[Bug fortran/52102] [OOP] Wrong result with ALLOCATE of CLASS components with array constructor SOURCE-expr

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

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52102

--- Comment #3 from Tobias Burnus <burnus at gcc dot gnu.org> 2012-02-03 13:37:39 UTC ---
Related issue with MOLD=, here one gets with "x = 5" default initialization and

  allocate (two%a(8), mold=t(4))
  print '(*(i2))', two%a(:)%x
the result:
 0 0 0 0 0 0 0 5

That is: only the last element gets the value.

>From the dump:
   two.a._data.offset = -1;
...
     struct t t.2;
     t.2.x = 5;
     D.1886 = t.2;
     __vtab_MAIN___T._copy (&D.1886,
         &(*(struct t[0:] * restrict) two.a._data.data)[two.a._data.offset +
8]);

Note the constant offset of "8", which matches the ubound. Note further that
the _copy construct is *not* in a scalarizing loop but only called once for the
last element.


 * * *

The following looks odd:

gfc_trans_allocate (gfc_code * code)
{
...
      if (code->expr3 && !code->expr3->mold)
        {
...
              /* Do a polymorphic deep copy.  */
...
              actual->next->expr = gfc_copy_expr (al->expr);
              dataref = actual->next->expr->ref;
              if (dataref->u.c.component->as)

The latter makes no sense in this case as the base object is not the class
container. We need to access the last component ref on the ref list.