[Bug c++/85792] #include <variant> triggers Wctor-dtor-privcay

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85792

Jonathan Wakely <redi at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|diagnostic                  |
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2018-05-18
          Component|libstdc++                   |c++
     Ever confirmed|0                           |1

--- Comment #1 from Jonathan Wakely <redi at gcc dot gnu.org> ---
The warning is bogus, because that type inherits a default constructor from its
base class (also it probably shouldn't give a warning for code in system
headers).

Minimal testcase:

template<typename T> struct A { };

template<typename T> struct B : A<T> {
  using A<T>::A;

  B(const B&) { }
};

It's probably related to constructors in dependent base classes not being seen
at the point the warning is given.