[Bug c++/80858] When trying to copy std::unordered_map illegally, error message doesn't tell what's wrong

[sgunderson at bigfoot dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80858

--- Comment #4 from sgunderson at bigfoot dot com ---
I think this should work as reduction:

struct Empty {
};

template<class T>
struct A
{
        A &operator=(const A&) 
        {
                T t(3);
                return *this;
        }       
};

class B
{       
        A<Empty> a;
};

int main(void)
{
        B b1, b2;
        b1 = b2;
}


The error is attributed to the line with “class B”, without ever mentioning the
“b1 = b2;” line.