friend.c (is_friend): Fix access control for local classes.

	* friend.c (is_friend): Fix access control for local classes.
	* class.c (is_empty_class): New fn.
	* call.c (build_call): Don't pass empty class objects to a function.

From-SVN: r18933

1 files changed, 17 insertions, 1 deletions

diff --git a/gcc/cp/call.c b/gcc/cp/call.c
index ab3e05e..dc5957d 100644
--- a/gcc/cp/call.c
+++ b/gcc/cp/call.c
@@ -24,11 +24,12 @@ Boston, MA 02111-1307, USA.  */
 /* High-level class interface.  */
 
 #include "config.h"
-#include "tree.h"
 #include "system.h"
+#include "tree.h"
 #include "cp-tree.h"
 #include "output.h"
 #include "flags.h"
+#include "rtl.h"
 
 #include "obstack.h"
 #define obstack_chunk_alloc xmalloc
@@ -492,6 +493,7 @@ build_call (function, result_type, parms)
      tree function, result_type, parms;
 {
   int is_constructor = 0;
+  tree tmp;
 
   function = build_addr_func (function);
 
@@ -506,6 +508,20 @@ build_call (function, result_type, parms)
       && DECL_CONSTRUCTOR_P (TREE_OPERAND (function, 0)))
     is_constructor = 1;
 
+  /* Don't actually pass empty class objects to a function.  This is useful
+     for tags in STL, which are used to control overload resolution.
+     We don't need to handle other cases of copying empty classes.  */
+  for (tmp = parms; tmp; tmp = TREE_CHAIN (tmp))
+    if (is_empty_class (TREE_TYPE (TREE_VALUE (tmp)))
+	&& ! TREE_ADDRESSABLE (TREE_TYPE (TREE_VALUE (tmp))))
+      {
+	tree t = make_node (RTL_EXPR);
+	TREE_TYPE (t) = TREE_TYPE (TREE_VALUE (tmp));
+	RTL_EXPR_RTL (t) = const0_rtx;
+	RTL_EXPR_SEQUENCE (t) = NULL_RTX;
+	TREE_VALUE (tmp) = t;
+      }
+
   function = build_nt (CALL_EXPR, function, parms, NULL_TREE);
   TREE_HAS_CONSTRUCTOR (function) = is_constructor;
   TREE_TYPE (function) = result_type;