[Bug c++/97740] [10/11/12/13 Regression] Weird error message about accessing a private member of my own class inside of std::string_view inside of constexpr

["ppalka at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97740

--- Comment #4 from Patrick Palka <ppalka at gcc dot gnu.org> ---
A C++14 version that's more similar to the original testcase using a generic
lambda and dependent initializer:

struct A {
  constexpr const int* get() const { return &m; }
private:
  int m = 42;
} a;

struct B { const int* p; };

template<A* arg>
void f() {
  [] (auto) {
    constexpr B b = {arg->get()};
  }(0);
}

template void f<&a>();