[Bug fortran/57710] New: [OOP] _vptr not set for allocatable CLASS components

[burnus at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57710

            Bug ID: 57710
           Summary: [OOP] _vptr not set for allocatable CLASS components
           Product: gcc
           Version: 4.9.0
            Status: UNCONFIRMED
          Keywords: ice-on-valid-code, wrong-code
          Severity: normal
          Priority: P3
         Component: fortran
          Assignee: unassigned at gcc dot gnu.org
          Reporter: burnus at gcc dot gnu.org

The following code (minus the IF condition) shows that _vptr is not set for the
allocatable component:
        y.x._data = 0B;
there should be - but isn't - additionally: y.x._vptr = &__vtab_m_T;


Additionally, the test case as is (with IF condition), currently crashes with:

internal compiler error: in gfc_conv_component_ref, at
fortran/trans-expr.c:1654
   if (.not. same_type_as(y%x, z)) call abort ()
 ^
0x632ce2 gfc_conv_component_ref
        ../../gcc/fortran/trans-expr.c:1654
0x63fc89 gfc_conv_variable
        ../../gcc/fortran/trans-expr.c:1921


module m
  type t
  end type t
  type t2
    integer :: ii
    class(t), allocatable :: x
  end type t2
contains
  subroutine fini(x)
     type(t) :: x
  end subroutine fini
end module m

use m
block
  type(t) :: z
  type(t2) :: y
  y%ii = 123
  if (.not. same_type_as(y%x, z)) call abort ()
end block
end