[Bug fortran/45961] New: [4.6 Regression] [OOP] Problem with polymorphic type-bound operators

["janus at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=45961

           Summary: [4.6 Regression] [OOP] Problem with polymorphic
                    type-bound operators
           Product: gcc
           Version: 4.6.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: fortran
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: janus@gcc.gnu.org


MODULE DAT_MOD
  TYPE :: DAT
  CONTAINS
    PROCEDURE :: LESS_THAN
    GENERIC :: OPERATOR (.LT.) => LESS_THAN
  END TYPE DAT
CONTAINS
  LOGICAL FUNCTION LESS_THAN(A, B)
    CLASS (DAT), INTENT (IN) :: A, B
    LESS_THAN = .true.
  END FUNCTION LESS_THAN
END MODULE DAT_MOD

PROGRAM TEST
  USE DAT_MOD
  IMPLICIT NONE
  TYPE NODE
    CLASS (DAT), POINTER :: PT
  END TYPE NODE
  TYPE (NODE) :: NDA, NDB
  PRINT *, LST(NDA,NDB)
CONTAINS
  LOGICAL FUNCTION LST(A, B)
    CLASS (NODE), INTENT (IN) :: A, B
    LST = A%PT .LT. B%PT
  END FUNCTION LST
END



$ gfortran-4.6 test.f90
test.f90:21.15:

 PRINT *, LST(NDA,NDB)
              1
Error: Type mismatch in argument 'a' at (1); passed TYPE(node) to CLASS(dat)


This means that for some reason the formal arguments of LST come out
wrongly as CLASS(dat), while they are actually CLASS(node)!?!


Originally reported by Mark Rashid at
http://gcc.gnu.org/ml/fortran/2010-10/msg00104.html.