问题描述
在中，我们了解到RVO不能应用于 p .first 。
In this question we've learnt that RVO cannot be applied to an expression like p.first.
在注释中，还建议RVO通常不适用于 r 之后声明如 auto& r = p.first 。不太清楚标准是否强制这种行为。
In comments it was also suggested that RVO is generally not applied to an expression like r after a declaration like auto& r = p.first. It is less clear whether the standard mandates this behaviour.
在下面的代码中，是也被称为 o 的对象的 r a 名称在 return 语句中形成表达式时允许使用RVO？
In the following code, is r a name of the object also known as o, to the extent that RVO is permissible when it forms the expression in a return statement?
int o = 42;
int& r = o;
推荐答案
解决了与对象不同的引用没有实际名称的事实的值。该问题已由解决，它扩展了变量的概念以包含引用，从而给出它们的名称。
现在[basic] / 6读（所有重点由我）：
CWG #633 addressed the fact that references, unlike objects, didn't have actual names. It was resolved by N2993, which extended the notion of a variable to encompass references, thereby giving them names.
Now [basic]/6 reads (all emphasis by me):
引用表示变量 - 引用 - 不是引用引用的对象。虽然引用通常被解释为对象/函数的其他名称，但在标准术语中，定义是明文错误的。
The name of a reference denotes that variable - the reference - not the object that the reference refers to. Although references are commonly explained as being "other names of objects/functions", in standard terms that definition is plain wrong.
由于上述文件直到2009年才被采纳，并且您已将：一可以认为该文件是C ++ 03的回顾性校正。但是，在C ++ 03中，严格来说，引用不是一个实体（这是通过），因此其声明中的标识符从不被视为名称（参见[basic] / 4，名称必须表示标签或实体） - 因此复制elision不适用，再次。
Since the above paper was not adopted until 2009, and you tagged c++03: One can consider the paper as a retrospective correction of C++03. However, in C++03, strictly speaking, a reference is not an entity (this was rectified by CWG #485) and therefore the identifier in its declaration is never treated as a name (see [basic]/4, a name must denote a label or entity) - hence copy elision doesn't apply, again.
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