[Bug fortran/57079] New: [Fortran-dev] version/type/attribute fields not set with CLASS components

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

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57079

             Bug #: 57079
           Summary: [Fortran-dev] version/type/attribute fields not set
                    with CLASS components
    Classification: Unclassified
           Product: gcc
           Version: fortran-dev
            Status: UNCONFIRMED
          Keywords: wrong-code
          Severity: normal
          Priority: P3
         Component: fortran
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: burnus@gcc.gnu.org
                CC: pault@gcc.gnu.org
            Blocks: 56818


The following test case shows that the version etc. field is not properly set
for:

subroutine foo()
  type t2
  end type t2
  type t
    integer, allocatable :: x(:)
    class(t2), allocatable :: y(:)
    integer :: z = 55
  end type t
  type(t), allocatable :: x!(:)
   allocate(x)
end

I wrote that it is a CLASS problem, but it might also affect other allocatable
components if there is a default initializer.


The problem is that the following code is generated, i.e. the initialization is
overridden. The additional issue is that there is a missed optimization
(setting the same value multiple times) - which should be avoided if possible.
There might be also other cases, where the fields aren't properly set.


        x = (struct t *) __builtin_malloc (128);
      ...
      x->x.base_addr = 0B;
      x->x.version = 1;
      ...
      x->y._data.base_addr = 0B;
      x->y._data.version = 1;
      ...
      {
        struct t t.0;

        if (x != 0B) goto L.1;
        x = (struct t *) __builtin_calloc (1, 128);
        L.1:;
        t.0.x.base_addr = 0B;
        t.0.y._data.base_addr = 0B;
        t.0.y._vptr = (struct __vtype_foo_T2 * {ref-all}) &__vtab_foo_T2;
        t.0.z = 55;
        *x = t.0;