[Bug middle-end/83758] ICE building gccgo on powerpc64le --with-cpu=power8

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83758

--- Comment #3 from seurer at gcc dot gnu.org ---
The code below is were the assertion is failing (the line after // WDS test). 
I was experimenting a bit and commented out the assertion so I could see what
it was guarding and ... nothing happened, at least I don't think so.  The
compiler built and there weren't any unusual failures in the go test cases. 
Could it be the assertion isn't really needed?

static inline rtx
vt_expand_var_loc_chain (variable *var, bitmap regs, void *data,
                         bool *pendrecp)
{
  struct expand_loc_callback_data *elcd
    = (struct expand_loc_callback_data *) data;
  location_chain *loc, *next;
  rtx result = NULL;
  int first_child, result_first_child, last_child;
  bool pending_recursion;
  rtx loc_from = NULL;
  struct elt_loc_list *cloc = NULL;
  expand_depth depth = { 0, 0 }, saved_depth = elcd->depth;
  int wanted_entryvals, found_entryvals = 0;

  /* Clear all backlinks pointing at this, so that we're not notified
     while we're active.  */
  loc_exp_dep_clear (var);

 retry:
  if (var->onepart == ONEPART_VALUE)
    {
      cselib_val *val = CSELIB_VAL_PTR (dv_as_value (var->dv));

// WDS test
//      gcc_checking_assert (cselib_preserved_value_p (val));

      cloc = val->locs;
    }