[Bug fortran/42545] New: TBP: Wrongly reject inherite TBP with types with private components

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

Reported by Reinhold Bader.

The error occurs for inherited type-bound procedures where the extending type
has "PRIVATE" for the components and the TBP procedure is accessed using the
syntax
   <type> % <extended type> % <TBP>
The error message is as follows:

mr_shorter.f90:23.14:

  call  obj%tt%set()
              1
Error: All components of 'ttt' are PRIVATE in structure constructor at (1)

The error is wrong for two reasons:
a) There is no structure constructure visible at all
b) This TBP is public as there is no PRIVATE statement below the CONTAINS in
the type declaration.

See "4.5.4 Type-bound procedures" and esp. last two normative paragraphs of
this section. And see "4.5.6.1 Inheritance" (all refs are F2003):

"An extended type has a scalar, nonpointer, nonallocatable, parent component
with the type and type parameters of the parent type. The name of this
component is the parent type name. It has the accessibility of the parent
type."


! -----------------------------------------
module mo
  implicit none
  type :: tt
    private
    integer :: i = 1
  contains
    procedure :: set
  end type
  type, extends(tt) :: ttt
    private ! <<<<<<<
    real :: x = 2.0
  end type
contains
  subroutine set(this)
    class(tt) :: this
    this%i = -1
  end subroutine
end module
program pr
  use mo
  implicit none
  type(ttt) :: obj
  call  obj%tt%set()
end program
! -------------------

Variants to check:

type tt
 ...
contains
  PRIVATE
! (and optionally "set" explicitly marked as public)

-- and/or --

type, extends(tt) :: t
 ...
contains
  PRIVATE


-- 
           Summary: TBP: Wrongly reject inherite TBP with types with private
                    components
           Product: gcc
           Version: 4.5.0
            Status: UNCONFIRMED
          Keywords: rejects-valid
          Severity: normal
          Priority: P3
         Component: fortran
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: burnus at gcc dot gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42545