Unexpected compilation problem with g++ -std=c++0x

Question

I have some compilation problems pushing back elements of type T to a vector when compiling with g++ -std=c++0x.

This is a minimal example:

#include <         


        

Answer 1

The standard's definition of copy-assignment operator is (section [class.copy]):

A user-declared copy assignment operator X::operator= is a non-static non-template member function of class X with exactly one parameter of type X, X&, const X&, volatile X& or const volatile X&.

But the X& and volatile X& variants may not be compatible with containers assuming an assignment can be made from an r-value RHS.

NOTE: Passing by value, e.g. X::operator=(X) is a fundamental part of the copy-and-swap idiom.