re PR middle-end/36811 (endless (?) loop building with -O3)

2008-07-13  Richard Guenther  <rguenther@suse.de>

	PR middle-end/36811
	* langhooks.c (lhd_print_error_function): Deal with recursive
	BLOCK trees.

From-SVN: r137754

gcc/ChangeLog

+2008-07-13  Richard Guenther  <rguenther@suse.de>
+
+	PR middle-end/36811
+	* langhooks.c (lhd_print_error_function): Deal with recursive
+	BLOCK trees.
+
 2008-07-12  Jan Hubicka  <jh@suse.cz>
 
 	* cgraph.c (assembler_name_hash): New static var.

gcc/langhooks.c

@@ -394,7 +394,9 @@ lhd_print_error_function (diagnostic_context *context, const char *file,
 	  if (abstract_origin)
 	    {
 	      ao = BLOCK_ABSTRACT_ORIGIN (abstract_origin);
-	      while (TREE_CODE (ao) == BLOCK && BLOCK_ABSTRACT_ORIGIN (ao))
+	      while (TREE_CODE (ao) == BLOCK
+		     && BLOCK_ABSTRACT_ORIGIN (ao)
+		     && BLOCK_ABSTRACT_ORIGIN (ao) != ao)
 		ao = BLOCK_ABSTRACT_ORIGIN (ao);
 	      gcc_assert (TREE_CODE (ao) == FUNCTION_DECL);
 	      fndecl = ao;
@@ -424,7 +426,9 @@ lhd_print_error_function (diagnostic_context *context, const char *file,
 		{
 		  ao = BLOCK_ABSTRACT_ORIGIN (block);
 
-		  while (TREE_CODE (ao) == BLOCK && BLOCK_ABSTRACT_ORIGIN (ao))
+		  while (TREE_CODE (ao) == BLOCK
+			 && BLOCK_ABSTRACT_ORIGIN (ao)
+			 && BLOCK_ABSTRACT_ORIGIN (ao) != ao)
 		    ao = BLOCK_ABSTRACT_ORIGIN (ao);
 
 		  if (TREE_CODE (ao) == FUNCTION_DECL)