72 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// <vector>10 11// Make sure we don't miscompile vector operations for types that shouldn't be considered12// trivially relocatable.13 14#include <vector>15#include <cassert>16#include <cstddef>17#include <type_traits>18#include <utility>19 20#include "test_macros.h"21 22struct Tracker {23 std::size_t move_constructs = 0;24};25 26struct [[clang::trivial_abi]] Inner {27 TEST_CONSTEXPR_CXX20 explicit Inner(Tracker* tracker) : tracker_(tracker) {}28 TEST_CONSTEXPR_CXX20 Inner(const Inner& rhs) : tracker_(rhs.tracker_) { tracker_->move_constructs += 1; }29 TEST_CONSTEXPR_CXX20 Inner(Inner&& rhs) : tracker_(rhs.tracker_) { tracker_->move_constructs += 1; }30 Tracker* tracker_;31};32 33// Even though this type contains a trivial_abi type, it is not trivially move-constructible,34// so we should not attempt to optimize its move construction + destroy using trivial relocation.35struct NotTriviallyMovable {36 TEST_CONSTEXPR_CXX20 explicit NotTriviallyMovable(Tracker* tracker) : inner_(tracker) {}37 TEST_CONSTEXPR_CXX20 NotTriviallyMovable(NotTriviallyMovable&& other) : inner_(std::move(other.inner_)) {}38 Inner inner_;39};40static_assert(!std::is_trivially_copyable<NotTriviallyMovable>::value, "");41LIBCPP_STATIC_ASSERT(!std::__libcpp_is_trivially_relocatable<NotTriviallyMovable>::value, "");42 43TEST_CONSTEXPR_CXX20 bool tests() {44 Tracker track;45 std::vector<NotTriviallyMovable> v;46 47 // Fill the vector at its capacity, such that any subsequent push_back would require growing.48 v.reserve(5);49 std::size_t const capacity = v.capacity(); // could technically be more than 550 while (v.size() < v.capacity()) {51 v.emplace_back(&track);52 }53 assert(track.move_constructs == 0);54 assert(v.capacity() == capacity);55 assert(v.size() == capacity);56 57 // Force a reallocation of the buffer + relocalization of the elements.58 // All the existing elements of the vector should be move-constructed to their new location.59 v.emplace_back(&track);60 assert(track.move_constructs == capacity);61 62 return true;63}64 65int main(int, char**) {66 tests();67#if TEST_STD_VER >= 2068 static_assert(tests());69#endif70 return 0;71}72