issue with polymorphism

[Daniel Franke <franke dot daniel at gmail dot com>]

Hi all.

I'm trying to use the polymorphism features of F03 and got stuck with the 
attached testcase - the Fortran and C++ versions should IMO be equivalent, but 
the outcome is not:

$ gfortran hook.f90 && ./a.out 
 hook: a
$ g++  hook.cpp && ./a.out 
hook b

[gcc version 4.6.1, Ubuntu system compiler]

I currently can't update to a 4.7 or latest svn as the build breaks due to 
some multiarch setup issues recently introduced in Ubuntu/Debian.

Until I sorted out my system to compile myself, could somebody be so kind and 
quickly run this through 4.7 and check if this difference still exists and if 
yes, possibly comment if gfortran's behaviour is expected and correct?

Thanks

	Daniel

MODULE m
  TYPE :: a
  CONTAINS
    PROCEDURE :: worker => a_worker
    PROCEDURE :: hook => a_hook
  END TYPE

  TYPE, extends(a) :: b
  CONTAINS
    PROCEDURE :: worker => b_worker
    PROCEDURE :: hook => b_hook
  END TYPE

CONTAINS
  SUBROUTINE a_worker(this)
    CLASS(a), INTENT(in) :: this
    CALL this%hook()
  END SUBROUTINE

  SUBROUTINE a_hook(this)
    CLASS(a), INTENT(in) :: this
    print *, "hook: a"               ! This is wrongly(?) called.
  END SUBROUTINE


  SUBROUTINE b_worker(this)
    CLASS(b), INTENT(in) :: this
    CALL this%a%worker()
  END SUBROUTINE

  SUBROUTINE b_hook(this)
    CLASS(b), INTENT(in) :: this
    print *, "hook: b"
  END SUBROUTINE
END MODULE


  USE m
  TYPE(b) :: obj
  CALL obj%worker()
END

#include <iostream>

class a {
public:
  virtual void worker() {
    hook();
  }

  virtual void hook() {
    std::cout << "hook a" << std::endl;
  }
};

class b : public a {
public:
  void worker() {
    a::worker();
  }

  virtual void hook() {
    std::cout << "hook b" << std::endl;       // This is correctly(?) called.
  }
};

int main() {
  b obj;
  obj.worker();
  return 0;
}