeof...(Indices) == E::rank()) { 34 ASSERT_NOEXCEPT(E{}); 35 // Need to construct new expected values, replacing dynamic values with 0 36 std::array<typename AllExtents::value_type, E::rank()> expected_exts{ 37 ((E::static_extent(Indices) == std::dynamic_extent) 38 ? typename AllExtents::value_type(0) 39 : all_ext[Indices])...}; 40 test_runtime_observers(E{}, expected_exts); 41 } 42 } 43 }; 44 45 int main(int, char**) { 46 test_index_type_combo<DefaultCtorTest>(); 47 static_assert(test_index_type_combo<DefaultCtorTest>()); 48 return 0; 49 } 50