[Bug c++/52901] New: invalid rvalue reference

[dieter.lucking at googlemail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52901

             Bug #: 52901
           Summary: invalid rvalue reference
    Classification: Unclassified
           Product: gcc
           Version: 4.6.1
            Status: UNCONFIRMED
          Severity: major
          Priority: P3
         Component: c++
        AssignedTo: unassig...@gcc.gnu.org
        ReportedBy: dieter.luck...@googlemail.com


Created attachment 27111
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=27111
code

A different result - just reordering the cout output.

#include <iostream>
using namespace std;

struct X {
        int value;
        X() {
                cout << "default construction" << std::endl;
                value = 0;
        }
        X(const X& other) {
                cout << "copy construction" << std::endl;
                value = 1;
        }
        X(X&& other) {
                cout << "move construction" << std::endl;
                value = 2;
        }

        X& operator = (const X& other) {
                cout << "assignment" << std::endl;
                value = 3;
                return *this;
        }
};

X&& f() {
        X x;
        return std::move(x);
}

int main() {
        cout << "Hello References [1]" << std::endl;
        X   x0 = f();
        cout << "x0: " << x0.value << std::endl;
        X&& x1 = f();
        cout << "No copy construction or assignment expected" << std::endl;
        cout << "x1: " << x1.value << std::endl;

        cout << "Hello References [2]" << std::endl;
        X   y0 = f();
        cout << "y0: " << y0.value << std::endl;
        X&& y1 = f();
        cout << "y1: " << y1.value << std::endl;
        cout << "No copy construction or assignment expected" << std::endl;

        return 0;
 }

// Seems g++ 4.6.1 is buggy:
// Hello References [1]
// default construction
// move construction
// x0: 2
// default construction
// No copy construction or assignment expected
// x1: 6295648
// Hello References [2]
// default construction
// move construction
// y0: 2
// default construction
// y1: 0
// No copy construction or assignment expected