[Bug fortran/61337] New: Wrong indexing and runtime crash with unlimited polymorphic array.

["vladimir.fuka at gmail dot com" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61337

            Bug ID: 61337
           Summary: Wrong indexing and runtime crash with unlimited
                    polymorphic array.
           Product: gcc
           Version: 4.9.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: fortran
          Assignee: unassigned at gcc dot gnu.org
          Reporter: vladimir.fuka at gmail dot com

module array_list

  type container
    class(*), allocatable :: items(:)
  end type


contains

  subroutine add_item(a, e)
    type(container),allocatable,intent(inout) :: a(:)
    class(*),intent(in) :: e(:)
    type(container),allocatable :: tmp(:)

      if (.not.allocated(a)) then
        allocate(a(1))
        allocate(a(1)%items(size(e)), source = e)
      else
        call move_alloc(a,tmp)
        allocate(a(size(tmp)+1))
        a(1:size(tmp)) = tmp
        allocate(a(size(tmp)+1)%items(size(e)), source = e)
      end if
   end subroutine

end module



  use array_list

  type(container), allocatable :: a_list(:)

  call add_item(a_list, [1, 2])

  call print(a_list(1))

contains

  subroutine print(c)
    type(container), intent(in) :: c

    if (allocated(c%items)) then
      select type (x=>c%items)
        type is (integer)
          print *, x
      end select
    end if
  end subroutine

end




> gfortran-4.9 alist-bug.f90 -fcheck=all -g -fbacktrace

> ./a.out 
           2           0


Expected:  1   2



With 

  call add_item(a_list, [1, 2])
  call add_item(a_list, [1, 2])

  do i = 1, size(a_list)
    call print(a_list(i))
  end do


it crashes SIGSEGVs on line:
  allocate(a(size(tmp)+1)%items(size(e)), source = e)


Tested and works on Solaris Studio 12.4.

> sunf90 alist-bug.f90 
> ./a.out 
 1 2
 1 2