2012-01-25  Jakub Jelinek  <jakub@redhat.com>

	PR debug/51950
	* dwarf2out.c (clone_tree_hash): New function.
	(copy_decls_walk): Use it instead of clone_tree.

--- gcc/dwarf2out.c.jj	2012-01-23 18:23:45.000000000 +0100
+++ gcc/dwarf2out.c	2012-01-25 18:32:24.026350399 +0100
@@ -7406,6 +7406,32 @@ copy_ancestor_tree (dw_die_ref unit, dw_
   return copy;
 }
 
+/* Like clone_tree, but additionally enter all the children into
+   the hash table decl_table.  */
+
+static dw_die_ref
+clone_tree_hash (dw_die_ref die, htab_t decl_table)
+{
+  dw_die_ref c;
+  dw_die_ref clone = clone_die (die);
+  struct decl_table_entry *entry;
+  void **slot = htab_find_slot_with_hash (decl_table, die,
+					  htab_hash_pointer (die), INSERT);
+  /* Assert that DIE isn't in the hash table yet.  If it would be there
+     before, the ancestors would be necessarily there as well, therefore
+     clone_tree_hash wouldn't be called.  */
+  gcc_assert (*slot == HTAB_EMPTY_ENTRY);
+  entry = XCNEW (struct decl_table_entry);
+  entry->orig = die;
+  entry->copy = clone;
+  *slot = entry;
+
+  FOR_EACH_CHILD (die, c,
+		  add_child_die (clone, clone_tree_hash (c, decl_table)));
+
+  return clone;
+}
+
 /* Walk the DIE and its children, looking for references to incomplete
    or trivial types that are unmarked (i.e., that are not in the current
    type_unit).  */
@@ -7442,7 +7468,11 @@ copy_decls_walk (dw_die_ref unit, dw_die
           else
             {
               dw_die_ref parent = unit;
-              dw_die_ref copy = clone_tree (targ);
+	      dw_die_ref copy = clone_die (targ);
+
+	      FOR_EACH_CHILD (targ, c,
+			      add_child_die (copy,
+					     clone_tree_hash (c, decl_table)));
 
               /* Make sure the cloned tree is marked as part of the
                  type unit.  */