[Bug c++/58589] diagnostics: missing proper file:line on C++ compilation error

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=58589

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|WAITING                     |NEW

--- Comment #4 from Jonathan Wakely <redi at gcc dot gnu.org> ---
(In reply to Jan Kratochvil from comment #0)
> #include <unordered_map>
> #include <memory>
> class X {
> public:
>   int a,&b; /* the reference disables default copy constructor */

What has the copy constructor got to do with anything?

std::unique_ptr<X> never tries to copy an X

Reduced:

template<class T>
struct impl
{
  T t;

  impl& operator=(const impl& i) { t = i.t; return *this; }
};

template<class T>
struct unordered_map
{
  impl<T> m_impl;
};

struct unique_ptr {
  unique_ptr& operator=(const unique_ptr&) = delete;
};

struct Y {
  unordered_map<unique_ptr> x;
};

int main() {
  Y a;
  a = a;
}

j.cc: In instantiation of ‘impl<T>& impl<T>::operator=(const impl<T>&) [with T
= unique_ptr]’:
j.cc:10:8:   required from here
j.cc:6:38: error: use of deleted function ‘unique_ptr&
unique_ptr::operator=(const unique_ptr&)’
   impl& operator=(const impl& i) { t = i.t; return *this; }
                                    ~~^~~~~
j.cc:16:15: note: declared here
   unique_ptr& operator=(const unique_ptr&) = delete;
               ^~~~~~~~

There's nothing showing the location of the "a = a" expression that requires
the deleted Y::operator=(const Y&).