From [12.8] [11] of N3337:
The implicitly-defined copy/move constructor for a non-union class X performs a memberwise copy/move of its bases and members. [ Note: brace-or-equal-initializers of non-static data members are ignored. See also the example in 12.6.2. —end note ] The order of initialization is the same as the order of initialization of bases and members in a user-defined constructor (see 12.6.2). Let x be either the parameter of the constructor or, for the move constructor, an xvalue referring to the parameter. Each base or non-static data member is copied/moved in the manner appropriate to its type:
— if the member is an array, each element is direct-initialized with the corresponding subobject of x;
— if a member m has rvalue reference type T&&, it is direct-initialized with static_cast(x.m);
— otherwise, the base or member is direct-initialized with the corresponding base or member of x.
This is really more of a clarification, but I can't see any mention of reference members in that clause. Since it doesn't mention them, by default it seems to say that they are part of the memberwise move, yet the following would not work;
int x = 5;
int& y = x;
int& z(std::move(y)); //error: invalid initialization of non-const reference of type 'int&' from an rvalue of type 'std::remove_reference<int&>::type {aka int}'
So is it safe to assume that the default move constructor distinguishes that a member is a reference and would simply just do
int& z = y;
with no call to std::move
?
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