libstdc++-v3/testsuite/23_containers/vector/modifiers/push_back/89130.cc

   1 // Copyright (C) 2019-2020 Free Software Foundation, Inc.
   2 //
   3 // This file is part of the GNU ISO C++ Library.  This library is free
   4 // software; you can redistribute it and/or modify it under the
   5 // terms of the GNU General Public License as published by the
   6 // Free Software Foundation; either version 3, or (at your option)
   7 // any later version.
   8
   9 // This library is distributed in the hope that it will be useful,
  10 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 // GNU General Public License for more details.
  13
  14 // You should have received a copy of the GNU General Public License along
  15 // with this library; see the file COPYING3.  If not see
  16 // <http://www.gnu.org/licenses/>.
  17
  18 // { dg-do compile { target c++11 } }
  19
  20 #include <vector>
  21
  22 struct T
  23 {
  24   T() { }
  25   T(const T&) { }
  26   T(T&&) = delete;  // this means T is not MoveInsertable into std::vector<T>
  27 };
  28
  29 void f()
  30 {
  31   const T val;
  32   std::vector<T> x;
  33   // push_back(const T&) only requires T is CopyInsertable into std::vector<T>:
  34   x.push_back(val);
  35 }
  36
  37 template<typename U>
  38 struct Alloc
  39 {
  40   using value_type = U;
  41   Alloc() = default;
  42   Alloc(const Alloc&) = default;
  43   template<typename U2>
  44     Alloc(const Alloc<U2>&) { }
  45
  46   U* allocate(unsigned n) { return std::allocator<U>().allocate(n); }
  47   void deallocate(U* p, unsigned n) { std::allocator<U>().deallocate(p, n); }
  48
  49   void construct(Alloc*, U* p, U&& u)
  50   {
  51     // construct from const lvalue instead of rvalue:
  52     ::new(p) U(const_cast<const U&>(u));
  53   }
  54 };
  55
  56 void g()
  57 {
  58   const T val;
  59   std::vector<T, Alloc<T>> x;
  60   // push_back(const T&) only requires T is CopyInsertable into std::vector<T>:
  61   x.push_back(val);
  62 }