libstdc++-v3/testsuite/20_util/function/cons/lwg2774.cc

   1 // { dg-do run { target c++11 } }
   2 // { dg-require-effective-target hosted }
   3
   4 #include <functional>
   5 #include <testsuite_hooks.h>
   6
   7 struct Funk
   8 {
   9   Funk() = default;
  10   Funk(const Funk&) { ++copies; }
  11   Funk(Funk&&) { ++moves; }
  12
  13   void operator()() const { }
  14
  15   static int copies;
  16   static int moves;
  17 };
  18
  19 int Funk::copies = 0;
  20 int Funk::moves = 0;
  21
  22 int main()
  23 {
  24   Funk e;
  25   // LWG 2774 means there should be no move here:
  26   std::function<void()> fc(e);
  27   VERIFY(Funk::copies == 1);
  28   VERIFY(Funk::moves == 0);
  29   // And only one move here:
  30   std::function<void()> fm(std::move(e));
  31   VERIFY(Funk::copies == 1);
  32   VERIFY(Funk::moves == 1);
  33 }