c2280 default constructor for std::vector requires copy constructor for elements despite having move constructor

Question

Title says it all, under what circumstances would the default constructor for std::vector require a copy constructor for the elements and not accept only a move constructor? I am explicitly deleting the copy constructor and explicitly defaulting the move constructor using VS2017.

Maybe this: http://stackoverflow.com/questions/8001823/how-to-enforce-move-semantics-when-a-vector-grows — NathanOliver, Apr 21 '17 at 15:55
show a minimal complete compilable example, there may be another error being misreported in this way — Ben Voigt, Apr 21 '17 at 16:11

Corristo · Answer 1 · 2017-04-21T16:18:18.560

Before C++11, std::vector required that the element type is copy-constructible and copy-assignable.

From C++11 onwards the type requirements for the element type of a std::vector have been weakened, and std::vector now only requires the element type to be complete (until C++17) and erasable by the given allocator.

Calling certain member functions however, might impose additional requirements on the element type. The default constructor is not one of them, though.

That means that the element type doesn't need to have a copy-constructor for the vector to be default constructible - in fact you can default construct a std::vector with an element type that is not constructible at all (see here).

c2280 default constructor for std::vector requires copy constructor for elements despite having move constructor

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