Implement DR 209

cp:
	Implement DR 209
	* cp-tree.h (skip_type_access_control,
	reset_type_access_control): Prototype.
	* decl.c (grokdeclarator): Access of friends is not checked.
	* parse.y (component_decl_list): Reset type access control.
	* semantics.c (decl_type_access_control): Clear
	current_type_lookups.
	(save_type_access_control): Don't save if not deferring.
	(skip_type_access_control, reset_type_access_control): New
	functions.
	(begin_class_definition): Do type access control for basetypes.
	Start deferred access control.
	(finish_class_definition): Resume immediate access control if
	this is a local class.
testsuite:
	* g++.old-deja/g++.other/friend12.C: New test.
	* g++.old-deja/g++.other/friend9.C: Expect no errors.
	* g++.old-deja/g++.robertl/eb56.C: Make typedef public.

From-SVN: r40841

gcc/cp/ChangeLog

+2001-03-26  Nathan Sidwell  <nathan@codesourcery.com>
+
+	Implement DR 209
+	* cp-tree.h (skip_type_access_control,
+	reset_type_access_control): Prototype.
+	* decl.c (grokdeclarator): Access of friends is not checked.
+	* parse.y (component_decl_list): Reset type access control.
+	* semantics.c (decl_type_access_control): Clear
+	current_type_lookups.
+	(save_type_access_control): Don't save if not deferring.
+	(skip_type_access_control, reset_type_access_control): New
+	functions.
+	(begin_class_definition): Do type access control for basetypes.
+	Start deferred access control.
+	(finish_class_definition): Resume immediate access control if
+	this is a local class.
+
 2001-03-25  Kaveh R. Ghazi  <ghazi@caip.rutgers.edu>
 
 	* class.c (add_method): Use memcpy/memmove, not bcopy.

gcc/cp/cp-tree.h

@@ -4175,6 +4175,8 @@ extern tree get_binfo				PARAMS ((tree, tree, int));
 extern int get_base_distance			PARAMS ((tree, tree, int, tree *));
 extern tree get_dynamic_cast_base_type          PARAMS ((tree, tree));
 extern void type_access_control			PARAMS ((tree, tree));
+extern void skip_type_access_control            PARAMS ((void));
+extern void reset_type_access_control           PARAMS ((void));
 extern int accessible_p                         PARAMS ((tree, tree));
 extern tree lookup_field			PARAMS ((tree, tree, int, int));
 extern int lookup_fnfields_1                    PARAMS ((tree, tree));

gcc/cp/decl.c

@@ -11131,7 +11131,9 @@ friend declaration requires class-key, i.e. `friend %#T'",
 	  /* Only try to do this stuff if we didn't already give up.  */
 	  if (type != integer_type_node)
 	    {
-	      decl_type_access_control (TYPE_NAME (type));
+	      /* DR 209. The friendly class does not need to be accessible
+                 in the scope of the class granting friendship. */
+	      skip_type_access_control ();
 
 	      /* A friendly class?  */
 	      if (current_class_type)
@@ -11393,32 +11395,33 @@ friend declaration requires class-key, i.e. `friend %#T'",
 	if (friendp)
 	  {
 	    /* Friends are treated specially.  */
+            tree t = NULL_TREE;
+	    
+	    /* DR 209. The friend does not need to be accessible at this
+               point. */
+	    skip_type_access_control ();
+	    
 	    if (ctype == current_class_type)
 	      warning ("member functions are implicitly friends of their class");
-	    else
-	      {
-		tree t = NULL_TREE;
-		if (decl && DECL_NAME (decl))
-		  {
-		    if (template_class_depth (current_class_type) == 0)
-		      {
-			decl
-			  = check_explicit_specialization
-			  (declarator, decl,
-			   template_count, 2 * (funcdef_flag != 0) + 4);
-			if (decl == error_mark_node)
-			  return error_mark_node;
-		      }
 
-		    t = do_friend (ctype, declarator, decl,
-				   last_function_parms, attrlist, flags, quals,
-				   funcdef_flag);
-		  }
-		if (t && funcdef_flag)
-		  return t;
-
-		return void_type_node;
-	      }
+            if (decl && DECL_NAME (decl))
+              {
+                if (template_class_depth (current_class_type) == 0)
+                  {
+              	    decl = check_explicit_specialization
+              	            (declarator, decl,
+              	             template_count, 2 * (funcdef_flag != 0) + 4);
+              	    if (decl == error_mark_node)
+              	      return error_mark_node;
+                  }
+              
+                t = do_friend (ctype, declarator, decl,
+              		       last_function_parms, attrlist, flags, quals,
+              		       funcdef_flag);
+              }
+            if (t && funcdef_flag)
+              return t;
+	    return void_type_node;
 	  }
 
 	/* Structure field.  It may not be a function, except for C++ */

gcc/cp/parse.y

@@ -2548,11 +2548,13 @@ component_decl_list:
 		{ 
 		  finish_member_declaration ($1);
 		  current_aggr = NULL_TREE;
+		  reset_type_access_control ();
 		}
 	| component_decl_list component_decl
 		{ 
 		  finish_member_declaration ($2);
 		  current_aggr = NULL_TREE;
+		  reset_type_access_control ();
 		}
 	;
 

gcc/cp/semantics.c

@@ -1593,13 +1593,41 @@ decl_type_access_control (decl)
      added to type_lookups after typed_declspecs saved the copy that
      ended up in current_type_lookups.  */
   type_lookups = current_type_lookups;
+  
+  current_type_lookups = NULL_TREE;
 }
 
+/* Record the lookups, if we're doing deferred access control.  */
+
 void
 save_type_access_control (lookups)
      tree lookups;
 {
-  current_type_lookups = lookups;
+  if (type_lookups != error_mark_node)
+    {
+      my_friendly_assert (!current_type_lookups, 20010301);
+      current_type_lookups = lookups;
+    }
+  else
+    my_friendly_assert (!lookups || lookups == error_mark_node, 20010301);
+}
+
+/* Set things up so that the next deferred access control will succeed.
+   This is needed for friend declarations see grokdeclarator for details.  */
+
+void
+skip_type_access_control ()
+{
+  type_lookups = NULL_TREE;
+}
+
+/* Reset the deferred access control.  */
+
+void
+reset_type_access_control ()
+{
+  type_lookups = NULL_TREE;
+  current_type_lookups = NULL_TREE;
 }
 
 /* Begin a function definition declared with DECL_SPECS and
@@ -1732,6 +1760,10 @@ tree
 begin_class_definition (t)
      tree t;
 {
+  /* Check the bases are accessible. */
+  decl_type_access_control (TYPE_NAME (t));
+  reset_type_access_control ();
+  
   if (processing_template_parmlist)
     {
       cp_error ("definition of `%#T' inside template parameter list", t);
@@ -1953,6 +1985,8 @@ finish_class_definition (t, attributes, semi, pop_scope_p)
     check_for_missing_semicolon (t); 
   if (pop_scope_p)
     pop_scope (CP_DECL_CONTEXT (TYPE_MAIN_DECL (t)));
+  if (current_function_decl)
+    type_lookups = error_mark_node;
   if (current_scope () == current_function_decl)
     do_pending_defargs ();
 

gcc/testsuite/ChangeLog

+2001-03-26  Nathan Sidwell  <nathan@codesourcery.com>
+
+	* g++.old-deja/g++.other/friend12.C: New test.
+	* g++.old-deja/g++.other/friend9.C: Expect no errors.
+	* g++.old-deja/g++.robertl/eb56.C: Make typedef public.
+
 2001-03-25  Joseph S. Myers  <jsm28@cam.ac.uk>
 
 	* gcc.c-torture/execute/20010325-1.c: New test.

gcc/testsuite/g++.old-deja/g++.other/friend12.C

+// Build don't link:
+
+// Copyright (C) 2001 Free Software Foundation, Inc.
+// Contributed by Nathan Sidwell 1 Mar 2001 <nathan@codesourcery.com>
+
+// DR 209. friend access is not checked.
+
+class Z;
+class A
+{
+  class Inner {}; // ERROR - private
+  Inner f (Inner);
+  public:
+  A ();
+  friend class Z;
+};
+
+class B
+{
+  A::Inner j ();    // ERROR - private
+  A::Inner k ();    // ERROR - private
+  friend A::Inner A::f (Inner);
+  int t;
+  friend class A::Inner;
+};
+
+A::Inner l ();    // ERROR - private
+A::Inner m ();    // ERROR - private
+A::Inner a,       // ERROR - private
+         b;       // ERROR - private
+A::Inner a1;      // ERROR - private
+int b2;
+
+A::Inner A::f (Inner)
+{
+  B b;
+  b.t = 1;
+  return A::Inner ();
+}
+
+void Foo ()
+{
+  A::Inner i;  // ERROR - private
+  class Local
+  {
+    friend A::Inner A::f (Inner);
+    A::Inner k; // ERROR - private
+  };
+  class Local1 : A::Inner
+  { // ERROR - private
+    
+  };
+  A::Inner k;  // ERROR - private
+}
+
+class X : A::Inner
+{  // ERROR - private
+  class I : A::Inner
+  {  // ERROR - private
+    
+  };
+};
+
+class Z : A::Inner
+{  // ERROR - private
+  class I : A::Inner
+  { // ok, the base A::Inner is in the scope of Z which is a friend of A
+    
+  };
+};
+int b4;

gcc/testsuite/g++.old-deja/g++.other/friend9.C

@@ -5,14 +5,16 @@
 
 // Bug 853: We reported the wrong line no for a friend access violation
 
+// Since DR 209, friend declaration access is not checked.
+
 class F
 {
-  class Internal;   // ERROR - is private
+  class Internal;
 };
 
 class C
 {
-  friend class F::Internal; // ERROR - in this context
+  friend class F::Internal;
   public:
   typedef enum { A, B } e;
 

gcc/testsuite/g++.old-deja/g++.robertl/eb56.C

@@ -2,6 +2,7 @@
 // Build don't link:
 
 class foo {
+  public:
         typedef int sometype;
 };