/* { dg-do compile } */
/* { dg-options "-O1 -fno-tree-fre -fdump-tree-dom2" } */

extern void abort (void);
union tree_node;
typedef union tree_node *tree;
enum tree_code
{
  LAST_AND_UNUSED_TREE_CODE
};
extern const char tree_code_type[];
struct tree_common
{
  enum tree_code code:8;
};
struct tree_type
{
  struct tree_common common;
  double alias_set;
};
union tree_node
{
  struct tree_common common;
  struct tree_type type;
};
long
foo (t, set)
     tree t;
     double set;
{
  if (tree_code_type[t->common.code] != 't')
    abort ();

  t->type.alias_set = set;

  if (t->common.code == 42)
    return 1;
  else
    return 0;
}
/* There should be precisely one load of common.code.  If there is
   more than one, then the dominator optimizations failed.  */
/* { dg-final { scan-tree-dump-times "common.code" 1 "dom2" } } */