// PR c++/89780 // { dg-do compile { target c++11 } } // { dg-options "-Wpessimizing-move -Wredundant-move" } // Define std::move. namespace std { template struct remove_reference { typedef _Tp type; }; template struct remove_reference<_Tp&> { typedef _Tp type; }; template struct remove_reference<_Tp&&> { typedef _Tp type; }; template constexpr typename std::remove_reference<_Tp>::type&& move(_Tp&& __t) noexcept { return static_cast::type&&>(__t); } } struct Dest { Dest() = default; Dest(Dest&&); Dest(const Dest&); }; struct Source : Dest {}; template Dest withMove() { T x; return std::move(x); } template Dest withMove(); template Dest withMove(); template Dest bar () { return std::move(T()); // { dg-warning "moving a temporary object prevents copy elision" } } template Dest bar(); template Dest bar(); template Dest baz (T x) { return std::move(x); } void call_baz () { Dest d; Source s; baz (d); baz (s); } template Dest foo () { Dest d; return std::move(d); // { dg-warning "moving a local object in a return statement prevents copy elision" } } template Dest foo(); template Dest qux () { return std::move(Dest()); // { dg-warning "moving a temporary object prevents copy elision" } } template Dest qux(); template Dest qui (Dest x) { return std::move(x); // { dg-warning "redundant move in return statement" } } void call_qui () { Dest d; qui (d); }