ceph/src/boost/libs/variant/test/recursive_wrapper_move_test.cpp

   1 // Copyright (c) 2017
   2 // Mikhail Maximov
   3 //
   4 // Distributed under the Boost Software License, Version 1.0. (See
   5 // accompanying file LICENSE_1_0.txt or copy at
   6 // http://www.boost.org/LICENSE_1_0.txt)
   7
   8 #include "boost/config.hpp"
   9 #include "boost/test/minimal.hpp"
  10
  11 #ifdef __cpp_inheriting_constructors
  12 // Test is based on reported issue:
  13 // https://svn.boost.org/trac/boost/ticket/12680
  14 // GCC 6 crashed, trying to determine is boost::recursive_wrapper<Node>
  15 // is_noexcept_move_constructible
  16
  17 #include <string>
  18 #include <iterator>
  19
  20 #include <boost/variant.hpp>
  21 #include <boost/array.hpp>
  22
  23 struct Leaf { };
  24 struct Node;
  25
  26 typedef boost::variant<Leaf, boost::recursive_wrapper<Node>> TreeBase;
  27
  28 struct Tree : TreeBase {
  29   using TreeBase::TreeBase;
  30
  31   template <typename Iter>
  32   static Tree Create(Iter /*first*/, Iter /*last*/) { return Leaf{}; }
  33 };
  34
  35 struct Node {
  36   Tree left, right;
  37 };
  38
  39
  40 // Test from https://svn.boost.org/trac/boost/ticket/7120
  41 template<class Node>
  42 struct node1_type;
  43
  44 struct var_type;
  45
  46 using var_base = boost::variant<int,
  47   boost::recursive_wrapper<node1_type<var_type>>
  48 >;
  49
  50 template<class Node>
  51 struct node1_type {
  52   boost::array<Node, 1> children;
  53 };
  54
  55 struct var_type : var_base {
  56   using var_base::var_base;
  57 };
  58
  59 void run() {
  60   std::string input{"abracadabra"};
  61   const Tree root = Tree::Create(input.begin(), input.end());
  62   (void)root; // prevents unused variable warning
  63
  64   var_type v1 = 1;
  65   (void)v1;
  66 }
  67
  68 #else // #!ifdef __cpp_inheriting_constructors
  69 // if compiler does not support inheriting constructors - does nothing
  70 void run() {}
  71 #endif
  72
  73 int test_main(int , char* [])
  74 {
  75    run();
  76    return 0;
  77 }
  78