[Bug fortran/44917] New: [OOP] Detect ambiguous specifics in a generic TBP interface

[janus at gcc dot gnu dot org]

The current form of the test case dynamic_dispatch_1.f03 is illegal:


module m
  type :: t1
    integer :: i = 42
    procedure(make_real), pointer :: ptr
  contains
    procedure, pass :: real => make_real
    procedure, pass :: make_integer
    procedure, pass :: prod => i_m_j
    generic, public :: extract => real, make_integer
    generic, public :: base_extract => real, make_integer
  end type t1

  type, extends(t1) :: t2
    integer :: j = 99
  contains
    procedure, pass :: real => make_real2
    procedure, pass :: make_integer_2
    procedure, pass :: prod => i_m_j_2
    generic, public :: extract => real, make_integer_2
  end type t2
contains
  real function make_real (arg)
    class(t1), intent(in) :: arg
    make_real = real (arg%i)
  end function make_real

  real function make_real2 (arg)
    class(t2), intent(in) :: arg
    make_real2 = real (arg%j)
  end function make_real2

  integer function make_integer (arg, arg2)
    class(t1), intent(in) :: arg
    integer :: arg2
    make_integer = arg%i * arg2
  end function make_integer

  integer function make_integer_2 (arg, arg2)
    class(t2), intent(in) :: arg
    integer :: arg2
    make_integer_2 = arg%j * arg2
  end function make_integer_2

  integer function i_m_j (arg)
    class(t1), intent(in) :: arg
        i_m_j = arg%i
  end function i_m_j

  integer function i_m_j_2 (arg)
    class(t2), intent(in) :: arg
        i_m_j_2 = arg%j
  end function i_m_j_2
end module m


It is rejected by the NAG compiler with:

Error: dynamic_dispatch_1.f03, line 58: Ambiguous specific type-bound
procedures MAKE_INTEGER_2 and MAKE_INTEGER for type-bound generic EXTRACT in
type T2

gfortran currently fails to detect that.


-- 
           Summary: [OOP] Detect ambiguous specifics in a generic TBP
                    interface
           Product: gcc
           Version: 4.6.0
            Status: UNCONFIRMED
          Keywords: accepts-invalid
          Severity: normal
          Priority: P3
         Component: fortran
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: janus at gcc dot gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44917