1 //===----------------------------------------------------------------------===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is dual licensed under the MIT and the University of Illinois Open 6 // Source Licenses. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 10 // <vector> 11 12 // void swap(vector& c) 13 // noexcept(!allocator_type::propagate_on_container_swap::value || 14 // __is_nothrow_swappable<allocator_type>::value); 15 // 16 // In C++17, the standard says that swap shall have: 17 // noexcept(allocator_traits<Allocator>::propagate_on_container_swap::value || 18 // allocator_traits<Allocator>::is_always_equal::value); 19 20 // This tests a conforming extension 21 22 #include <vector> 23 #include <cassert> 24 25 #include "test_allocator.h" 26 27 template <class T> 28 struct some_alloc 29 { 30 typedef T value_type; 31 32 some_alloc() {} 33 some_alloc(const some_alloc&); 34 void deallocate(void*, unsigned) {} 35 36 typedef std::true_type propagate_on_container_swap; 37 }; 38 39 template <class T> 40 struct some_alloc2 41 { 42 typedef T value_type; 43 44 some_alloc2() {} 45 some_alloc2(const some_alloc2&); 46 void deallocate(void*, unsigned) {} 47 48 typedef std::false_type propagate_on_container_swap; 49 typedef std::true_type is_always_equal; 50 }; 51 52 int main() 53 { 54 #if __has_feature(cxx_noexcept) 55 { 56 typedef std::vector<bool> C; 57 C c1, c2; 58 static_assert(noexcept(swap(c1, c2)), ""); 59 } 60 { 61 typedef std::vector<bool, test_allocator<bool>> C; 62 C c1, c2; 63 static_assert(noexcept(swap(c1, c2)), ""); 64 } 65 { 66 typedef std::vector<bool, other_allocator<bool>> C; 67 C c1, c2; 68 static_assert(noexcept(swap(c1, c2)), ""); 69 } 70 { 71 typedef std::vector<bool, some_alloc<bool>> C; 72 C c1, c2; 73 #if TEST_STD_VER >= 14 74 // In c++14, if POCS is set, swapping the allocator is required not to throw 75 static_assert( noexcept(swap(c1, c2)), ""); 76 #else 77 static_assert(!noexcept(swap(c1, c2)), ""); 78 #endif 79 } 80 #if TEST_STD_VER >= 14 81 { 82 typedef std::vector<bool, some_alloc2<bool>> C; 83 C c1, c2; 84 // if the allocators are always equal, then the swap can be noexcept 85 static_assert( noexcept(swap(c1, c2)), ""); 86 } 87 #endif 88 89 #endif 90 } 91
