[Bug fortran/56500] New: [OOP] "IMPLICIT CLASS(...)" wrongly rejected

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

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56500

             Bug #: 56500
           Summary: [OOP] "IMPLICIT CLASS(...)" wrongly rejected
    Classification: Unclassified
           Product: gcc
           Version: 4.8.0
            Status: UNCONFIRMED
          Keywords: rejects-valid
          Severity: normal
          Priority: P3
         Component: fortran
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: burnus@gcc.gnu.org
                CC: janus@gcc.gnu.org


Found at http://mailman.j3-fortran.org/pipermail/j3/2013-March/006167.html

"IMPLICIT CLASS(...) (...)" does not properly work with gfortran.


R560  implicit-stmt  is  IMPLICIT implicit-spec-list
                     or  IMPLICIT NONE
R561  implicit-spec  is  declaration-type-spec ( letter-spec-list )
R403 declaration-type-spec  is  intrinsic-type-spec
                            or  TYPE ( intrinsic-type-spec )
                            or  TYPE ( derived-type-spec )
                            or  CLASS ( derived-type-spec )
                            or  CLASS ( * )


Example by Reinhold Bader:

module mod_upimp
  type :: foo
     integer :: i
  end type
end module
program upimp
  use mod_upimp
  implicit class(foo) (a-b)
  implicit class(*) (c)
  allocatable :: aaf, caf
  allocate(aaf, source=foo(2))
  allocate(caf, source=foo(3))
  select type (aaf)
  type is (foo)
    write(*,*) aaf
  end select
  select type (caf)
  type is (foo)
    write(*,*) caf
  end select
end program