std::__debug::vector default ctor must not be defaulted

[Jonathan Wakely]

On 29/04/15 08:31 +0200, Stephan Bergmann wrote:
>On 04/28/2015 07:25 PM, Jonathan Wakely wrote:
>>The disadvantage is that you can't compile almost useless code (an
>>empty vector that can never be modified to be non-empty) without
>>adding an explicit initializer.
>
>Turns out there are three places in LibreOffice that use such empty 
>const vectors (to pass into a function that takes a vector const& 
>argument, or to verbosely return an empty vector from a function, 
>[1][2]), but of course no problem to put explicit initializers there.

Yes, as soon as I hit send I thought of some non-useless reasons to do
it, similar to the first of those cases :-)