[Bug fortran/45900] New: [OOP] Polymorphic method not called

["ortp21 at gmail dot com" <gcc-bugzilla at gcc dot gnu dot org>]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=45900

           Summary: [OOP] Polymorphic method not called
           Product: gcc
           Version: 4.6.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: fortran
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: ortp21@gmail.com


The following example code provides an incorrect result using gfortran 4.6.0
20100925. I believe the code is valid and I have tested the same code with the
Intel Fortran compiler (ifort) 11.1 on Linux and the results returned are
correct. See the below example:

types.f90
---------------------------------------------------------
module A
implicit none
    type :: aType
    contains
        procedure :: callback
    end type aType
    contains
        subroutine callback( callback_ )
            implicit none
            class(aType) :: callback_

            print *, "Error: aType method called."
        end subroutine callback

        subroutine solver( callback_ )
            implicit none
            class(aType) :: callback_

            call callback_%callback()
        end subroutine solver
end module A

module B
use A, only: aType
implicit none
    type, extends(aType) :: bType
        integer :: i
    contains
        procedure :: callback
    end type bType
    contains
        subroutine callback( callback_ )
            implicit none
            class(bType) :: callback_

            print *, "Made it."
        end subroutine callback
end module B

program main
use A
use B
implicit none
    type(bType) :: bTypeInstance
    integer :: iflag

    bTypeInstance%i = 4

    call bTypeInstance%callback()
    call solver( bTypeInstance )
end program main
---------------------------------------------------------

The result produced running this code are found to be:
$ gfortran -o t types.f90
$ ./t
 Error: aType method called.
 Made it.

While ifort correctly produces the result:
 Made it.
 Made it.

A workaround is to do change "use A" in the main to:

use A, only: solver


Using built-in specs.
COLLECT_GCC=gfortran
Target: x86_64-apple-darwin10.4.0
Configured with: ../gcc-4.6-20100925/configure --prefix=~$HOME/gcc-trunk
--enable-languages=fortran --enable-checking=release --disable-bootstrap
Thread model: posix
gcc version 4.6.0 20100925 (experimental) (GCC)