re PR lto/48492 (LTO bootstrap failure in copy_constant)

	PR lto/48492
	* dwarf2out.c (dwarf2out_finish): Do not attach a DIE on the limbo list
	to a NULL parent.

From-SVN: r175533

gcc/ChangeLog

+2011-06-27  Eric Botcazou  <ebotcazou@adacore.com>
+
+	PR lto/48492
+	* dwarf2out.c (dwarf2out_finish): Do not attach a DIE on the limbo list
+	to a NULL parent.
+
 2011-06-27  Richard Guenther  <rguenther@suse.de>
 
 	PR tree-optimization/49394

gcc/dwarf2out.c

@@ -25017,7 +25017,7 @@ dwarf2out_finish (const char *filename)
 	{
 	  dw_die_ref origin = get_AT_ref (die, DW_AT_abstract_origin);
 
-	  if (origin)
+	  if (origin && origin->die_parent)
 	    add_child_die (origin->die_parent, die);
 	  else if (is_cu_die (die))
 	    ;