Inappropriate Warning Cannot Be Turned Off

[David Cogen]

Example code fragment, when compiled, produces inappropriate warnings. And
there is no way to disable these warnings.

Compiler: gcc2.95.2
System: SunOS 5.7

Compiled as follows:

  g++ -o test test.cc

The following program:

  #include <iostream.h>
  #include <fstream.h>

  template <class T>
  struct Auto0 {

  public:

    Auto0 () : mValue (0) {}

    operator const T & () const {return mValue;}

    operator T & () {return mValue;}

  private:

    T mValue;

  };

  int main ()
  {
    Auto0 <int> ab;
    cout << "ab = " << ab << " ab+1=" << ab+1 << "\n";
    ++ ab;
    cout << "after incr, ab = " << int(ab) << "\n";
    const Auto0 <int> cd;
    cout << "cd = " << cd << " cd+1=" << cd+1 << "\n";
  }

Produces warnings which are inappropriate:

  test.cc: In function `int main()':
  test.cc:56: warning: choosing `Auto0<int>::operator int &()' over `Auto0<int>::operator const int &() const'
  test.cc:56: warning:   for conversion from `Auto0<int>' to `int'
  test.cc:56: warning:   because conversion sequence for the argument is better
  test.cc:56: warning: choosing `Auto0<int>::operator int &()' over `Auto0<int>::operator const int &() const'
  test.cc:56: warning:   for conversion from `Auto0<int>' to `int'
  test.cc:56: warning:   because conversion sequence for the argument is better
  test.cc:58: warning: choosing `Auto0<int>::operator int &()' over `Auto0<int>::operator const int &() const'
  test.cc:58: warning:   for conversion from `Auto0<int>' to `int'
  test.cc:58: warning:   because conversion sequence for the argument is better

  Compilation finished at Tue Apr 25 13:15:53

-- DavidC