Can std :: move () or its explicit equivalent of a local variable resolve elision?

Question

For instance:

Big create()
{
    Big x;
    return std::move(x);
//  return static_cast<typename std::remove_reference<T>::type&&>(t) // why not elide here?
}

Assuming that applying std::move()to return a local variable prohibits movement-semantics, because compilers cannot make any assumptions about the internal functions of functions in general, with regard to cases where these assumptions are not needed, for example, when:

• std::move(x) built-in (possibly always)
• std::move(x) is written as: static_cast<typename std::remove_reference<T>::type&&>(t)

In accordance with the current standard, implementations are allowed to apply NRVO ...

- return , - ( , - (18.3)) ( cv-qualification) , /

, 1), 2) . , std::move() , ?

Answer 1

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Answer 2

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