Error when compiling ncurses

I'm trying to compile ncurses 5.9 for an embedded system (using buildroot) and I get this error message:

In file included from ../c++/cursesm.h:39:0,
                 from ../c++/cursesm.cc:35:
../c++/cursesp.h: In member function ‘T* NCursesUserPanel<T>::UserData() const’:
../c++/cursesp.h:256:43: error: no matching function for call to 
‘NCursesUserPanel<T>::get_user() const’
     return reinterpret_cast<T*>(get_user ());

Here's the code in question:

/* We use templates to provide a typesafe mechanism to associate
 * user data with a panel. A NCursesUserPanel<T> is a panel
 * associated with some user data of type T.
 */
template<class T> class NCursesUserPanel : public NCursesPanel
{
public:
  NCursesUserPanel (int nlines,
                    int ncols,
                    int begin_y = 0,
                    int begin_x = 0,
                    const T* p_UserData = STATIC_CAST(T*)(0))
    : NCursesPanel (nlines, ncols, begin_y, begin_x)
  {
      if (p)
        set_user (const_cast<void *>(p_UserData));
  };
  // This creates an user panel of the requested size with associated
  // user data pointed to by p_UserData.

  NCursesUserPanel(const T* p_UserData = STATIC_CAST(T*)(0)) : NCursesPanel()
  {
    if (p)
      set_user(const_cast<void *>(p_UserData));
  };
  // This creates an user panel associated with the ::stdscr and user data
  // pointed to by p_UserData.

  virtual ~NCursesUserPanel() {};

  T* UserData (void) const
  {
    return reinterpret_cast<T*>(get_user ());
  };
  // Retrieve the user data associated with the panel.

  virtual void setUserData (const T* p_UserData)
  {
    if (p)
      set_user (const_cast<void *>(p_UserData));
  }
  // Associate the user panel with the user data pointed to by p_UserData.
};

Line 256 is this one: return reinterpret_cast<T*>(get_user ());

The problem here was due to a compiler update to g++ (Debian 7.2.0-5). New compilers have better error handling, and this old code was written without its benefit. The solution here is to either use a more recent version of ncurses (no-go for my particular situation) or use an older compiler. Since my host system is Debian, I used update-alternatives to switch to g++ 6.4 and the problematic error message went away.

I'm leaving this here because Google gave me no good results for the error message.