Index: ChangeLog
===================================================================
--- ChangeLog	(revision 247591)
+++ ChangeLog	(working copy)
@@ -1,3 +1,8 @@
+2017-05-04  Nathan Sidwell  <nathan@acm.org>
+
+	* name-lookup.c: Reorder functions to make merging from modules
+	branch simpler.
+
 2017-05-03  Jason Merrill  <jason@redhat.com>
 
 	* constexpr.c (cxx_eval_outermost_constant_expr): Use TV_CONSTEXPR.
Index: name-lookup.c
===================================================================
--- name-lookup.c	(revision 247591)
+++ name-lookup.c	(working copy)
@@ -33,6 +33,10 @@ along with GCC; see the file COPYING3.
 #include "spellcheck-tree.h"
 #include "parser.h"
 
+static cxx_binding *cxx_binding_make (tree value, tree type);
+static cp_binding_level *innermost_nonclass_level (void);
+static void set_identifier_type_value_with_scope (tree id, tree decl,
+						  cp_binding_level *b);
 /* The bindings for a particular name in a particular scope.  */
 
 struct scope_binding {
@@ -41,7 +45,6 @@ struct scope_binding {
 };
 #define EMPTY_SCOPE_BINDING { NULL_TREE, NULL_TREE }
 
-static cp_binding_level *innermost_nonclass_level (void);
 static cxx_binding *binding_for_name (cp_binding_level *, tree);
 static tree push_overloaded_decl (tree, int, bool);
 static bool lookup_using_namespace (tree, struct scope_binding *, tree,
@@ -66,6029 +69,5880 @@ tree global_namespace;
    unit.  */
 static GTY(()) tree anonymous_namespace_name;
 
-/* Initialize anonymous_namespace_name if necessary, and return it.  */
+/* Add DECL to the list of things declared in B.  */
 
-static tree
-get_anonymous_namespace_name (void)
+static void
+add_decl_to_level (tree decl, cp_binding_level *b)
 {
-  if (!anonymous_namespace_name)
+  /* We used to record virtual tables as if they were ordinary
+     variables, but no longer do so.  */
+  gcc_assert (!(VAR_P (decl) && DECL_VIRTUAL_P (decl)));
+
+  if (TREE_CODE (decl) == NAMESPACE_DECL
+      && !DECL_NAMESPACE_ALIAS (decl))
     {
-      /* We used to use get_file_function_name here, but that isn't
-	 necessary now that anonymous namespace typeinfos
-	 are !TREE_PUBLIC, and thus compared by address.  */
-      /* The demangler expects anonymous namespaces to be called
-	 something starting with '_GLOBAL__N_'.  */
-      anonymous_namespace_name = get_identifier ("_GLOBAL__N_1");
+      DECL_CHAIN (decl) = b->namespaces;
+      b->namespaces = decl;
     }
-  return anonymous_namespace_name;
-}
-
-/* Compute the chain index of a binding_entry given the HASH value of its
-   name and the total COUNT of chains.  COUNT is assumed to be a power
-   of 2.  */
-
-#define ENTRY_INDEX(HASH, COUNT) (((HASH) >> 3) & ((COUNT) - 1))
+  else
+    {
+      /* We build up the list in reverse order, and reverse it later if
+	 necessary.  */
+      TREE_CHAIN (decl) = b->names;
+      b->names = decl;
 
-/* A free list of "binding_entry"s awaiting for re-use.  */
+      /* If appropriate, add decl to separate list of statics.  We
+	 include extern variables because they might turn out to be
+	 static later.  It's OK for this list to contain a few false
+	 positives.  */
+      if (b->kind == sk_namespace)
+	if ((VAR_P (decl)
+	     && (TREE_STATIC (decl) || DECL_EXTERNAL (decl)))
+	    || (TREE_CODE (decl) == FUNCTION_DECL
+		&& (!TREE_PUBLIC (decl)
+		    || decl_anon_ns_mem_p (decl)
+		    || DECL_DECLARED_INLINE_P (decl))))
+	  vec_safe_push (b->static_decls, decl);
+    }
+}
 
-static GTY((deletable)) binding_entry free_binding_entry = NULL;
+/* [basic.lookup.koenig] */
+/* A nonzero return value in the functions below indicates an error.  */
 
-/* The binding oracle; see cp-tree.h.  */
+struct arg_lookup
+{
+  tree name;
+  vec<tree, va_gc> *args;
+  vec<tree, va_gc> *namespaces;
+  vec<tree, va_gc> *classes;
+  tree functions;
+  hash_set<tree> *fn_set;
+};
 
-cp_binding_oracle_function *cp_binding_oracle;
+static bool arg_assoc (struct arg_lookup*, tree);
+static bool arg_assoc_args (struct arg_lookup*, tree);
+static bool arg_assoc_args_vec (struct arg_lookup*, vec<tree, va_gc> *);
+static bool arg_assoc_type (struct arg_lookup*, tree);
+static bool add_function (struct arg_lookup *, tree);
+static bool arg_assoc_namespace (struct arg_lookup *, tree);
+static bool arg_assoc_class_only (struct arg_lookup *, tree);
+static bool arg_assoc_bases (struct arg_lookup *, tree);
+static bool arg_assoc_class (struct arg_lookup *, tree);
+static bool arg_assoc_template_arg (struct arg_lookup*, tree);
 
-/* If we have a binding oracle, ask it for all namespace-scoped
-   definitions of NAME.  */
+/* Add a function to the lookup structure.
+   Returns true on error.  */
 
-static inline void
-query_oracle (tree name)
+static bool
+add_function (struct arg_lookup *k, tree fn)
 {
-  if (!cp_binding_oracle)
-    return;
-
-  /* LOOKED_UP holds the set of identifiers that we have already
-     looked up with the oracle.  */
-  static hash_set<tree> looked_up;
-  if (looked_up.add (name))
-    return;
+  if (!is_overloaded_fn (fn))
+    /* All names except those of (possibly overloaded) functions and
+       function templates are ignored.  */;
+  else if (k->fn_set && k->fn_set->add (fn))
+    /* It's already in the list.  */;
+  else if (!k->functions && TREE_CODE (fn) != TEMPLATE_DECL)
+    k->functions = fn;
+  else if (fn == k->functions)
+    ;
+  else
+    {
+      k->functions = build_overload (fn, k->functions);
+      if (TREE_CODE (k->functions) == OVERLOAD)
+	OVL_ARG_DEPENDENT (k->functions) = true;
+    }
 
-  cp_binding_oracle (CP_ORACLE_IDENTIFIER, name);
+  return false;
 }
 
-/* Create a binding_entry object for (NAME, TYPE).  */
+/* Returns true iff CURRENT has declared itself to be an associated
+   namespace of SCOPE via a strong using-directive (or transitive chain
+   thereof).  Both are namespaces.  */
 
-static inline binding_entry
-binding_entry_make (tree name, tree type)
+bool
+is_associated_namespace (tree current, tree scope)
 {
-  binding_entry entry;
+  vec<tree, va_gc> *seen = make_tree_vector ();
+  vec<tree, va_gc> *todo = make_tree_vector ();
+  tree t;
+  bool ret;
 
-  if (free_binding_entry)
+  while (1)
     {
-      entry = free_binding_entry;
-      free_binding_entry = entry->chain;
+      if (scope == current)
+	{
+	  ret = true;
+	  break;
+	}
+      vec_safe_push (seen, scope);
+      for (t = DECL_NAMESPACE_ASSOCIATIONS (scope); t; t = TREE_CHAIN (t))
+	if (!vec_member (TREE_PURPOSE (t), seen))
+	  vec_safe_push (todo, TREE_PURPOSE (t));
+      if (!todo->is_empty ())
+	{
+	  scope = todo->last ();
+	  todo->pop ();
+	}
+      else
+	{
+	  ret = false;
+	  break;
+	}
     }
-  else
-    entry = ggc_alloc<binding_entry_s> ();
-
-  entry->name = name;
-  entry->type = type;
-  entry->chain = NULL;
 
-  return entry;
-}
+  release_tree_vector (seen);
+  release_tree_vector (todo);
 
-/* Put ENTRY back on the free list.  */
-#if 0
-static inline void
-binding_entry_free (binding_entry entry)
-{
-  entry->name = NULL;
-  entry->type = NULL;
-  entry->chain = free_binding_entry;
-  free_binding_entry = entry;
+  return ret;
 }
-#endif
-
-/* The datatype used to implement the mapping from names to types at
-   a given scope.  */
-struct GTY(()) binding_table_s {
-  /* Array of chains of "binding_entry"s  */
-  binding_entry * GTY((length ("%h.chain_count"))) chain;
 
-  /* The number of chains in this table.  This is the length of the
-     member "chain" considered as an array.  */
-  size_t chain_count;
+/* Add functions of a namespace to the lookup structure.
+   Returns true on error.  */
 
-  /* Number of "binding_entry"s in this table.  */
-  size_t entry_count;
-};
+static bool
+arg_assoc_namespace (struct arg_lookup *k, tree scope)
+{
+  tree value;
 
-/* Construct TABLE with an initial CHAIN_COUNT.  */
+  if (vec_member (scope, k->namespaces))
+    return false;
+  vec_safe_push (k->namespaces, scope);
 
-static inline void
-binding_table_construct (binding_table table, size_t chain_count)
-{
-  table->chain_count = chain_count;
-  table->entry_count = 0;
-  table->chain = ggc_cleared_vec_alloc<binding_entry> (table->chain_count);
-}
+  /* Check out our super-users.  */
+  for (value = DECL_NAMESPACE_ASSOCIATIONS (scope); value;
+       value = TREE_CHAIN (value))
+    if (arg_assoc_namespace (k, TREE_PURPOSE (value)))
+      return true;
 
-/* Make TABLE's entries ready for reuse.  */
-#if 0
-static void
-binding_table_free (binding_table table)
-{
-  size_t i;
-  size_t count;
+  /* Also look down into inline namespaces.  */
+  for (value = DECL_NAMESPACE_USING (scope); value;
+       value = TREE_CHAIN (value))
+    if (is_associated_namespace (scope, TREE_PURPOSE (value)))
+      if (arg_assoc_namespace (k, TREE_PURPOSE (value)))
+	return true;
 
-  if (table == NULL)
-    return;
+  value = namespace_binding (k->name, scope);
+  if (!value)
+    return false;
 
-  for (i = 0, count = table->chain_count; i < count; ++i)
+  for (; value; value = OVL_NEXT (value))
     {
-      binding_entry temp = table->chain[i];
-      while (temp != NULL)
-	{
-	  binding_entry entry = temp;
-	  temp = entry->chain;
-	  binding_entry_free (entry);
-	}
-      table->chain[i] = NULL;
-    }
-  table->entry_count = 0;
-}
-#endif
+      /* We don't want to find arbitrary hidden functions via argument
+	 dependent lookup.  We only want to find friends of associated
+	 classes, which we'll do via arg_assoc_class.  */
+      if (hidden_name_p (OVL_CURRENT (value)))
+	continue;
 
-/* Allocate a table with CHAIN_COUNT, assumed to be a power of two.  */
+      if (add_function (k, OVL_CURRENT (value)))
+	return true;
+    }
 
-static inline binding_table
-binding_table_new (size_t chain_count)
-{
-  binding_table table = ggc_alloc<binding_table_s> ();
-  table->chain = NULL;
-  binding_table_construct (table, chain_count);
-  return table;
+  return false;
 }
 
-/* Expand TABLE to twice its current chain_count.  */
+/* Adds everything associated with a template argument to the lookup
+   structure.  Returns true on error.  */
 
-static void
-binding_table_expand (binding_table table)
+static bool
+arg_assoc_template_arg (struct arg_lookup *k, tree arg)
 {
-  const size_t old_chain_count = table->chain_count;
-  const size_t old_entry_count = table->entry_count;
-  const size_t new_chain_count = 2 * old_chain_count;
-  binding_entry *old_chains = table->chain;
-  size_t i;
+  /* [basic.lookup.koenig]
 
-  binding_table_construct (table, new_chain_count);
-  for (i = 0; i < old_chain_count; ++i)
+     If T is a template-id, its associated namespaces and classes are
+     ... the namespaces and classes associated with the types of the
+     template arguments provided for template type parameters
+     (excluding template template parameters); the namespaces in which
+     any template template arguments are defined; and the classes in
+     which any member templates used as template template arguments
+     are defined.  [Note: non-type template arguments do not
+     contribute to the set of associated namespaces.  ]  */
+
+  /* Consider first template template arguments.  */
+  if (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
+      || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE)
+    return false;
+  else if (TREE_CODE (arg) == TEMPLATE_DECL)
     {
-      binding_entry entry = old_chains[i];
-      for (; entry != NULL; entry = old_chains[i])
-	{
-	  const unsigned int hash = IDENTIFIER_HASH_VALUE (entry->name);
-	  const size_t j = ENTRY_INDEX (hash, new_chain_count);
+      tree ctx = CP_DECL_CONTEXT (arg);
 
-	  old_chains[i] = entry->chain;
-	  entry->chain = table->chain[j];
-	  table->chain[j] = entry;
-	}
+      /* It's not a member template.  */
+      if (TREE_CODE (ctx) == NAMESPACE_DECL)
+	return arg_assoc_namespace (k, ctx);
+      /* Otherwise, it must be member template.  */
+      else
+	return arg_assoc_class_only (k, ctx);
     }
-  table->entry_count = old_entry_count;
+  /* It's an argument pack; handle it recursively.  */
+  else if (ARGUMENT_PACK_P (arg))
+    {
+      tree args = ARGUMENT_PACK_ARGS (arg);
+      int i, len = TREE_VEC_LENGTH (args);
+      for (i = 0; i < len; ++i) 
+	if (arg_assoc_template_arg (k, TREE_VEC_ELT (args, i)))
+	  return true;
+
+      return false;
+    }
+  /* It's not a template template argument, but it is a type template
+     argument.  */
+  else if (TYPE_P (arg))
+    return arg_assoc_type (k, arg);
+  /* It's a non-type template argument.  */
+  else
+    return false;
 }
 
-/* Insert a binding for NAME to TYPE into TABLE.  */
+/* Adds the class and its friends to the lookup structure.
+   Returns true on error.  */
 
-static void
-binding_table_insert (binding_table table, tree name, tree type)
+static bool
+arg_assoc_class_only (struct arg_lookup *k, tree type)
 {
-  const unsigned int hash = IDENTIFIER_HASH_VALUE (name);
-  const size_t i = ENTRY_INDEX (hash, table->chain_count);
-  binding_entry entry = binding_entry_make (name, type);
+  tree list, friends, context;
 
-  entry->chain = table->chain[i];
-  table->chain[i] = entry;
-  ++table->entry_count;
+  /* Backend-built structures, such as __builtin_va_list, aren't
+     affected by all this.  */
+  if (!CLASS_TYPE_P (type))
+    return false;
 
-  if (3 * table->chain_count < 5 * table->entry_count)
-    binding_table_expand (table);
-}
+  context = decl_namespace_context (type);
+  if (arg_assoc_namespace (k, context))
+    return true;
 
-/* Return the binding_entry, if any, that maps NAME.  */
+  complete_type (type);
 
-binding_entry
-binding_table_find (binding_table table, tree name)
-{
-  const unsigned int hash = IDENTIFIER_HASH_VALUE (name);
-  binding_entry entry = table->chain[ENTRY_INDEX (hash, table->chain_count)];
+  /* Process friends.  */
+  for (list = DECL_FRIENDLIST (TYPE_MAIN_DECL (type)); list;
+       list = TREE_CHAIN (list))
+    if (k->name == FRIEND_NAME (list))
+      for (friends = FRIEND_DECLS (list); friends;
+	   friends = TREE_CHAIN (friends))
+	{
+	  tree fn = TREE_VALUE (friends);
 
-  while (entry != NULL && entry->name != name)
-    entry = entry->chain;
+	  /* Only interested in global functions with potentially hidden
+	     (i.e. unqualified) declarations.  */
+	  if (CP_DECL_CONTEXT (fn) != context)
+	    continue;
+	  /* Template specializations are never found by name lookup.
+	     (Templates themselves can be found, but not template
+	     specializations.)  */
+	  if (TREE_CODE (fn) == FUNCTION_DECL && DECL_USE_TEMPLATE (fn))
+	    continue;
+	  if (add_function (k, fn))
+	    return true;
+	}
 
-  return entry;
+  return false;
 }
 
-/* Apply PROC -- with DATA -- to all entries in TABLE.  */
+/* Adds the class and its bases to the lookup structure.
+   Returns true on error.  */
 
-void
-binding_table_foreach (binding_table table, bt_foreach_proc proc, void *data)
+static bool
+arg_assoc_bases (struct arg_lookup *k, tree type)
 {
-  size_t chain_count;
-  size_t i;
-
-  if (!table)
-    return;
+  if (arg_assoc_class_only (k, type))
+    return true;
 
-  chain_count = table->chain_count;
-  for (i = 0; i < chain_count; ++i)
+  if (TYPE_BINFO (type))
     {
-      binding_entry entry = table->chain[i];
-      for (; entry != NULL; entry = entry->chain)
-	proc (entry, data);
-    }
-}
-
-#ifndef ENABLE_SCOPE_CHECKING
-#  define ENABLE_SCOPE_CHECKING 0
-#else
-#  define ENABLE_SCOPE_CHECKING 1
-#endif
-
-/* A free list of "cxx_binding"s, connected by their PREVIOUS.  */
-
-static GTY((deletable)) cxx_binding *free_bindings;
+      /* Process baseclasses.  */
+      tree binfo, base_binfo;
+      int i;
 
-/* Initialize VALUE and TYPE field for BINDING, and set the PREVIOUS
-   field to NULL.  */
+      for (binfo = TYPE_BINFO (type), i = 0;
+	   BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
+	if (arg_assoc_bases (k, BINFO_TYPE (base_binfo)))
+	  return true;
+    }
 
-static inline void
-cxx_binding_init (cxx_binding *binding, tree value, tree type)
-{
-  binding->value = value;
-  binding->type = type;
-  binding->previous = NULL;
+  return false;
 }
 
-/* (GC)-allocate a binding object with VALUE and TYPE member initialized.  */
+/* Adds everything associated with a class argument type to the lookup
+   structure.  Returns true on error.
 
-static cxx_binding *
-cxx_binding_make (tree value, tree type)
+   If T is a class type (including unions), its associated classes are: the
+   class itself; the class of which it is a member, if any; and its direct
+   and indirect base classes. Its associated namespaces are the namespaces
+   of which its associated classes are members. Furthermore, if T is a
+   class template specialization, its associated namespaces and classes
+   also include: the namespaces and classes associated with the types of
+   the template arguments provided for template type parameters (excluding
+   template template parameters); the namespaces of which any template
+   template arguments are members; and the classes of which any member
+   templates used as template template arguments are members. [ Note:
+   non-type template arguments do not contribute to the set of associated
+   namespaces.  --end note] */
+
+static bool
+arg_assoc_class (struct arg_lookup *k, tree type)
 {
-  cxx_binding *binding;
-  if (free_bindings)
-    {
-      binding = free_bindings;
-      free_bindings = binding->previous;
-    }
-  else
-    binding = ggc_alloc<cxx_binding> ();
+  tree list;
+  int i;
 
-  cxx_binding_init (binding, value, type);
+  /* Backend build structures, such as __builtin_va_list, aren't
+     affected by all this.  */
+  if (!CLASS_TYPE_P (type))
+    return false;
 
-  return binding;
-}
+  if (vec_member (type, k->classes))
+    return false;
+  vec_safe_push (k->classes, type);
 
-/* Put BINDING back on the free list.  */
+  if (TYPE_CLASS_SCOPE_P (type)
+      && arg_assoc_class_only (k, TYPE_CONTEXT (type)))
+    return true;
 
-static inline void
-cxx_binding_free (cxx_binding *binding)
-{
-  binding->scope = NULL;
-  binding->previous = free_bindings;
-  free_bindings = binding;
-}
+  if (arg_assoc_bases (k, type))
+    return true;
 
-/* Create a new binding for NAME (with the indicated VALUE and TYPE
-   bindings) in the class scope indicated by SCOPE.  */
+  /* Process template arguments.  */
+  if (CLASSTYPE_TEMPLATE_INFO (type)
+      && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (type)))
+    {
+      list = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type));
+      for (i = 0; i < TREE_VEC_LENGTH (list); ++i)
+	if (arg_assoc_template_arg (k, TREE_VEC_ELT (list, i)))
+	  return true;
+    }
 
-static cxx_binding *
-new_class_binding (tree name, tree value, tree type, cp_binding_level *scope)
-{
-  cp_class_binding cb = {cxx_binding_make (value, type), name};
-  cxx_binding *binding = cb.base;
-  vec_safe_push (scope->class_shadowed, cb);
-  binding->scope = scope;
-  return binding;
+  return false;
 }
 
-/* Make DECL the innermost binding for ID.  The LEVEL is the binding
-   level at which this declaration is being bound.  */
+/* Adds everything associated with a given type.
+   Returns 1 on error.  */
 
-void
-push_binding (tree id, tree decl, cp_binding_level* level)
+static bool
+arg_assoc_type (struct arg_lookup *k, tree type)
 {
-  cxx_binding *binding;
+  /* As we do not get the type of non-type dependent expressions
+     right, we can end up with such things without a type.  */
+  if (!type)
+    return false;
 
-  if (level != class_binding_level)
+  if (TYPE_PTRDATAMEM_P (type))
     {
-      binding = cxx_binding_make (decl, NULL_TREE);
-      binding->scope = level;
+      /* Pointer to member: associate class type and value type.  */
+      if (arg_assoc_type (k, TYPE_PTRMEM_CLASS_TYPE (type)))
+	return true;
+      return arg_assoc_type (k, TYPE_PTRMEM_POINTED_TO_TYPE (type));
     }
-  else
-    binding = new_class_binding (id, decl, /*type=*/NULL_TREE, level);
+  else switch (TREE_CODE (type))
+    {
+    case ERROR_MARK:
+      return false;
+    case VOID_TYPE:
+    case INTEGER_TYPE:
+    case REAL_TYPE:
+    case COMPLEX_TYPE:
+    case VECTOR_TYPE:
+    case BOOLEAN_TYPE:
+    case FIXED_POINT_TYPE:
+    case DECLTYPE_TYPE:
+    case NULLPTR_TYPE:
+      return false;
+    case RECORD_TYPE:
+      if (TYPE_PTRMEMFUNC_P (type))
+	return arg_assoc_type (k, TYPE_PTRMEMFUNC_FN_TYPE (type));
+      /* FALLTHRU */
+    case UNION_TYPE:
+      return arg_assoc_class (k, type);
+    case POINTER_TYPE:
+    case REFERENCE_TYPE:
+    case ARRAY_TYPE:
+      return arg_assoc_type (k, TREE_TYPE (type));
+    case ENUMERAL_TYPE:
+      if (TYPE_CLASS_SCOPE_P (type)
+	  && arg_assoc_class_only (k, TYPE_CONTEXT (type)))
+	return true;
+      return arg_assoc_namespace (k, decl_namespace_context (type));
+    case METHOD_TYPE:
+      /* The basetype is referenced in the first arg type, so just
+	 fall through.  */
+    case FUNCTION_TYPE:
+      /* Associate the parameter types.  */
+      if (arg_assoc_args (k, TYPE_ARG_TYPES (type)))
+	return true;
+      /* Associate the return type.  */
+      return arg_assoc_type (k, TREE_TYPE (type));
+    case TEMPLATE_TYPE_PARM:
+    case BOUND_TEMPLATE_TEMPLATE_PARM:
+      return false;
+    case TYPENAME_TYPE:
+      return false;
+    case LANG_TYPE:
+      gcc_assert (type == unknown_type_node
+		  || type == init_list_type_node);
+      return false;
+    case TYPE_PACK_EXPANSION:
+      return arg_assoc_type (k, PACK_EXPANSION_PATTERN (type));
 
-  /* Now, fill in the binding information.  */
-  binding->previous = IDENTIFIER_BINDING (id);
-  INHERITED_VALUE_BINDING_P (binding) = 0;
-  LOCAL_BINDING_P (binding) = (level != class_binding_level);
+    default:
+      gcc_unreachable ();
+    }
+  return false;
+}
 
-  /* And put it on the front of the list of bindings for ID.  */
-  IDENTIFIER_BINDING (id) = binding;
+/* Adds everything associated with arguments.  Returns true on error.  */
+
+static bool
+arg_assoc_args (struct arg_lookup *k, tree args)
+{
+  for (; args; args = TREE_CHAIN (args))
+    if (arg_assoc (k, TREE_VALUE (args)))
+      return true;
+  return false;
 }
 
-/* Remove the binding for DECL which should be the innermost binding
-   for ID.  */
+/* Adds everything associated with an argument vector.  Returns true
+   on error.  */
 
-void
-pop_binding (tree id, tree decl)
+static bool
+arg_assoc_args_vec (struct arg_lookup *k, vec<tree, va_gc> *args)
 {
-  cxx_binding *binding;
+  unsigned int ix;
+  tree arg;
 
-  if (id == NULL_TREE)
-    /* It's easiest to write the loops that call this function without
-       checking whether or not the entities involved have names.  We
-       get here for such an entity.  */
-    return;
+  FOR_EACH_VEC_SAFE_ELT (args, ix, arg)
+    if (arg_assoc (k, arg))
+      return true;
+  return false;
+}
 
-  /* Get the innermost binding for ID.  */
-  binding = IDENTIFIER_BINDING (id);
+/* Adds everything associated with a given tree_node.  Returns 1 on error.  */
 
-  /* The name should be bound.  */
-  gcc_assert (binding != NULL);
+static bool
+arg_assoc (struct arg_lookup *k, tree n)
+{
+  if (n == error_mark_node)
+    return false;
 
-  /* The DECL will be either the ordinary binding or the type
-     binding for this identifier.  Remove that binding.  */
-  if (binding->value == decl)
-    binding->value = NULL_TREE;
-  else
-    {
-      gcc_assert (binding->type == decl);
-      binding->type = NULL_TREE;
-    }
+  if (TYPE_P (n))
+    return arg_assoc_type (k, n);
 
-  if (!binding->value && !binding->type)
+  if (! type_unknown_p (n))
+    return arg_assoc_type (k, TREE_TYPE (n));
+
+  if (TREE_CODE (n) == ADDR_EXPR)
+    n = TREE_OPERAND (n, 0);
+  if (TREE_CODE (n) == COMPONENT_REF)
+    n = TREE_OPERAND (n, 1);
+  if (TREE_CODE (n) == OFFSET_REF)
+    n = TREE_OPERAND (n, 1);
+  while (TREE_CODE (n) == TREE_LIST)
+    n = TREE_VALUE (n);
+  if (BASELINK_P (n))
+    n = BASELINK_FUNCTIONS (n);
+
+  if (TREE_CODE (n) == FUNCTION_DECL)
+    return arg_assoc_type (k, TREE_TYPE (n));
+  if (TREE_CODE (n) == TEMPLATE_ID_EXPR)
     {
-      /* We're completely done with the innermost binding for this
-	 identifier.  Unhook it from the list of bindings.  */
-      IDENTIFIER_BINDING (id) = binding->previous;
+      /* The working paper doesn't currently say how to handle template-id
+	 arguments.  The sensible thing would seem to be to handle the list
+	 of template candidates like a normal overload set, and handle the
+	 template arguments like we do for class template
+	 specializations.  */
+      tree templ = TREE_OPERAND (n, 0);
+      tree args = TREE_OPERAND (n, 1);
+      int ix;
 
-      /* Add it to the free list.  */
-      cxx_binding_free (binding);
+      /* First the templates.  */
+      if (arg_assoc (k, templ))
+	return true;
+
+      /* Now the arguments.  */
+      if (args)
+	for (ix = TREE_VEC_LENGTH (args); ix--;)
+	  if (arg_assoc_template_arg (k, TREE_VEC_ELT (args, ix)) == 1)
+	    return true;
     }
+  else if (TREE_CODE (n) == OVERLOAD)
+    {
+      for (; n; n = OVL_NEXT (n))
+	if (arg_assoc_type (k, TREE_TYPE (OVL_CURRENT (n))))
+	  return true;
+    }
+
+  return false;
 }
 
-/* Remove the bindings for the decls of the current level and leave
-   the current scope.  */
+/* Performs Koenig lookup depending on arguments, where fns
+   are the functions found in normal lookup.  */
 
-void
-pop_bindings_and_leave_scope (void)
+static cp_expr
+lookup_arg_dependent_1 (tree name, tree fns, vec<tree, va_gc> *args)
 {
-  for (tree t = getdecls (); t; t = DECL_CHAIN (t))
-    pop_binding (DECL_NAME (t), t);
-  leave_scope ();
-}
+  struct arg_lookup k;
 
-/* Strip non dependent using declarations. If DECL is dependent,
-   surreptitiously create a typename_type and return it.  */
+  /* Remove any hidden friend functions from the list of functions
+     found so far.  They will be added back by arg_assoc_class as
+     appropriate.  */
+  fns = remove_hidden_names (fns);
 
-tree
-strip_using_decl (tree decl)
-{
-  if (decl == NULL_TREE)
-    return NULL_TREE;
+  k.name = name;
+  k.args = args;
+  k.functions = fns;
+  k.classes = make_tree_vector ();
 
-  while (TREE_CODE (decl) == USING_DECL && !DECL_DEPENDENT_P (decl))
-    decl = USING_DECL_DECLS (decl);
+  /* We previously performed an optimization here by setting
+     NAMESPACES to the current namespace when it was safe. However, DR
+     164 says that namespaces that were already searched in the first
+     stage of template processing are searched again (potentially
+     picking up later definitions) in the second stage. */
+  k.namespaces = make_tree_vector ();
 
-  if (TREE_CODE (decl) == USING_DECL && DECL_DEPENDENT_P (decl)
-      && USING_DECL_TYPENAME_P (decl))
+  /* We used to allow duplicates and let joust discard them, but
+     since the above change for DR 164 we end up with duplicates of
+     all the functions found by unqualified lookup.  So keep track
+     of which ones we've seen.  */
+  if (fns)
     {
-      /* We have found a type introduced by a using
-	 declaration at class scope that refers to a dependent
-	 type.
-	     
-	 using typename :: [opt] nested-name-specifier unqualified-id ;
-      */
-      decl = make_typename_type (TREE_TYPE (decl),
-				 DECL_NAME (decl),
-				 typename_type, tf_error);
-      if (decl != error_mark_node)
-	decl = TYPE_NAME (decl);
+      tree ovl;
+      /* We shouldn't be here if lookup found something other than
+	 namespace-scope functions.  */
+      gcc_assert (DECL_NAMESPACE_SCOPE_P (OVL_CURRENT (fns)));
+      k.fn_set = new hash_set<tree>;
+      for (ovl = fns; ovl; ovl = OVL_NEXT (ovl))
+	k.fn_set->add (OVL_CURRENT (ovl));
     }
+  else
+    k.fn_set = NULL;
 
-  return decl;
-}
+  arg_assoc_args_vec (&k, args);
 
-/* BINDING records an existing declaration for a name in the current scope.
-   But, DECL is another declaration for that same identifier in the
-   same scope.  This is the `struct stat' hack whereby a non-typedef
-   class name or enum-name can be bound at the same level as some other
-   kind of entity.
-   3.3.7/1
+  fns = k.functions;
+  
+  if (fns
+      && !VAR_P (fns)
+      && !is_overloaded_fn (fns))
+    {
+      error ("argument dependent lookup finds %q+D", fns);
+      error ("  in call to %qD", name);
+      fns = error_mark_node;
+    }
 
-     A class name (9.1) or enumeration name (7.2) can be hidden by the
-     name of an object, function, or enumerator declared in the same scope.
-     If a class or enumeration name and an object, function, or enumerator
-     are declared in the same scope (in any order) with the same name, the
-     class or enumeration name is hidden wherever the object, function, or
-     enumerator name is visible.
+  release_tree_vector (k.classes);
+  release_tree_vector (k.namespaces);
+  delete k.fn_set;
+    
+  return fns;
+}
 
-   It's the responsibility of the caller to check that
-   inserting this name is valid here.  Returns nonzero if the new binding
-   was successful.  */
+/* Wrapper for lookup_arg_dependent_1.  */
 
-static bool
-supplement_binding_1 (cxx_binding *binding, tree decl)
+cp_expr
+lookup_arg_dependent (tree name, tree fns, vec<tree, va_gc> *args)
 {
-  tree bval = binding->value;
-  bool ok = true;
-  tree target_bval = strip_using_decl (bval);
-  tree target_decl = strip_using_decl (decl);
+  cp_expr ret;
+  bool subtime;
+  subtime = timevar_cond_start (TV_NAME_LOOKUP);
+  ret = lookup_arg_dependent_1 (name, fns, args);
+  timevar_cond_stop (TV_NAME_LOOKUP, subtime);
+  return ret;
+}
 
-  if (TREE_CODE (target_decl) == TYPE_DECL && DECL_ARTIFICIAL (target_decl)
-      && target_decl != target_bval
-      && (TREE_CODE (target_bval) != TYPE_DECL
-	  /* We allow pushing an enum multiple times in a class
-	     template in order to handle late matching of underlying
-	     type on an opaque-enum-declaration followed by an
-	     enum-specifier.  */
-	  || (processing_template_decl
-	      && TREE_CODE (TREE_TYPE (target_decl)) == ENUMERAL_TYPE
-	      && TREE_CODE (TREE_TYPE (target_bval)) == ENUMERAL_TYPE
-	      && (dependent_type_p (ENUM_UNDERLYING_TYPE
-				    (TREE_TYPE (target_decl)))
-		  || dependent_type_p (ENUM_UNDERLYING_TYPE
-				       (TREE_TYPE (target_bval)))))))
-    /* The new name is the type name.  */
-    binding->type = decl;
-  else if (/* TARGET_BVAL is null when push_class_level_binding moves
-	      an inherited type-binding out of the way to make room
-	      for a new value binding.  */
-	   !target_bval
-	   /* TARGET_BVAL is error_mark_node when TARGET_DECL's name
-	      has been used in a non-class scope prior declaration.
-	      In that case, we should have already issued a
-	      diagnostic; for graceful error recovery purpose, pretend
-	      this was the intended declaration for that name.  */
-	   || target_bval == error_mark_node
-	   /* If TARGET_BVAL is anticipated but has not yet been
-	      declared, pretend it is not there at all.  */
-	   || (TREE_CODE (target_bval) == FUNCTION_DECL
-	       && DECL_ANTICIPATED (target_bval)
-	       && !DECL_HIDDEN_FRIEND_P (target_bval)))
-    binding->value = decl;
-  else if (TREE_CODE (target_bval) == TYPE_DECL
-	   && DECL_ARTIFICIAL (target_bval)
-	   && target_decl != target_bval
-	   && (TREE_CODE (target_decl) != TYPE_DECL
-	       || same_type_p (TREE_TYPE (target_decl),
-			       TREE_TYPE (target_bval))))
+/* Initialize anonymous_namespace_name if necessary, and return it.  */
+
+static tree
+get_anonymous_namespace_name (void)
+{
+  if (!anonymous_namespace_name)
     {
-      /* The old binding was a type name.  It was placed in
-	 VALUE field because it was thought, at the point it was
-	 declared, to be the only entity with such a name.  Move the
-	 type name into the type slot; it is now hidden by the new
-	 binding.  */
-      binding->type = bval;
-      binding->value = decl;
-      binding->value_is_inherited = false;
+      /* We used to use get_file_function_name here, but that isn't
+	 necessary now that anonymous namespace typeinfos
+	 are !TREE_PUBLIC, and thus compared by address.  */
+      /* The demangler expects anonymous namespaces to be called
+	 something starting with '_GLOBAL__N_'.  */
+      anonymous_namespace_name = get_identifier ("_GLOBAL__N_1");
     }
-  else if (TREE_CODE (target_bval) == TYPE_DECL
-	   && TREE_CODE (target_decl) == TYPE_DECL
-	   && DECL_NAME (target_decl) == DECL_NAME (target_bval)
-	   && binding->scope->kind != sk_class
-	   && (same_type_p (TREE_TYPE (target_decl), TREE_TYPE (target_bval))
-	       /* If either type involves template parameters, we must
-		  wait until instantiation.  */
-	       || uses_template_parms (TREE_TYPE (target_decl))
-	       || uses_template_parms (TREE_TYPE (target_bval))))
-    /* We have two typedef-names, both naming the same type to have
-       the same name.  In general, this is OK because of:
-
-	 [dcl.typedef]
+  return anonymous_namespace_name;
+}
 
-	 In a given scope, a typedef specifier can be used to redefine
-	 the name of any type declared in that scope to refer to the
-	 type to which it already refers.
+/* Compute the chain index of a binding_entry given the HASH value of its
+   name and the total COUNT of chains.  COUNT is assumed to be a power
+   of 2.  */
 
-       However, in class scopes, this rule does not apply due to the
-       stricter language in [class.mem] prohibiting redeclarations of
-       members.  */
-    ok = false;
-  /* There can be two block-scope declarations of the same variable,
-     so long as they are `extern' declarations.  However, there cannot
-     be two declarations of the same static data member:
+#define ENTRY_INDEX(HASH, COUNT) (((HASH) >> 3) & ((COUNT) - 1))
 
-       [class.mem]
+/* A free list of "binding_entry"s awaiting for re-use.  */
 
-       A member shall not be declared twice in the
-       member-specification.  */
-  else if (VAR_P (target_decl)
-	   && VAR_P (target_bval)
-	   && DECL_EXTERNAL (target_decl) && DECL_EXTERNAL (target_bval)
-	   && !DECL_CLASS_SCOPE_P (target_decl))
-    {
-      duplicate_decls (decl, binding->value, /*newdecl_is_friend=*/false);
-      ok = false;
-    }
-  else if (TREE_CODE (decl) == NAMESPACE_DECL
-	   && TREE_CODE (bval) == NAMESPACE_DECL
-	   && DECL_NAMESPACE_ALIAS (decl)
-	   && DECL_NAMESPACE_ALIAS (bval)
-	   && ORIGINAL_NAMESPACE (bval) == ORIGINAL_NAMESPACE (decl))
-    /* [namespace.alias]
+static GTY((deletable)) binding_entry free_binding_entry = NULL;
 
-      In a declarative region, a namespace-alias-definition can be
-      used to redefine a namespace-alias declared in that declarative
-      region to refer only to the namespace to which it already
-      refers.  */
-    ok = false;
-  else if (maybe_remove_implicit_alias (bval))
-    {
-      /* There was a mangling compatibility alias using this mangled name,
-	 but now we have a real decl that wants to use it instead.  */
-      binding->value = decl;
-    }
-  else
-    {
-      if (!error_operand_p (bval))
-	diagnose_name_conflict (decl, bval);
-      ok = false;
-    }
+/* The binding oracle; see cp-tree.h.  */
 
-  return ok;
-}
+cp_binding_oracle_function *cp_binding_oracle;
 
-/* Diagnose a name conflict between DECL and BVAL.  */
+/* If we have a binding oracle, ask it for all namespace-scoped
+   definitions of NAME.  */
 
-static void
-diagnose_name_conflict (tree decl, tree bval)
+static inline void
+query_oracle (tree name)
 {
-  if (TREE_CODE (decl) == TREE_CODE (bval)
-      && (TREE_CODE (decl) != TYPE_DECL
-	  || (DECL_ARTIFICIAL (decl) && DECL_ARTIFICIAL (bval))
-	  || (!DECL_ARTIFICIAL (decl) && !DECL_ARTIFICIAL (bval)))
-      && !is_overloaded_fn (decl))
-    error ("redeclaration of %q#D", decl);
-  else
-    error ("%q#D conflicts with a previous declaration", decl);
-
-  inform (location_of (bval), "previous declaration %q#D", bval);
-}
+  if (!cp_binding_oracle)
+    return;
 
-/* Wrapper for supplement_binding_1.  */
+  /* LOOKED_UP holds the set of identifiers that we have already
+     looked up with the oracle.  */
+  static hash_set<tree> looked_up;
+  if (looked_up.add (name))
+    return;
 
-static bool
-supplement_binding (cxx_binding *binding, tree decl)
-{
-  bool ret;
-  bool subtime = timevar_cond_start (TV_NAME_LOOKUP);
-  ret = supplement_binding_1 (binding, decl);
-  timevar_cond_stop (TV_NAME_LOOKUP, subtime);
-  return ret;
+  cp_binding_oracle (CP_ORACLE_IDENTIFIER, name);
 }
 
-/* Add DECL to the list of things declared in B.  */
+/* Create a binding_entry object for (NAME, TYPE).  */
 
-static void
-add_decl_to_level (tree decl, cp_binding_level *b)
+static inline binding_entry
+binding_entry_make (tree name, tree type)
 {
-  /* We used to record virtual tables as if they were ordinary
-     variables, but no longer do so.  */
-  gcc_assert (!(VAR_P (decl) && DECL_VIRTUAL_P (decl)));
+  binding_entry entry;
 
-  if (TREE_CODE (decl) == NAMESPACE_DECL
-      && !DECL_NAMESPACE_ALIAS (decl))
+  if (free_binding_entry)
     {
-      DECL_CHAIN (decl) = b->namespaces;
-      b->namespaces = decl;
+      entry = free_binding_entry;
+      free_binding_entry = entry->chain;
     }
   else
-    {
-      /* We build up the list in reverse order, and reverse it later if
-	 necessary.  */
-      TREE_CHAIN (decl) = b->names;
-      b->names = decl;
-
-      /* If appropriate, add decl to separate list of statics.  We
-	 include extern variables because they might turn out to be
-	 static later.  It's OK for this list to contain a few false
-	 positives.  */
-      if (b->kind == sk_namespace)
-	if ((VAR_P (decl)
-	     && (TREE_STATIC (decl) || DECL_EXTERNAL (decl)))
-	    || (TREE_CODE (decl) == FUNCTION_DECL
-		&& (!TREE_PUBLIC (decl)
-		    || decl_anon_ns_mem_p (decl)
-		    || DECL_DECLARED_INLINE_P (decl))))
-	  vec_safe_push (b->static_decls, decl);
-    }
-}
+    entry = ggc_alloc<binding_entry_s> ();
 
-/* Record a decl-node X as belonging to the current lexical scope.
-   Check for errors (such as an incompatible declaration for the same
-   name already seen in the same scope).  IS_FRIEND is true if X is
-   declared as a friend.
+  entry->name = name;
+  entry->type = type;
+  entry->chain = NULL;
 
-   Returns either X or an old decl for the same name.
-   If an old decl is returned, it may have been smashed
-   to agree with what X says.  */
+  return entry;
+}
 
-static tree
-pushdecl_maybe_friend_1 (tree x, bool is_friend)
+/* Put ENTRY back on the free list.  */
+#if 0
+static inline void
+binding_entry_free (binding_entry entry)
 {
-  tree t;
-  tree name;
-  int need_new_binding;
+  entry->name = NULL;
+  entry->type = NULL;
+  entry->chain = free_binding_entry;
+  free_binding_entry = entry;
+}
+#endif
 
-  if (x == error_mark_node)
-    return error_mark_node;
+/* The datatype used to implement the mapping from names to types at
+   a given scope.  */
+struct GTY(()) binding_table_s {
+  /* Array of chains of "binding_entry"s  */
+  binding_entry * GTY((length ("%h.chain_count"))) chain;
 
-  need_new_binding = 1;
+  /* The number of chains in this table.  This is the length of the
+     member "chain" considered as an array.  */
+  size_t chain_count;
 
-  if (DECL_TEMPLATE_PARM_P (x))
-    /* Template parameters have no context; they are not X::T even
-       when declared within a class or namespace.  */
-    ;
-  else
-    {
-      if (current_function_decl && x != current_function_decl
-	  /* A local declaration for a function doesn't constitute
-	     nesting.  */
-	  && TREE_CODE (x) != FUNCTION_DECL
-	  /* A local declaration for an `extern' variable is in the
-	     scope of the current namespace, not the current
-	     function.  */
-	  && !(VAR_P (x) && DECL_EXTERNAL (x))
-	  /* When parsing the parameter list of a function declarator,
-	     don't set DECL_CONTEXT to an enclosing function.  When we
-	     push the PARM_DECLs in order to process the function body,
-	     current_binding_level->this_entity will be set.  */
-	  && !(TREE_CODE (x) == PARM_DECL
-	       && current_binding_level->kind == sk_function_parms
-	       && current_binding_level->this_entity == NULL)
-	  && !DECL_CONTEXT (x))
-	DECL_CONTEXT (x) = current_function_decl;
+  /* Number of "binding_entry"s in this table.  */
+  size_t entry_count;
+};
 
-      /* If this is the declaration for a namespace-scope function,
-	 but the declaration itself is in a local scope, mark the
-	 declaration.  */
-      if (TREE_CODE (x) == FUNCTION_DECL
-	  && DECL_NAMESPACE_SCOPE_P (x)
-	  && current_function_decl
-	  && x != current_function_decl)
-	DECL_LOCAL_FUNCTION_P (x) = 1;
-    }
+/* Construct TABLE with an initial CHAIN_COUNT.  */
 
-  name = DECL_NAME (x);
-  if (name)
-    {
-      int different_binding_level = 0;
+static inline void
+binding_table_construct (binding_table table, size_t chain_count)
+{
+  table->chain_count = chain_count;
+  table->entry_count = 0;
+  table->chain = ggc_cleared_vec_alloc<binding_entry> (table->chain_count);
+}
 
-      if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
-	name = TREE_OPERAND (name, 0);
+/* Make TABLE's entries ready for reuse.  */
+#if 0
+static void
+binding_table_free (binding_table table)
+{
+  size_t i;
+  size_t count;
 
-      /* In case this decl was explicitly namespace-qualified, look it
-	 up in its namespace context.  */
-      if (DECL_NAMESPACE_SCOPE_P (x) && namespace_bindings_p ())
-	t = namespace_binding (name, DECL_CONTEXT (x));
-      else
-	t = lookup_name_innermost_nonclass_level (name);
+  if (table == NULL)
+    return;
 
-      /* [basic.link] If there is a visible declaration of an entity
-	 with linkage having the same name and type, ignoring entities
-	 declared outside the innermost enclosing namespace scope, the
-	 block scope declaration declares that same entity and
-	 receives the linkage of the previous declaration.  */
-      if (! t && current_function_decl && x != current_function_decl
-	  && VAR_OR_FUNCTION_DECL_P (x)
-	  && DECL_EXTERNAL (x))
+  for (i = 0, count = table->chain_count; i < count; ++i)
+    {
+      binding_entry temp = table->chain[i];
+      while (temp != NULL)
 	{
-	  /* Look in block scope.  */
-	  t = innermost_non_namespace_value (name);
-	  /* Or in the innermost namespace.  */
-	  if (! t)
-	    t = namespace_binding (name, DECL_CONTEXT (x));
-	  /* Does it have linkage?  Note that if this isn't a DECL, it's an
-	     OVERLOAD, which is OK.  */
-	  if (t && DECL_P (t) && ! (TREE_STATIC (t) || DECL_EXTERNAL (t)))
-	    t = NULL_TREE;
-	  if (t)
-	    different_binding_level = 1;
+	  binding_entry entry = temp;
+	  temp = entry->chain;
+	  binding_entry_free (entry);
 	}
+      table->chain[i] = NULL;
+    }
+  table->entry_count = 0;
+}
+#endif
 
-      /* If we are declaring a function, and the result of name-lookup
-	 was an OVERLOAD, look for an overloaded instance that is
-	 actually the same as the function we are declaring.  (If
-	 there is one, we have to merge our declaration with the
-	 previous declaration.)  */
-      if (t && TREE_CODE (t) == OVERLOAD)
-	{
-	  tree match;
+/* Allocate a table with CHAIN_COUNT, assumed to be a power of two.  */
 
-	  if (TREE_CODE (x) == FUNCTION_DECL)
-	    for (match = t; match; match = OVL_NEXT (match))
-	      {
-		if (decls_match (OVL_CURRENT (match), x))
-		  break;
-	      }
-	  else
-	    /* Just choose one.  */
-	    match = t;
+static inline binding_table
+binding_table_new (size_t chain_count)
+{
+  binding_table table = ggc_alloc<binding_table_s> ();
+  table->chain = NULL;
+  binding_table_construct (table, chain_count);
+  return table;
+}
 
-	  if (match)
-	    t = OVL_CURRENT (match);
-	  else
-	    t = NULL_TREE;
-	}
+/* Expand TABLE to twice its current chain_count.  */
 
-      if (t && t != error_mark_node)
+static void
+binding_table_expand (binding_table table)
+{
+  const size_t old_chain_count = table->chain_count;
+  const size_t old_entry_count = table->entry_count;
+  const size_t new_chain_count = 2 * old_chain_count;
+  binding_entry *old_chains = table->chain;
+  size_t i;
+
+  binding_table_construct (table, new_chain_count);
+  for (i = 0; i < old_chain_count; ++i)
+    {
+      binding_entry entry = old_chains[i];
+      for (; entry != NULL; entry = old_chains[i])
 	{
-	  if (different_binding_level)
-	    {
-	      if (decls_match (x, t))
-		/* The standard only says that the local extern
-		   inherits linkage from the previous decl; in
-		   particular, default args are not shared.  Add
-		   the decl into a hash table to make sure only
-		   the previous decl in this case is seen by the
-		   middle end.  */
-		{
-		  struct cxx_int_tree_map *h;
+	  const unsigned int hash = IDENTIFIER_HASH_VALUE (entry->name);
+	  const size_t j = ENTRY_INDEX (hash, new_chain_count);
 
-		  TREE_PUBLIC (x) = TREE_PUBLIC (t);
+	  old_chains[i] = entry->chain;
+	  entry->chain = table->chain[j];
+	  table->chain[j] = entry;
+	}
+    }
+  table->entry_count = old_entry_count;
+}
 
-		  if (cp_function_chain->extern_decl_map == NULL)
-		    cp_function_chain->extern_decl_map
-		      = hash_table<cxx_int_tree_map_hasher>::create_ggc (20);
+/* Insert a binding for NAME to TYPE into TABLE.  */
 
-		  h = ggc_alloc<cxx_int_tree_map> ();
-		  h->uid = DECL_UID (x);
-		  h->to = t;
-		  cxx_int_tree_map **loc = cp_function_chain->extern_decl_map
-		    ->find_slot (h, INSERT);
-		  *loc = h;
-		}
-	    }
-	  else if (TREE_CODE (t) == PARM_DECL)
-	    {
-	      /* Check for duplicate params.  */
-	      tree d = duplicate_decls (x, t, is_friend);
-	      if (d)
-		return d;
-	    }
-	  else if ((DECL_EXTERN_C_FUNCTION_P (x)
-		    || DECL_FUNCTION_TEMPLATE_P (x))
-		   && is_overloaded_fn (t))
-	    /* Don't do anything just yet.  */;
-	  else if (t == wchar_decl_node)
-	    {
-	      if (! DECL_IN_SYSTEM_HEADER (x))
-		pedwarn (input_location, OPT_Wpedantic, "redeclaration of %<wchar_t%> as %qT",
-			 TREE_TYPE (x));
-	      
-	      /* Throw away the redeclaration.  */
-	      return t;
-	    }
-	  else
-	    {
-	      tree olddecl = duplicate_decls (x, t, is_friend);
+static void
+binding_table_insert (binding_table table, tree name, tree type)
+{
+  const unsigned int hash = IDENTIFIER_HASH_VALUE (name);
+  const size_t i = ENTRY_INDEX (hash, table->chain_count);
+  binding_entry entry = binding_entry_make (name, type);
 
-	      /* If the redeclaration failed, we can stop at this
-		 point.  */
-	      if (olddecl == error_mark_node)
-		return error_mark_node;
+  entry->chain = table->chain[i];
+  table->chain[i] = entry;
+  ++table->entry_count;
 
-	      if (olddecl)
-		{
-		  if (TREE_CODE (t) == TYPE_DECL)
-		    SET_IDENTIFIER_TYPE_VALUE (name, TREE_TYPE (t));
+  if (3 * table->chain_count < 5 * table->entry_count)
+    binding_table_expand (table);
+}
 
-		  return t;
-		}
-	      else if (DECL_MAIN_P (x) && TREE_CODE (t) == FUNCTION_DECL)
-		{
-		  /* A redeclaration of main, but not a duplicate of the
-		     previous one.
+/* Return the binding_entry, if any, that maps NAME.  */
 
-		     [basic.start.main]
+binding_entry
+binding_table_find (binding_table table, tree name)
+{
+  const unsigned int hash = IDENTIFIER_HASH_VALUE (name);
+  binding_entry entry = table->chain[ENTRY_INDEX (hash, table->chain_count)];
 
-		     This function shall not be overloaded.  */
-		  error ("invalid redeclaration of %q+D", t);
-		  error ("as %qD", x);
-		  /* We don't try to push this declaration since that
-		     causes a crash.  */
-		  return x;
-		}
-	    }
-	}
+  while (entry != NULL && entry->name != name)
+    entry = entry->chain;
 
-      /* If x has C linkage-specification, (extern "C"),
-	 lookup its binding, in case it's already bound to an object.
-	 The lookup is done in all namespaces.
-	 If we find an existing binding, make sure it has the same
-	 exception specification as x, otherwise, bail in error [7.5, 7.6].  */
-      if ((TREE_CODE (x) == FUNCTION_DECL)
-	  && DECL_EXTERN_C_P (x)
-          /* We should ignore declarations happening in system headers.  */
-	  && !DECL_ARTIFICIAL (x)
-	  && !DECL_IN_SYSTEM_HEADER (x))
-	{
-	  tree previous = lookup_extern_c_fun_in_all_ns (x);
-	  if (previous
-	      && !DECL_ARTIFICIAL (previous)
-              && !DECL_IN_SYSTEM_HEADER (previous)
-	      && DECL_CONTEXT (previous) != DECL_CONTEXT (x))
-	    {
-	      /* In case either x or previous is declared to throw an exception,
-	         make sure both exception specifications are equal.  */
-	      if (decls_match (x, previous))
-		{
-		  tree x_exception_spec = NULL_TREE;
-		  tree previous_exception_spec = NULL_TREE;
-
-		  x_exception_spec =
-				TYPE_RAISES_EXCEPTIONS (TREE_TYPE (x));
-		  previous_exception_spec =
-				TYPE_RAISES_EXCEPTIONS (TREE_TYPE (previous));
-		  if (!comp_except_specs (previous_exception_spec,
-					  x_exception_spec,
-					  ce_normal))
-		    {
-		      pedwarn (input_location, 0,
-                               "declaration of %q#D with C language linkage",
-			       x);
-		      pedwarn (DECL_SOURCE_LOCATION (previous), 0,
-                               "conflicts with previous declaration %q#D",
-			       previous);
-		      pedwarn (input_location, 0,
-                               "due to different exception specifications");
-		      return error_mark_node;
-		    }
-		  if (DECL_ASSEMBLER_NAME_SET_P (previous))
-		    SET_DECL_ASSEMBLER_NAME (x,
-					     DECL_ASSEMBLER_NAME (previous));
-		}
-	      else
-		{
-		  pedwarn (input_location, 0,
-			   "declaration of %q#D with C language linkage", x);
-		  pedwarn (DECL_SOURCE_LOCATION (previous), 0,
-			   "conflicts with previous declaration %q#D",
-			   previous);
-		}
-	    }
-	}
+  return entry;
+}
 
-      check_template_shadow (x);
+/* Apply PROC -- with DATA -- to all entries in TABLE.  */
 
-      /* If this is a function conjured up by the back end, massage it
-	 so it looks friendly.  */
-      if (DECL_NON_THUNK_FUNCTION_P (x) && ! DECL_LANG_SPECIFIC (x))
-	{
-	  retrofit_lang_decl (x);
-	  SET_DECL_LANGUAGE (x, lang_c);
-	}
+void
+binding_table_foreach (binding_table table, bt_foreach_proc proc, void *data)
+{
+  size_t chain_count;
+  size_t i;
 
-      t = x;
-      if (DECL_NON_THUNK_FUNCTION_P (x) && ! DECL_FUNCTION_MEMBER_P (x))
-	{
-	  t = push_overloaded_decl (x, PUSH_LOCAL, is_friend);
-	  if (!namespace_bindings_p ())
-	    /* We do not need to create a binding for this name;
-	       push_overloaded_decl will have already done so if
-	       necessary.  */
-	    need_new_binding = 0;
-	}
-      else if (DECL_FUNCTION_TEMPLATE_P (x) && DECL_NAMESPACE_SCOPE_P (x))
-	{
-	  t = push_overloaded_decl (x, PUSH_GLOBAL, is_friend);
-	  if (t == x)
-	    add_decl_to_level (x, NAMESPACE_LEVEL (CP_DECL_CONTEXT (t)));
-	}
+  if (!table)
+    return;
 
-      if (DECL_DECLARES_FUNCTION_P (t))
-	{
-	  check_default_args (t);
+  chain_count = table->chain_count;
+  for (i = 0; i < chain_count; ++i)
+    {
+      binding_entry entry = table->chain[i];
+      for (; entry != NULL; entry = entry->chain)
+	proc (entry, data);
+    }
+}
+
+#ifndef ENABLE_SCOPE_CHECKING
+#  define ENABLE_SCOPE_CHECKING 0
+#else
+#  define ENABLE_SCOPE_CHECKING 1
+#endif
 
-	  if (is_friend && t == x && !flag_friend_injection)
-	    {
-	      /* This is a new friend declaration of a function or a
-		 function template, so hide it from ordinary function
-		 lookup.  */
-	      DECL_ANTICIPATED (t) = 1;
-	      DECL_HIDDEN_FRIEND_P (t) = 1;
-	    }
-	}
+/* A free list of "cxx_binding"s, connected by their PREVIOUS.  */
 
-      if (t != x || DECL_FUNCTION_TEMPLATE_P (t))
-	return t;
+static GTY((deletable)) cxx_binding *free_bindings;
 
-      /* If declaring a type as a typedef, copy the type (unless we're
-	 at line 0), and install this TYPE_DECL as the new type's typedef
-	 name.  See the extensive comment of set_underlying_type ().  */
-      if (TREE_CODE (x) == TYPE_DECL)
-	{
-	  tree type = TREE_TYPE (x);
+/* Initialize VALUE and TYPE field for BINDING, and set the PREVIOUS
+   field to NULL.  */
 
-	  if (DECL_IS_BUILTIN (x)
-	      || (TREE_TYPE (x) != error_mark_node
-		  && TYPE_NAME (type) != x
-		  /* We don't want to copy the type when all we're
-		     doing is making a TYPE_DECL for the purposes of
-		     inlining.  */
-		  && (!TYPE_NAME (type)
-		      || TYPE_NAME (type) != DECL_ABSTRACT_ORIGIN (x))))
-	    set_underlying_type (x);
+static inline void
+cxx_binding_init (cxx_binding *binding, tree value, tree type)
+{
+  binding->value = value;
+  binding->type = type;
+  binding->previous = NULL;
+}
 
-	  if (type != error_mark_node
-	      && TYPE_IDENTIFIER (type))
-	    set_identifier_type_value (DECL_NAME (x), x);
+/* (GC)-allocate a binding object with VALUE and TYPE member initialized.  */
 
-	  /* If this is a locally defined typedef in a function that
-	     is not a template instantation, record it to implement
-	     -Wunused-local-typedefs.  */
-	  if (!instantiating_current_function_p ())
-	    record_locally_defined_typedef (x);
-	}
+static cxx_binding *
+cxx_binding_make (tree value, tree type)
+{
+  cxx_binding *binding;
+  if (free_bindings)
+    {
+      binding = free_bindings;
+      free_bindings = binding->previous;
+    }
+  else
+    binding = ggc_alloc<cxx_binding> ();
 
-      /* Multiple external decls of the same identifier ought to match.
+  cxx_binding_init (binding, value, type);
 
-	 We get warnings about inline functions where they are defined.
-	 We get warnings about other functions from push_overloaded_decl.
+  return binding;
+}
 
-	 Avoid duplicate warnings where they are used.  */
-      if (TREE_PUBLIC (x) && TREE_CODE (x) != FUNCTION_DECL)
-	{
-	  tree decl;
+/* Put BINDING back on the free list.  */
 
-	  decl = IDENTIFIER_NAMESPACE_VALUE (name);
-	  if (decl && TREE_CODE (decl) == OVERLOAD)
-	    decl = OVL_FUNCTION (decl);
+static inline void
+cxx_binding_free (cxx_binding *binding)
+{
+  binding->scope = NULL;
+  binding->previous = free_bindings;
+  free_bindings = binding;
+}
 
-	  if (decl && decl != error_mark_node
-	      && (DECL_EXTERNAL (decl) || TREE_PUBLIC (decl))
-	      /* If different sort of thing, we already gave an error.  */
-	      && TREE_CODE (decl) == TREE_CODE (x)
-	      && !comptypes (TREE_TYPE (x), TREE_TYPE (decl),
-			     COMPARE_REDECLARATION))
-	    {
-	      if (permerror (input_location, "type mismatch with previous "
-			     "external decl of %q#D", x))
-		inform (DECL_SOURCE_LOCATION (decl),
-			"previous external decl of %q#D", decl);
-	    }
-	}
+/* Create a new binding for NAME (with the indicated VALUE and TYPE
+   bindings) in the class scope indicated by SCOPE.  */
 
-      /* This name is new in its binding level.
-	 Install the new declaration and return it.  */
-      if (namespace_bindings_p ())
-	{
-	  /* Install a global value.  */
+static cxx_binding *
+new_class_binding (tree name, tree value, tree type, cp_binding_level *scope)
+{
+  cp_class_binding cb = {cxx_binding_make (value, type), name};
+  cxx_binding *binding = cb.base;
+  vec_safe_push (scope->class_shadowed, cb);
+  binding->scope = scope;
+  return binding;
+}
 
-	  /* If the first global decl has external linkage,
-	     warn if we later see static one.  */
-	  if (IDENTIFIER_GLOBAL_VALUE (name) == NULL_TREE && TREE_PUBLIC (x))
-	    TREE_PUBLIC (name) = 1;
+/* Make DECL the innermost binding for ID.  The LEVEL is the binding
+   level at which this declaration is being bound.  */
 
-	  /* Bind the name for the entity.  */
-	  if (!(TREE_CODE (x) == TYPE_DECL && DECL_ARTIFICIAL (x)
-		&& t != NULL_TREE)
-	      && (TREE_CODE (x) == TYPE_DECL
-		  || VAR_P (x)
-		  || TREE_CODE (x) == NAMESPACE_DECL
-		  || TREE_CODE (x) == CONST_DECL
-		  || TREE_CODE (x) == TEMPLATE_DECL))
-	    SET_IDENTIFIER_NAMESPACE_VALUE (name, x);
+void
+push_binding (tree id, tree decl, cp_binding_level* level)
+{
+  cxx_binding *binding;
 
-	  /* If new decl is `static' and an `extern' was seen previously,
-	     warn about it.  */
-	  if (x != NULL_TREE && t != NULL_TREE && decls_match (x, t))
-	    warn_extern_redeclared_static (x, t);
-	}
-      else
-	{
-	  /* Here to install a non-global value.  */
-	  tree oldglobal = IDENTIFIER_NAMESPACE_VALUE (name);
-	  tree oldlocal = NULL_TREE;
-	  cp_binding_level *oldscope = NULL;
-	  cxx_binding *oldbinding = outer_binding (name, NULL, true);
-	  if (oldbinding)
-	    {
-	      oldlocal = oldbinding->value;
-	      oldscope = oldbinding->scope;
-	    }
+  if (level != class_binding_level)
+    {
+      binding = cxx_binding_make (decl, NULL_TREE);
+      binding->scope = level;
+    }
+  else
+    binding = new_class_binding (id, decl, /*type=*/NULL_TREE, level);
 
-	  if (need_new_binding)
-	    {
-	      push_local_binding (name, x, 0);
-	      /* Because push_local_binding will hook X on to the
-		 current_binding_level's name list, we don't want to
-		 do that again below.  */
-	      need_new_binding = 0;
-	    }
+  /* Now, fill in the binding information.  */
+  binding->previous = IDENTIFIER_BINDING (id);
+  INHERITED_VALUE_BINDING_P (binding) = 0;
+  LOCAL_BINDING_P (binding) = (level != class_binding_level);
 
-	  /* If this is a TYPE_DECL, push it into the type value slot.  */
-	  if (TREE_CODE (x) == TYPE_DECL)
-	    set_identifier_type_value (name, x);
-
-	  /* Clear out any TYPE_DECL shadowed by a namespace so that
-	     we won't think this is a type.  The C struct hack doesn't
-	     go through namespaces.  */
-	  if (TREE_CODE (x) == NAMESPACE_DECL)
-	    set_identifier_type_value (name, NULL_TREE);
-
-	  if (oldlocal)
-	    {
-	      tree d = oldlocal;
-
-	      while (oldlocal
-		     && VAR_P (oldlocal)
-		     && DECL_DEAD_FOR_LOCAL (oldlocal))
-		oldlocal = DECL_SHADOWED_FOR_VAR (oldlocal);
-
-	      if (oldlocal == NULL_TREE)
-		oldlocal = IDENTIFIER_NAMESPACE_VALUE (DECL_NAME (d));
-	    }
-
-	  /* If this is an extern function declaration, see if we
-	     have a global definition or declaration for the function.  */
-	  if (oldlocal == NULL_TREE
-	      && DECL_EXTERNAL (x)
-	      && oldglobal != NULL_TREE
-	      && TREE_CODE (x) == FUNCTION_DECL
-	      && TREE_CODE (oldglobal) == FUNCTION_DECL)
-	    {
-	      /* We have one.  Their types must agree.  */
-	      if (decls_match (x, oldglobal))
-		/* OK */;
-	      else
-		{
-		  warning (0, "extern declaration of %q#D doesn%'t match", x);
-		  warning_at (DECL_SOURCE_LOCATION (oldglobal), 0,
-			      "global declaration %q#D", oldglobal);
-		}
-	    }
-	  /* If we have a local external declaration,
-	     and no file-scope declaration has yet been seen,
-	     then if we later have a file-scope decl it must not be static.  */
-	  if (oldlocal == NULL_TREE
-	      && oldglobal == NULL_TREE
-	      && DECL_EXTERNAL (x)
-	      && TREE_PUBLIC (x))
-	    TREE_PUBLIC (name) = 1;
-
-	  /* Don't complain about the parms we push and then pop
-	     while tentatively parsing a function declarator.  */
-	  if (TREE_CODE (x) == PARM_DECL && DECL_CONTEXT (x) == NULL_TREE)
-	    /* Ignore.  */;
-
-	  /* Warn if shadowing an argument at the top level of the body.  */
-	  else if (oldlocal != NULL_TREE && !DECL_EXTERNAL (x)
-		   /* Inline decls shadow nothing.  */
-		   && !DECL_FROM_INLINE (x)
-		   && (TREE_CODE (oldlocal) == PARM_DECL
-		       || VAR_P (oldlocal)
-                       /* If the old decl is a type decl, only warn if the
-                          old decl is an explicit typedef or if both the old
-                          and new decls are type decls.  */
-                       || (TREE_CODE (oldlocal) == TYPE_DECL
-                           && (!DECL_ARTIFICIAL (oldlocal)
-                               || TREE_CODE (x) == TYPE_DECL)))
-                   /* Don't check for internally generated vars unless
-                      it's an implicit typedef (see create_implicit_typedef
-                      in decl.c) or anonymous union variable.  */
-		   && (!DECL_ARTIFICIAL (x)
-		       || DECL_IMPLICIT_TYPEDEF_P (x)
-		       || (VAR_P (x) && DECL_ANON_UNION_VAR_P (x))))
-	    {
-	      bool nowarn = false;
-
-	      /* Don't complain if it's from an enclosing function.  */
-	      if (DECL_CONTEXT (oldlocal) == current_function_decl
-		  && TREE_CODE (x) != PARM_DECL
-		  && TREE_CODE (oldlocal) == PARM_DECL)
-		{
-		  /* Go to where the parms should be and see if we find
-		     them there.  */
-		  cp_binding_level *b = current_binding_level->level_chain;
-
-		  if (FUNCTION_NEEDS_BODY_BLOCK (current_function_decl))
-		    /* Skip the ctor/dtor cleanup level.  */
-		    b = b->level_chain;
-
-		  /* ARM $8.3 */
-		  if (b->kind == sk_function_parms)
-		    {
-		      error ("declaration of %q#D shadows a parameter", x);
-		      nowarn = true;
-		    }
-		}
-
-	      /* The local structure or class can't use parameters of
-		 the containing function anyway.  */
-	      if (DECL_CONTEXT (oldlocal) != current_function_decl)
-		{
-		  cp_binding_level *scope = current_binding_level;
-		  tree context = DECL_CONTEXT (oldlocal);
-		  for (; scope; scope = scope->level_chain)
-		   {
-		     if (scope->kind == sk_function_parms
-			 && scope->this_entity == context)
-		      break;
-		     if (scope->kind == sk_class
-			 && !LAMBDA_TYPE_P (scope->this_entity))
-		       {
-			 nowarn = true;
-			 break;
-		       }
-		   }
-		}
-	      /* Error if redeclaring a local declared in a
-		 init-statement or in the condition of an if or
-		 switch statement when the new declaration is in the
-		 outermost block of the controlled statement.
-		 Redeclaring a variable from a for or while condition is
-		 detected elsewhere.  */
-	      else if (VAR_P (oldlocal)
-		       && oldscope == current_binding_level->level_chain
-		       && (oldscope->kind == sk_cond
-			   || oldscope->kind == sk_for))
-		{
-		  error ("redeclaration of %q#D", x);
-		  inform (DECL_SOURCE_LOCATION (oldlocal),
-			  "%q#D previously declared here", oldlocal);
-		  nowarn = true;
-		}
-	      /* C++11:
-		 3.3.3/3:  The name declared in an exception-declaration (...)
-		 shall not be redeclared in the outermost block of the handler.
-		 3.3.3/2:  A parameter name shall not be redeclared (...) in
-		 the outermost block of any handler associated with a
-		 function-try-block.
-		 3.4.1/15: The function parameter names shall not be redeclared
-		 in the exception-declaration nor in the outermost block of a
-		 handler for the function-try-block.  */
-	      else if ((VAR_P (oldlocal)
-			&& oldscope == current_binding_level->level_chain
-			&& oldscope->kind == sk_catch)
-		       || (TREE_CODE (oldlocal) == PARM_DECL
-			   && (current_binding_level->kind == sk_catch
-			       || (current_binding_level->level_chain->kind
-				   == sk_catch))
-			   && in_function_try_handler))
-		{
-		  if (permerror (input_location, "redeclaration of %q#D", x))
-		    inform (DECL_SOURCE_LOCATION (oldlocal),
-			    "%q#D previously declared here", oldlocal);
-		  nowarn = true;
-		}
-
-	      if ((warn_shadow
-		   || warn_shadow_local
-		   || warn_shadow_compatible_local)
-		  && !nowarn)
-		{
-		  bool warned;
-		  enum opt_code warning_code;
-		  /* If '-Wshadow=compatible-local' is specified without other
-		     -Wshadow= flags, we will warn only when the type of the
-		     shadowing variable (i.e. x) can be converted to that of
-		     the shadowed parameter (oldlocal). The reason why we only
-		     check if x's type can be converted to oldlocal's type
-		     (but not the other way around) is because when users
-		     accidentally shadow a parameter, more than often they
-		     would use the variable thinking (mistakenly) it's still
-		     the parameter. It would be rare that users would use the
-		     variable in the place that expects the parameter but
-		     thinking it's a new decl.  */
-		  if (warn_shadow)
-		    warning_code = OPT_Wshadow;
-		  else if (can_convert (TREE_TYPE (oldlocal), TREE_TYPE (x),
-					tf_none))
-		    warning_code = OPT_Wshadow_compatible_local;
-		  else
-		    warning_code = OPT_Wshadow_local;
-
-		  if (TREE_CODE (oldlocal) == PARM_DECL)
-		    warned = warning_at (input_location, warning_code,
-				"declaration of %q#D shadows a parameter", x);
-		  else if (is_capture_proxy (oldlocal))
-		    warned = warning_at (input_location, warning_code,
-				"declaration of %qD shadows a lambda capture",
-				x);
-		  else
-		    warned = warning_at (input_location, warning_code,
-				"declaration of %qD shadows a previous local",
-				x);
-
-		  if (warned)
-		    inform (DECL_SOURCE_LOCATION (oldlocal),
-			    "shadowed declaration is here");
-		}
-	    }
-
-	  /* Maybe warn if shadowing something else.  */
-	  else if (warn_shadow && !DECL_EXTERNAL (x)
-                   /* No shadow warnings for internally generated vars unless
-                      it's an implicit typedef (see create_implicit_typedef
-                      in decl.c).  */
-                   && (! DECL_ARTIFICIAL (x) || DECL_IMPLICIT_TYPEDEF_P (x))
-                   /* No shadow warnings for vars made for inlining.  */
-                   && ! DECL_FROM_INLINE (x))
-	    {
-	      tree member;
-
-	      if (nonlambda_method_basetype ())
-		member = lookup_member (current_nonlambda_class_type (),
-					name,
-					/*protect=*/0,
-					/*want_type=*/false,
-					tf_warning_or_error);
-	      else
-		member = NULL_TREE;
-
-	      if (member && !TREE_STATIC (member))
-		{
-		  if (BASELINK_P (member))
-		    member = BASELINK_FUNCTIONS (member);
-		  member = OVL_CURRENT (member);
-	
-		  /* Do not warn if a variable shadows a function, unless
-		     the variable is a function or a pointer-to-function.  */
-		  if (TREE_CODE (member) != FUNCTION_DECL
-		      || TREE_CODE (x) == FUNCTION_DECL
-		      || TYPE_PTRFN_P (TREE_TYPE (x))
-		      || TYPE_PTRMEMFUNC_P (TREE_TYPE (x)))
-		    {
-		      if (warning_at (input_location, OPT_Wshadow,
-				      "declaration of %qD shadows a member of %qT",
-				      x, current_nonlambda_class_type ())
-			  && DECL_P (member))
-			inform (DECL_SOURCE_LOCATION (member),
-				"shadowed declaration is here");
-		    }
-		}
-	      else if (oldglobal != NULL_TREE
-		       && (VAR_P (oldglobal)
-                           /* If the old decl is a type decl, only warn if the
-                              old decl is an explicit typedef or if both the
-                              old and new decls are type decls.  */
-                           || (TREE_CODE (oldglobal) == TYPE_DECL
-                               && (!DECL_ARTIFICIAL (oldglobal)
-                                   || TREE_CODE (x) == TYPE_DECL)))
-		       && !instantiating_current_function_p ())
-		/* XXX shadow warnings in outer-more namespaces */
-		{
-		  if (warning_at (input_location, OPT_Wshadow,
-				  "declaration of %qD shadows a "
-				  "global declaration", x))
-		    inform (DECL_SOURCE_LOCATION (oldglobal),
-			    "shadowed declaration is here");
-		}
-	    }
-	}
-
-      if (VAR_P (x))
-	maybe_register_incomplete_var (x);
-    }
-
-  if (need_new_binding)
-    add_decl_to_level (x,
-		       DECL_NAMESPACE_SCOPE_P (x)
-		       ? NAMESPACE_LEVEL (CP_DECL_CONTEXT (x))
-		       : current_binding_level);
-
-  return x;
+  /* And put it on the front of the list of bindings for ID.  */
+  IDENTIFIER_BINDING (id) = binding;
 }
 
-/* Wrapper for pushdecl_maybe_friend_1.  */
+/* Remove the binding for DECL which should be the innermost binding
+   for ID.  */
 
-tree
-pushdecl_maybe_friend (tree x, bool is_friend)
+void
+pop_binding (tree id, tree decl)
 {
-  tree ret;
-  bool subtime = timevar_cond_start (TV_NAME_LOOKUP);
-  ret = pushdecl_maybe_friend_1 (x, is_friend);
-  timevar_cond_stop (TV_NAME_LOOKUP, subtime);
-  return ret;
-}
-
-/* Record a decl-node X as belonging to the current lexical scope.  */
+  cxx_binding *binding;
 
-tree
-pushdecl (tree x)
-{
-  return pushdecl_maybe_friend (x, false);
-}
+  if (id == NULL_TREE)
+    /* It's easiest to write the loops that call this function without
+       checking whether or not the entities involved have names.  We
+       get here for such an entity.  */
+    return;
 
-/* Enter DECL into the symbol table, if that's appropriate.  Returns
-   DECL, or a modified version thereof.  */
+  /* Get the innermost binding for ID.  */
+  binding = IDENTIFIER_BINDING (id);
 
-tree
-maybe_push_decl (tree decl)
-{
-  tree type = TREE_TYPE (decl);
+  /* The name should be bound.  */
+  gcc_assert (binding != NULL);
 
-  /* Add this decl to the current binding level, but not if it comes
-     from another scope, e.g. a static member variable.  TEM may equal
-     DECL or it may be a previous decl of the same name.  */
-  if (decl == error_mark_node
-      || (TREE_CODE (decl) != PARM_DECL
-	  && DECL_CONTEXT (decl) != NULL_TREE
-	  /* Definitions of namespace members outside their namespace are
-	     possible.  */
-	  && !DECL_NAMESPACE_SCOPE_P (decl))
-      || (TREE_CODE (decl) == TEMPLATE_DECL && !namespace_bindings_p ())
-      || type == unknown_type_node
-      /* The declaration of a template specialization does not affect
-	 the functions available for overload resolution, so we do not
-	 call pushdecl.  */
-      || (TREE_CODE (decl) == FUNCTION_DECL
-	  && DECL_TEMPLATE_SPECIALIZATION (decl)))
-    return decl;
+  /* The DECL will be either the ordinary binding or the type
+     binding for this identifier.  Remove that binding.  */
+  if (binding->value == decl)
+    binding->value = NULL_TREE;
   else
-    return pushdecl (decl);
-}
-
-/* Bind DECL to ID in the current_binding_level, assumed to be a local
-   binding level.  If PUSH_USING is set in FLAGS, we know that DECL
-   doesn't really belong to this binding level, that it got here
-   through a using-declaration.  */
-
-void
-push_local_binding (tree id, tree decl, int flags)
-{
-  cp_binding_level *b;
-
-  /* Skip over any local classes.  This makes sense if we call
-     push_local_binding with a friend decl of a local class.  */
-  b = innermost_nonclass_level ();
+    {
+      gcc_assert (binding->type == decl);
+      binding->type = NULL_TREE;
+    }
 
-  if (lookup_name_innermost_nonclass_level (id))
+  if (!binding->value && !binding->type)
     {
-      /* Supplement the existing binding.  */
-      if (!supplement_binding (IDENTIFIER_BINDING (id), decl))
-	/* It didn't work.  Something else must be bound at this
-	   level.  Do not add DECL to the list of things to pop
-	   later.  */
-	return;
+      /* We're completely done with the innermost binding for this
+	 identifier.  Unhook it from the list of bindings.  */
+      IDENTIFIER_BINDING (id) = binding->previous;
+
+      /* Add it to the free list.  */
+      cxx_binding_free (binding);
     }
-  else
-    /* Create a new binding.  */
-    push_binding (id, decl, b);
+}
 
-  if (TREE_CODE (decl) == OVERLOAD || (flags & PUSH_USING))
-    /* We must put the OVERLOAD into a TREE_LIST since the
-       TREE_CHAIN of an OVERLOAD is already used.  Similarly for
-       decls that got here through a using-declaration.  */
-    decl = build_tree_list (NULL_TREE, decl);
+/* Remove the bindings for the decls of the current level and leave
+   the current scope.  */
 
-  /* And put DECL on the list of things declared by the current
-     binding level.  */
-  add_decl_to_level (decl, b);
+void
+pop_bindings_and_leave_scope (void)
+{
+  for (tree t = getdecls (); t; t = DECL_CHAIN (t))
+    pop_binding (DECL_NAME (t), t);
+  leave_scope ();
 }
 
-/* Check to see whether or not DECL is a variable that would have been
-   in scope under the ARM, but is not in scope under the ANSI/ISO
-   standard.  If so, issue an error message.  If name lookup would
-   work in both cases, but return a different result, this function
-   returns the result of ANSI/ISO lookup.  Otherwise, it returns
-   DECL.  */
+/* Strip non dependent using declarations. If DECL is dependent,
+   surreptitiously create a typename_type and return it.  */
 
 tree
-check_for_out_of_scope_variable (tree decl)
+strip_using_decl (tree decl)
 {
-  tree shadowed;
+  if (decl == NULL_TREE)
+    return NULL_TREE;
 
-  /* We only care about out of scope variables.  */
-  if (!(VAR_P (decl) && DECL_DEAD_FOR_LOCAL (decl)))
-    return decl;
+  while (TREE_CODE (decl) == USING_DECL && !DECL_DEPENDENT_P (decl))
+    decl = USING_DECL_DECLS (decl);
 
-  shadowed = DECL_HAS_SHADOWED_FOR_VAR_P (decl)
-    ? DECL_SHADOWED_FOR_VAR (decl) : NULL_TREE ;
-  while (shadowed != NULL_TREE && VAR_P (shadowed)
-	 && DECL_DEAD_FOR_LOCAL (shadowed))
-    shadowed = DECL_HAS_SHADOWED_FOR_VAR_P (shadowed)
-      ? DECL_SHADOWED_FOR_VAR (shadowed) : NULL_TREE;
-  if (!shadowed)
-    shadowed = IDENTIFIER_NAMESPACE_VALUE (DECL_NAME (decl));
-  if (shadowed)
+  if (TREE_CODE (decl) == USING_DECL && DECL_DEPENDENT_P (decl)
+      && USING_DECL_TYPENAME_P (decl))
     {
-      if (!DECL_ERROR_REPORTED (decl))
-	{
-	  warning (0, "name lookup of %qD changed", DECL_NAME (decl));
-	  warning_at (DECL_SOURCE_LOCATION (shadowed), 0,
-		      "  matches this %qD under ISO standard rules",
-		      shadowed);
-	  warning_at (DECL_SOURCE_LOCATION (decl), 0,
-		      "  matches this %qD under old rules", decl);
-	  DECL_ERROR_REPORTED (decl) = 1;
-	}
-      return shadowed;
+      /* We have found a type introduced by a using
+	 declaration at class scope that refers to a dependent
+	 type.
+	     
+	 using typename :: [opt] nested-name-specifier unqualified-id ;
+      */
+      decl = make_typename_type (TREE_TYPE (decl),
+				 DECL_NAME (decl),
+				 typename_type, tf_error);
+      if (decl != error_mark_node)
+	decl = TYPE_NAME (decl);
     }
 
-  /* If we have already complained about this declaration, there's no
-     need to do it again.  */
-  if (DECL_ERROR_REPORTED (decl))
-    return decl;
+  return decl;
+}
 
-  DECL_ERROR_REPORTED (decl) = 1;
+/* BINDING records an existing declaration for a name in the current scope.
+   But, DECL is another declaration for that same identifier in the
+   same scope.  This is the `struct stat' hack whereby a non-typedef
+   class name or enum-name can be bound at the same level as some other
+   kind of entity.
+   3.3.7/1
 
-  if (TREE_TYPE (decl) == error_mark_node)
-    return decl;
+     A class name (9.1) or enumeration name (7.2) can be hidden by the
+     name of an object, function, or enumerator declared in the same scope.
+     If a class or enumeration name and an object, function, or enumerator
+     are declared in the same scope (in any order) with the same name, the
+     class or enumeration name is hidden wherever the object, function, or
+     enumerator name is visible.
 
-  if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (TREE_TYPE (decl)))
-    {
-      error ("name lookup of %qD changed for ISO %<for%> scoping",
-	     DECL_NAME (decl));
-      error ("  cannot use obsolete binding at %q+D because "
-	     "it has a destructor", decl);
-      return error_mark_node;
-    }
-  else
+   It's the responsibility of the caller to check that
+   inserting this name is valid here.  Returns nonzero if the new binding
+   was successful.  */
+
+static bool
+supplement_binding_1 (cxx_binding *binding, tree decl)
+{
+  tree bval = binding->value;
+  bool ok = true;
+  tree target_bval = strip_using_decl (bval);
+  tree target_decl = strip_using_decl (decl);
+
+  if (TREE_CODE (target_decl) == TYPE_DECL && DECL_ARTIFICIAL (target_decl)
+      && target_decl != target_bval
+      && (TREE_CODE (target_bval) != TYPE_DECL
+	  /* We allow pushing an enum multiple times in a class
+	     template in order to handle late matching of underlying
+	     type on an opaque-enum-declaration followed by an
+	     enum-specifier.  */
+	  || (processing_template_decl
+	      && TREE_CODE (TREE_TYPE (target_decl)) == ENUMERAL_TYPE
+	      && TREE_CODE (TREE_TYPE (target_bval)) == ENUMERAL_TYPE
+	      && (dependent_type_p (ENUM_UNDERLYING_TYPE
+				    (TREE_TYPE (target_decl)))
+		  || dependent_type_p (ENUM_UNDERLYING_TYPE
+				       (TREE_TYPE (target_bval)))))))
+    /* The new name is the type name.  */
+    binding->type = decl;
+  else if (/* TARGET_BVAL is null when push_class_level_binding moves
+	      an inherited type-binding out of the way to make room
+	      for a new value binding.  */
+	   !target_bval
+	   /* TARGET_BVAL is error_mark_node when TARGET_DECL's name
+	      has been used in a non-class scope prior declaration.
+	      In that case, we should have already issued a
+	      diagnostic; for graceful error recovery purpose, pretend
+	      this was the intended declaration for that name.  */
+	   || target_bval == error_mark_node
+	   /* If TARGET_BVAL is anticipated but has not yet been
+	      declared, pretend it is not there at all.  */
+	   || (TREE_CODE (target_bval) == FUNCTION_DECL
+	       && DECL_ANTICIPATED (target_bval)
+	       && !DECL_HIDDEN_FRIEND_P (target_bval)))
+    binding->value = decl;
+  else if (TREE_CODE (target_bval) == TYPE_DECL
+	   && DECL_ARTIFICIAL (target_bval)
+	   && target_decl != target_bval
+	   && (TREE_CODE (target_decl) != TYPE_DECL
+	       || same_type_p (TREE_TYPE (target_decl),
+			       TREE_TYPE (target_bval))))
     {
-      permerror (input_location, "name lookup of %qD changed for ISO %<for%> scoping",
-	         DECL_NAME (decl));
-      if (flag_permissive)
-        permerror (DECL_SOURCE_LOCATION (decl),
-		   "  using obsolete binding at %qD", decl);
-      else
-	{
-	  static bool hint;
-	  if (!hint)
-	    {
-	      inform (input_location, "(if you use %<-fpermissive%> G++ will accept your code)");
-	      hint = true;
-	    }
-	}
+      /* The old binding was a type name.  It was placed in
+	 VALUE field because it was thought, at the point it was
+	 declared, to be the only entity with such a name.  Move the
+	 type name into the type slot; it is now hidden by the new
+	 binding.  */
+      binding->type = bval;
+      binding->value = decl;
+      binding->value_is_inherited = false;
     }
+  else if (TREE_CODE (target_bval) == TYPE_DECL
+	   && TREE_CODE (target_decl) == TYPE_DECL
+	   && DECL_NAME (target_decl) == DECL_NAME (target_bval)
+	   && binding->scope->kind != sk_class
+	   && (same_type_p (TREE_TYPE (target_decl), TREE_TYPE (target_bval))
+	       /* If either type involves template parameters, we must
+		  wait until instantiation.  */
+	       || uses_template_parms (TREE_TYPE (target_decl))
+	       || uses_template_parms (TREE_TYPE (target_bval))))
+    /* We have two typedef-names, both naming the same type to have
+       the same name.  In general, this is OK because of:
 
-  return decl;
-}
-
-/* true means unconditionally make a BLOCK for the next level pushed.  */
+	 [dcl.typedef]
 
-static bool keep_next_level_flag;
+	 In a given scope, a typedef specifier can be used to redefine
+	 the name of any type declared in that scope to refer to the
+	 type to which it already refers.
 
-static int binding_depth = 0;
+       However, in class scopes, this rule does not apply due to the
+       stricter language in [class.mem] prohibiting redeclarations of
+       members.  */
+    ok = false;
+  /* There can be two block-scope declarations of the same variable,
+     so long as they are `extern' declarations.  However, there cannot
+     be two declarations of the same static data member:
 
-static void
-indent (int depth)
-{
-  int i;
+       [class.mem]
 
-  for (i = 0; i < depth * 2; i++)
-    putc (' ', stderr);
-}
+       A member shall not be declared twice in the
+       member-specification.  */
+  else if (VAR_P (target_decl)
+	   && VAR_P (target_bval)
+	   && DECL_EXTERNAL (target_decl) && DECL_EXTERNAL (target_bval)
+	   && !DECL_CLASS_SCOPE_P (target_decl))
+    {
+      duplicate_decls (decl, binding->value, /*newdecl_is_friend=*/false);
+      ok = false;
+    }
+  else if (TREE_CODE (decl) == NAMESPACE_DECL
+	   && TREE_CODE (bval) == NAMESPACE_DECL
+	   && DECL_NAMESPACE_ALIAS (decl)
+	   && DECL_NAMESPACE_ALIAS (bval)
+	   && ORIGINAL_NAMESPACE (bval) == ORIGINAL_NAMESPACE (decl))
+    /* [namespace.alias]
 
-/* Return a string describing the kind of SCOPE we have.  */
-static const char *
-cp_binding_level_descriptor (cp_binding_level *scope)
-{
-  /* The order of this table must match the "scope_kind"
-     enumerators.  */
-  static const char* scope_kind_names[] = {
-    "block-scope",
-    "cleanup-scope",
-    "try-scope",
-    "catch-scope",
-    "for-scope",
-    "function-parameter-scope",
-    "class-scope",
-    "namespace-scope",
-    "template-parameter-scope",
-    "template-explicit-spec-scope"
-  };
-  const scope_kind kind = scope->explicit_spec_p
-    ? sk_template_spec : scope->kind;
+      In a declarative region, a namespace-alias-definition can be
+      used to redefine a namespace-alias declared in that declarative
+      region to refer only to the namespace to which it already
+      refers.  */
+    ok = false;
+  else if (maybe_remove_implicit_alias (bval))
+    {
+      /* There was a mangling compatibility alias using this mangled name,
+	 but now we have a real decl that wants to use it instead.  */
+      binding->value = decl;
+    }
+  else
+    {
+      if (!error_operand_p (bval))
+	diagnose_name_conflict (decl, bval);
+      ok = false;
+    }
 
-  return scope_kind_names[kind];
+  return ok;
 }
 
-/* Output a debugging information about SCOPE when performing
-   ACTION at LINE.  */
+/* Diagnose a name conflict between DECL and BVAL.  */
+
 static void
-cp_binding_level_debug (cp_binding_level *scope, int line, const char *action)
-{
-  const char *desc = cp_binding_level_descriptor (scope);
-  if (scope->this_entity)
-    verbatim ("%s %s(%E) %p %d\n", action, desc,
-	      scope->this_entity, (void *) scope, line);
+diagnose_name_conflict (tree decl, tree bval)
+{
+  if (TREE_CODE (decl) == TREE_CODE (bval)
+      && (TREE_CODE (decl) != TYPE_DECL
+	  || (DECL_ARTIFICIAL (decl) && DECL_ARTIFICIAL (bval))
+	  || (!DECL_ARTIFICIAL (decl) && !DECL_ARTIFICIAL (bval)))
+      && !is_overloaded_fn (decl))
+    error ("redeclaration of %q#D", decl);
   else
-    verbatim ("%s %s %p %d\n", action, desc, (void *) scope, line);
+    error ("%q#D conflicts with a previous declaration", decl);
+
+  inform (location_of (bval), "previous declaration %q#D", bval);
 }
 
-/* Return the estimated initial size of the hashtable of a NAMESPACE
-   scope.  */
+/* Wrapper for supplement_binding_1.  */
 
-static inline size_t
-namespace_scope_ht_size (tree ns)
+static bool
+supplement_binding (cxx_binding *binding, tree decl)
 {
-  tree name = DECL_NAME (ns);
-
-  return name == std_identifier
-    ? NAMESPACE_STD_HT_SIZE
-    : (name == global_scope_name
-       ? GLOBAL_SCOPE_HT_SIZE
-       : NAMESPACE_ORDINARY_HT_SIZE);
+  bool ret;
+  bool subtime = timevar_cond_start (TV_NAME_LOOKUP);
+  ret = supplement_binding_1 (binding, decl);
+  timevar_cond_stop (TV_NAME_LOOKUP, subtime);
+  return ret;
 }
 
-/* A chain of binding_level structures awaiting reuse.  */
-
-static GTY((deletable)) cp_binding_level *free_binding_level;
+/* Record a decl-node X as belonging to the current lexical scope.
+   Check for errors (such as an incompatible declaration for the same
+   name already seen in the same scope).  IS_FRIEND is true if X is
+   declared as a friend.
 
-/* Insert SCOPE as the innermost binding level.  */
+   Returns either X or an old decl for the same name.
+   If an old decl is returned, it may have been smashed
+   to agree with what X says.  */
 
-void
-push_binding_level (cp_binding_level *scope)
+static tree
+pushdecl_maybe_friend_1 (tree x, bool is_friend)
 {
-  /* Add it to the front of currently active scopes stack.  */
-  scope->level_chain = current_binding_level;
-  current_binding_level = scope;
-  keep_next_level_flag = false;
-
-  if (ENABLE_SCOPE_CHECKING)
-    {
-      scope->binding_depth = binding_depth;
-      indent (binding_depth);
-      cp_binding_level_debug (scope, LOCATION_LINE (input_location),
-			      "push");
-      binding_depth++;
-    }
-}
+  tree t;
+  tree name;
+  int need_new_binding;
 
-/* Create a new KIND scope and make it the top of the active scopes stack.
-   ENTITY is the scope of the associated C++ entity (namespace, class,
-   function, C++0x enumeration); it is NULL otherwise.  */
+  if (x == error_mark_node)
+    return error_mark_node;
 
-cp_binding_level *
-begin_scope (scope_kind kind, tree entity)
-{
-  cp_binding_level *scope;
+  need_new_binding = 1;
 
-  /* Reuse or create a struct for this binding level.  */
-  if (!ENABLE_SCOPE_CHECKING && free_binding_level)
+  if (DECL_TEMPLATE_PARM_P (x))
+    /* Template parameters have no context; they are not X::T even
+       when declared within a class or namespace.  */
+    ;
+  else
     {
-      scope = free_binding_level;
-      free_binding_level = scope->level_chain;
-      memset (scope, 0, sizeof (cp_binding_level));
+      if (current_function_decl && x != current_function_decl
+	  /* A local declaration for a function doesn't constitute
+	     nesting.  */
+	  && TREE_CODE (x) != FUNCTION_DECL
+	  /* A local declaration for an `extern' variable is in the
+	     scope of the current namespace, not the current
+	     function.  */
+	  && !(VAR_P (x) && DECL_EXTERNAL (x))
+	  /* When parsing the parameter list of a function declarator,
+	     don't set DECL_CONTEXT to an enclosing function.  When we
+	     push the PARM_DECLs in order to process the function body,
+	     current_binding_level->this_entity will be set.  */
+	  && !(TREE_CODE (x) == PARM_DECL
+	       && current_binding_level->kind == sk_function_parms
+	       && current_binding_level->this_entity == NULL)
+	  && !DECL_CONTEXT (x))
+	DECL_CONTEXT (x) = current_function_decl;
+
+      /* If this is the declaration for a namespace-scope function,
+	 but the declaration itself is in a local scope, mark the
+	 declaration.  */
+      if (TREE_CODE (x) == FUNCTION_DECL
+	  && DECL_NAMESPACE_SCOPE_P (x)
+	  && current_function_decl
+	  && x != current_function_decl)
+	DECL_LOCAL_FUNCTION_P (x) = 1;
     }
-  else
-    scope = ggc_cleared_alloc<cp_binding_level> ();
 
-  scope->this_entity = entity;
-  scope->more_cleanups_ok = true;
-  switch (kind)
+  name = DECL_NAME (x);
+  if (name)
     {
-    case sk_cleanup:
-      scope->keep = true;
-      break;
+      int different_binding_level = 0;
 
-    case sk_template_spec:
-      scope->explicit_spec_p = true;
-      kind = sk_template_parms;
-      /* Fall through.  */
-    case sk_template_parms:
-    case sk_block:
-    case sk_try:
-    case sk_catch:
-    case sk_for:
-    case sk_cond:
-    case sk_class:
-    case sk_scoped_enum:
-    case sk_function_parms:
-    case sk_transaction:
-    case sk_omp:
-      scope->keep = keep_next_level_flag;
-      break;
+      if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
+	name = TREE_OPERAND (name, 0);
 
-    case sk_namespace:
-      NAMESPACE_LEVEL (entity) = scope;
-      vec_alloc (scope->static_decls,
-		 (DECL_NAME (entity) == std_identifier
-		  || DECL_NAME (entity) == global_scope_name) ? 200 : 10);
-      break;
+      /* In case this decl was explicitly namespace-qualified, look it
+	 up in its namespace context.  */
+      if (DECL_NAMESPACE_SCOPE_P (x) && namespace_bindings_p ())
+	t = namespace_binding (name, DECL_CONTEXT (x));
+      else
+	t = lookup_name_innermost_nonclass_level (name);
 
-    default:
-      /* Should not happen.  */
-      gcc_unreachable ();
-      break;
-    }
-  scope->kind = kind;
+      /* [basic.link] If there is a visible declaration of an entity
+	 with linkage having the same name and type, ignoring entities
+	 declared outside the innermost enclosing namespace scope, the
+	 block scope declaration declares that same entity and
+	 receives the linkage of the previous declaration.  */
+      if (! t && current_function_decl && x != current_function_decl
+	  && VAR_OR_FUNCTION_DECL_P (x)
+	  && DECL_EXTERNAL (x))
+	{
+	  /* Look in block scope.  */
+	  t = innermost_non_namespace_value (name);
+	  /* Or in the innermost namespace.  */
+	  if (! t)
+	    t = namespace_binding (name, DECL_CONTEXT (x));
+	  /* Does it have linkage?  Note that if this isn't a DECL, it's an
+	     OVERLOAD, which is OK.  */
+	  if (t && DECL_P (t) && ! (TREE_STATIC (t) || DECL_EXTERNAL (t)))
+	    t = NULL_TREE;
+	  if (t)
+	    different_binding_level = 1;
+	}
 
-  push_binding_level (scope);
+      /* If we are declaring a function, and the result of name-lookup
+	 was an OVERLOAD, look for an overloaded instance that is
+	 actually the same as the function we are declaring.  (If
+	 there is one, we have to merge our declaration with the
+	 previous declaration.)  */
+      if (t && TREE_CODE (t) == OVERLOAD)
+	{
+	  tree match;
 
-  return scope;
-}
+	  if (TREE_CODE (x) == FUNCTION_DECL)
+	    for (match = t; match; match = OVL_NEXT (match))
+	      {
+		if (decls_match (OVL_CURRENT (match), x))
+		  break;
+	      }
+	  else
+	    /* Just choose one.  */
+	    match = t;
+
+	  if (match)
+	    t = OVL_CURRENT (match);
+	  else
+	    t = NULL_TREE;
+	}
+
+      if (t && t != error_mark_node)
+	{
+	  if (different_binding_level)
+	    {
+	      if (decls_match (x, t))
+		/* The standard only says that the local extern
+		   inherits linkage from the previous decl; in
+		   particular, default args are not shared.  Add
+		   the decl into a hash table to make sure only
+		   the previous decl in this case is seen by the
+		   middle end.  */
+		{
+		  struct cxx_int_tree_map *h;
+
+		  TREE_PUBLIC (x) = TREE_PUBLIC (t);
+
+		  if (cp_function_chain->extern_decl_map == NULL)
+		    cp_function_chain->extern_decl_map
+		      = hash_table<cxx_int_tree_map_hasher>::create_ggc (20);
+
+		  h = ggc_alloc<cxx_int_tree_map> ();
+		  h->uid = DECL_UID (x);
+		  h->to = t;
+		  cxx_int_tree_map **loc = cp_function_chain->extern_decl_map
+		    ->find_slot (h, INSERT);
+		  *loc = h;
+		}
+	    }
+	  else if (TREE_CODE (t) == PARM_DECL)
+	    {
+	      /* Check for duplicate params.  */
+	      tree d = duplicate_decls (x, t, is_friend);
+	      if (d)
+		return d;
+	    }
+	  else if ((DECL_EXTERN_C_FUNCTION_P (x)
+		    || DECL_FUNCTION_TEMPLATE_P (x))
+		   && is_overloaded_fn (t))
+	    /* Don't do anything just yet.  */;
+	  else if (t == wchar_decl_node)
+	    {
+	      if (! DECL_IN_SYSTEM_HEADER (x))
+		pedwarn (input_location, OPT_Wpedantic, "redeclaration of %<wchar_t%> as %qT",
+			 TREE_TYPE (x));
+	      
+	      /* Throw away the redeclaration.  */
+	      return t;
+	    }
+	  else
+	    {
+	      tree olddecl = duplicate_decls (x, t, is_friend);
+
+	      /* If the redeclaration failed, we can stop at this
+		 point.  */
+	      if (olddecl == error_mark_node)
+		return error_mark_node;
 
-/* We're about to leave current scope.  Pop the top of the stack of
-   currently active scopes.  Return the enclosing scope, now active.  */
+	      if (olddecl)
+		{
+		  if (TREE_CODE (t) == TYPE_DECL)
+		    SET_IDENTIFIER_TYPE_VALUE (name, TREE_TYPE (t));
 
-cp_binding_level *
-leave_scope (void)
-{
-  cp_binding_level *scope = current_binding_level;
+		  return t;
+		}
+	      else if (DECL_MAIN_P (x) && TREE_CODE (t) == FUNCTION_DECL)
+		{
+		  /* A redeclaration of main, but not a duplicate of the
+		     previous one.
 
-  if (scope->kind == sk_namespace && class_binding_level)
-    current_binding_level = class_binding_level;
+		     [basic.start.main]
 
-  /* We cannot leave a scope, if there are none left.  */
-  if (NAMESPACE_LEVEL (global_namespace))
-    gcc_assert (!global_scope_p (scope));
+		     This function shall not be overloaded.  */
+		  error ("invalid redeclaration of %q+D", t);
+		  error ("as %qD", x);
+		  /* We don't try to push this declaration since that
+		     causes a crash.  */
+		  return x;
+		}
+	    }
+	}
 
-  if (ENABLE_SCOPE_CHECKING)
-    {
-      indent (--binding_depth);
-      cp_binding_level_debug (scope, LOCATION_LINE (input_location),
-			      "leave");
-    }
+      /* If x has C linkage-specification, (extern "C"),
+	 lookup its binding, in case it's already bound to an object.
+	 The lookup is done in all namespaces.
+	 If we find an existing binding, make sure it has the same
+	 exception specification as x, otherwise, bail in error [7.5, 7.6].  */
+      if ((TREE_CODE (x) == FUNCTION_DECL)
+	  && DECL_EXTERN_C_P (x)
+          /* We should ignore declarations happening in system headers.  */
+	  && !DECL_ARTIFICIAL (x)
+	  && !DECL_IN_SYSTEM_HEADER (x))
+	{
+	  tree previous = lookup_extern_c_fun_in_all_ns (x);
+	  if (previous
+	      && !DECL_ARTIFICIAL (previous)
+              && !DECL_IN_SYSTEM_HEADER (previous)
+	      && DECL_CONTEXT (previous) != DECL_CONTEXT (x))
+	    {
+	      /* In case either x or previous is declared to throw an exception,
+	         make sure both exception specifications are equal.  */
+	      if (decls_match (x, previous))
+		{
+		  tree x_exception_spec = NULL_TREE;
+		  tree previous_exception_spec = NULL_TREE;
 
-  /* Move one nesting level up.  */
-  current_binding_level = scope->level_chain;
+		  x_exception_spec =
+				TYPE_RAISES_EXCEPTIONS (TREE_TYPE (x));
+		  previous_exception_spec =
+				TYPE_RAISES_EXCEPTIONS (TREE_TYPE (previous));
+		  if (!comp_except_specs (previous_exception_spec,
+					  x_exception_spec,
+					  ce_normal))
+		    {
+		      pedwarn (input_location, 0,
+                               "declaration of %q#D with C language linkage",
+			       x);
+		      pedwarn (DECL_SOURCE_LOCATION (previous), 0,
+                               "conflicts with previous declaration %q#D",
+			       previous);
+		      pedwarn (input_location, 0,
+                               "due to different exception specifications");
+		      return error_mark_node;
+		    }
+		  if (DECL_ASSEMBLER_NAME_SET_P (previous))
+		    SET_DECL_ASSEMBLER_NAME (x,
+					     DECL_ASSEMBLER_NAME (previous));
+		}
+	      else
+		{
+		  pedwarn (input_location, 0,
+			   "declaration of %q#D with C language linkage", x);
+		  pedwarn (DECL_SOURCE_LOCATION (previous), 0,
+			   "conflicts with previous declaration %q#D",
+			   previous);
+		}
+	    }
+	}
 
-  /* Namespace-scopes are left most probably temporarily, not
-     completely; they can be reopened later, e.g. in namespace-extension
-     or any name binding activity that requires us to resume a
-     namespace.  For classes, we cache some binding levels.  For other
-     scopes, we just make the structure available for reuse.  */
-  if (scope->kind != sk_namespace
-      && scope->kind != sk_class)
-    {
-      scope->level_chain = free_binding_level;
-      gcc_assert (!ENABLE_SCOPE_CHECKING
-		  || scope->binding_depth == binding_depth);
-      free_binding_level = scope;
-    }
+      check_template_shadow (x);
 
-  if (scope->kind == sk_class)
-    {
-      /* Reset DEFINING_CLASS_P to allow for reuse of a
-	 class-defining scope in a non-defining context.  */
-      scope->defining_class_p = 0;
+      /* If this is a function conjured up by the back end, massage it
+	 so it looks friendly.  */
+      if (DECL_NON_THUNK_FUNCTION_P (x) && ! DECL_LANG_SPECIFIC (x))
+	{
+	  retrofit_lang_decl (x);
+	  SET_DECL_LANGUAGE (x, lang_c);
+	}
 
-      /* Find the innermost enclosing class scope, and reset
-	 CLASS_BINDING_LEVEL appropriately.  */
-      class_binding_level = NULL;
-      for (scope = current_binding_level; scope; scope = scope->level_chain)
-	if (scope->kind == sk_class)
-	  {
-	    class_binding_level = scope;
-	    break;
-	  }
-    }
+      t = x;
+      if (DECL_NON_THUNK_FUNCTION_P (x) && ! DECL_FUNCTION_MEMBER_P (x))
+	{
+	  t = push_overloaded_decl (x, PUSH_LOCAL, is_friend);
+	  if (!namespace_bindings_p ())
+	    /* We do not need to create a binding for this name;
+	       push_overloaded_decl will have already done so if
+	       necessary.  */
+	    need_new_binding = 0;
+	}
+      else if (DECL_FUNCTION_TEMPLATE_P (x) && DECL_NAMESPACE_SCOPE_P (x))
+	{
+	  t = push_overloaded_decl (x, PUSH_GLOBAL, is_friend);
+	  if (t == x)
+	    add_decl_to_level (x, NAMESPACE_LEVEL (CP_DECL_CONTEXT (t)));
+	}
 
-  return current_binding_level;
-}
+      if (DECL_DECLARES_FUNCTION_P (t))
+	{
+	  check_default_args (t);
 
-static void
-resume_scope (cp_binding_level* b)
-{
-  /* Resuming binding levels is meant only for namespaces,
-     and those cannot nest into classes.  */
-  gcc_assert (!class_binding_level);
-  /* Also, resuming a non-directly nested namespace is a no-no.  */
-  gcc_assert (b->level_chain == current_binding_level);
-  current_binding_level = b;
-  if (ENABLE_SCOPE_CHECKING)
-    {
-      b->binding_depth = binding_depth;
-      indent (binding_depth);
-      cp_binding_level_debug (b, LOCATION_LINE (input_location), "resume");
-      binding_depth++;
-    }
-}
+	  if (is_friend && t == x && !flag_friend_injection)
+	    {
+	      /* This is a new friend declaration of a function or a
+		 function template, so hide it from ordinary function
+		 lookup.  */
+	      DECL_ANTICIPATED (t) = 1;
+	      DECL_HIDDEN_FRIEND_P (t) = 1;
+	    }
+	}
 
-/* Return the innermost binding level that is not for a class scope.  */
+      if (t != x || DECL_FUNCTION_TEMPLATE_P (t))
+	return t;
 
-static cp_binding_level *
-innermost_nonclass_level (void)
-{
-  cp_binding_level *b;
+      /* If declaring a type as a typedef, copy the type (unless we're
+	 at line 0), and install this TYPE_DECL as the new type's typedef
+	 name.  See the extensive comment of set_underlying_type ().  */
+      if (TREE_CODE (x) == TYPE_DECL)
+	{
+	  tree type = TREE_TYPE (x);
 
-  b = current_binding_level;
-  while (b->kind == sk_class)
-    b = b->level_chain;
+	  if (DECL_IS_BUILTIN (x)
+	      || (TREE_TYPE (x) != error_mark_node
+		  && TYPE_NAME (type) != x
+		  /* We don't want to copy the type when all we're
+		     doing is making a TYPE_DECL for the purposes of
+		     inlining.  */
+		  && (!TYPE_NAME (type)
+		      || TYPE_NAME (type) != DECL_ABSTRACT_ORIGIN (x))))
+	    set_underlying_type (x);
 
-  return b;
-}
+	  if (type != error_mark_node
+	      && TYPE_IDENTIFIER (type))
+	    set_identifier_type_value (DECL_NAME (x), x);
 
-/* We're defining an object of type TYPE.  If it needs a cleanup, but
-   we're not allowed to add any more objects with cleanups to the current
-   scope, create a new binding level.  */
+	  /* If this is a locally defined typedef in a function that
+	     is not a template instantation, record it to implement
+	     -Wunused-local-typedefs.  */
+	  if (!instantiating_current_function_p ())
+	    record_locally_defined_typedef (x);
+	}
 
-void
-maybe_push_cleanup_level (tree type)
-{
-  if (type != error_mark_node
-      && TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type)
-      && current_binding_level->more_cleanups_ok == 0)
-    {
-      begin_scope (sk_cleanup, NULL);
-      current_binding_level->statement_list = push_stmt_list ();
-    }
-}
+      /* Multiple external decls of the same identifier ought to match.
 
-/* Return true if we are in the global binding level.  */
+	 We get warnings about inline functions where they are defined.
+	 We get warnings about other functions from push_overloaded_decl.
 
-bool
-global_bindings_p (void)
-{
-  return global_scope_p (current_binding_level);
-}
+	 Avoid duplicate warnings where they are used.  */
+      if (TREE_PUBLIC (x) && TREE_CODE (x) != FUNCTION_DECL)
+	{
+	  tree decl;
 
-/* True if we are currently in a toplevel binding level.  This
-   means either the global binding level or a namespace in a toplevel
-   binding level.  Since there are no non-toplevel namespace levels,
-   this really means any namespace or template parameter level.  We
-   also include a class whose context is toplevel.  */
+	  decl = IDENTIFIER_NAMESPACE_VALUE (name);
+	  if (decl && TREE_CODE (decl) == OVERLOAD)
+	    decl = OVL_FUNCTION (decl);
 
-bool
-toplevel_bindings_p (void)
-{
-  cp_binding_level *b = innermost_nonclass_level ();
+	  if (decl && decl != error_mark_node
+	      && (DECL_EXTERNAL (decl) || TREE_PUBLIC (decl))
+	      /* If different sort of thing, we already gave an error.  */
+	      && TREE_CODE (decl) == TREE_CODE (x)
+	      && !comptypes (TREE_TYPE (x), TREE_TYPE (decl),
+			     COMPARE_REDECLARATION))
+	    {
+	      if (permerror (input_location, "type mismatch with previous "
+			     "external decl of %q#D", x))
+		inform (DECL_SOURCE_LOCATION (decl),
+			"previous external decl of %q#D", decl);
+	    }
+	}
 
-  return b->kind == sk_namespace || b->kind == sk_template_parms;
-}
+      /* This name is new in its binding level.
+	 Install the new declaration and return it.  */
+      if (namespace_bindings_p ())
+	{
+	  /* Install a global value.  */
 
-/* True if this is a namespace scope, or if we are defining a class
-   which is itself at namespace scope, or whose enclosing class is
-   such a class, etc.  */
+	  /* If the first global decl has external linkage,
+	     warn if we later see static one.  */
+	  if (IDENTIFIER_GLOBAL_VALUE (name) == NULL_TREE && TREE_PUBLIC (x))
+	    TREE_PUBLIC (name) = 1;
 
-bool
-namespace_bindings_p (void)
-{
-  cp_binding_level *b = innermost_nonclass_level ();
+	  /* Bind the name for the entity.  */
+	  if (!(TREE_CODE (x) == TYPE_DECL && DECL_ARTIFICIAL (x)
+		&& t != NULL_TREE)
+	      && (TREE_CODE (x) == TYPE_DECL
+		  || VAR_P (x)
+		  || TREE_CODE (x) == NAMESPACE_DECL
+		  || TREE_CODE (x) == CONST_DECL
+		  || TREE_CODE (x) == TEMPLATE_DECL))
+	    SET_IDENTIFIER_NAMESPACE_VALUE (name, x);
 
-  return b->kind == sk_namespace;
-}
+	  /* If new decl is `static' and an `extern' was seen previously,
+	     warn about it.  */
+	  if (x != NULL_TREE && t != NULL_TREE && decls_match (x, t))
+	    warn_extern_redeclared_static (x, t);
+	}
+      else
+	{
+	  /* Here to install a non-global value.  */
+	  tree oldglobal = IDENTIFIER_NAMESPACE_VALUE (name);
+	  tree oldlocal = NULL_TREE;
+	  cp_binding_level *oldscope = NULL;
+	  cxx_binding *oldbinding = outer_binding (name, NULL, true);
+	  if (oldbinding)
+	    {
+	      oldlocal = oldbinding->value;
+	      oldscope = oldbinding->scope;
+	    }
 
-/* True if the innermost non-class scope is a block scope.  */
+	  if (need_new_binding)
+	    {
+	      push_local_binding (name, x, 0);
+	      /* Because push_local_binding will hook X on to the
+		 current_binding_level's name list, we don't want to
+		 do that again below.  */
+	      need_new_binding = 0;
+	    }
 
-bool
-local_bindings_p (void)
-{
-  cp_binding_level *b = innermost_nonclass_level ();
-  return b->kind < sk_function_parms || b->kind == sk_omp;
-}
+	  /* If this is a TYPE_DECL, push it into the type value slot.  */
+	  if (TREE_CODE (x) == TYPE_DECL)
+	    set_identifier_type_value (name, x);
 
-/* True if the current level needs to have a BLOCK made.  */
+	  /* Clear out any TYPE_DECL shadowed by a namespace so that
+	     we won't think this is a type.  The C struct hack doesn't
+	     go through namespaces.  */
+	  if (TREE_CODE (x) == NAMESPACE_DECL)
+	    set_identifier_type_value (name, NULL_TREE);
 
-bool
-kept_level_p (void)
-{
-  return (current_binding_level->blocks != NULL_TREE
-	  || current_binding_level->keep
-	  || current_binding_level->kind == sk_cleanup
-	  || current_binding_level->names != NULL_TREE
-	  || current_binding_level->using_directives);
-}
+	  if (oldlocal)
+	    {
+	      tree d = oldlocal;
 
-/* Returns the kind of the innermost scope.  */
+	      while (oldlocal
+		     && VAR_P (oldlocal)
+		     && DECL_DEAD_FOR_LOCAL (oldlocal))
+		oldlocal = DECL_SHADOWED_FOR_VAR (oldlocal);
 
-scope_kind
-innermost_scope_kind (void)
-{
-  return current_binding_level->kind;
-}
+	      if (oldlocal == NULL_TREE)
+		oldlocal = IDENTIFIER_NAMESPACE_VALUE (DECL_NAME (d));
+	    }
 
-/* Returns true if this scope was created to store template parameters.  */
+	  /* If this is an extern function declaration, see if we
+	     have a global definition or declaration for the function.  */
+	  if (oldlocal == NULL_TREE
+	      && DECL_EXTERNAL (x)
+	      && oldglobal != NULL_TREE
+	      && TREE_CODE (x) == FUNCTION_DECL
+	      && TREE_CODE (oldglobal) == FUNCTION_DECL)
+	    {
+	      /* We have one.  Their types must agree.  */
+	      if (decls_match (x, oldglobal))
+		/* OK */;
+	      else
+		{
+		  warning (0, "extern declaration of %q#D doesn%'t match", x);
+		  warning_at (DECL_SOURCE_LOCATION (oldglobal), 0,
+			      "global declaration %q#D", oldglobal);
+		}
+	    }
+	  /* If we have a local external declaration,
+	     and no file-scope declaration has yet been seen,
+	     then if we later have a file-scope decl it must not be static.  */
+	  if (oldlocal == NULL_TREE
+	      && oldglobal == NULL_TREE
+	      && DECL_EXTERNAL (x)
+	      && TREE_PUBLIC (x))
+	    TREE_PUBLIC (name) = 1;
 
-bool
-template_parm_scope_p (void)
-{
-  return innermost_scope_kind () == sk_template_parms;
-}
+	  /* Don't complain about the parms we push and then pop
+	     while tentatively parsing a function declarator.  */
+	  if (TREE_CODE (x) == PARM_DECL && DECL_CONTEXT (x) == NULL_TREE)
+	    /* Ignore.  */;
 
-/* If KEEP is true, make a BLOCK node for the next binding level,
-   unconditionally.  Otherwise, use the normal logic to decide whether
-   or not to create a BLOCK.  */
+	  /* Warn if shadowing an argument at the top level of the body.  */
+	  else if (oldlocal != NULL_TREE && !DECL_EXTERNAL (x)
+		   /* Inline decls shadow nothing.  */
+		   && !DECL_FROM_INLINE (x)
+		   && (TREE_CODE (oldlocal) == PARM_DECL
+		       || VAR_P (oldlocal)
+                       /* If the old decl is a type decl, only warn if the
+                          old decl is an explicit typedef or if both the old
+                          and new decls are type decls.  */
+                       || (TREE_CODE (oldlocal) == TYPE_DECL
+                           && (!DECL_ARTIFICIAL (oldlocal)
+                               || TREE_CODE (x) == TYPE_DECL)))
+                   /* Don't check for internally generated vars unless
+                      it's an implicit typedef (see create_implicit_typedef
+                      in decl.c) or anonymous union variable.  */
+		   && (!DECL_ARTIFICIAL (x)
+		       || DECL_IMPLICIT_TYPEDEF_P (x)
+		       || (VAR_P (x) && DECL_ANON_UNION_VAR_P (x))))
+	    {
+	      bool nowarn = false;
 
-void
-keep_next_level (bool keep)
-{
-  keep_next_level_flag = keep;
-}
+	      /* Don't complain if it's from an enclosing function.  */
+	      if (DECL_CONTEXT (oldlocal) == current_function_decl
+		  && TREE_CODE (x) != PARM_DECL
+		  && TREE_CODE (oldlocal) == PARM_DECL)
+		{
+		  /* Go to where the parms should be and see if we find
+		     them there.  */
+		  cp_binding_level *b = current_binding_level->level_chain;
 
-/* Return the list of declarations of the current level.
-   Note that this list is in reverse order unless/until
-   you nreverse it; and when you do nreverse it, you must
-   store the result back using `storedecls' or you will lose.  */
+		  if (FUNCTION_NEEDS_BODY_BLOCK (current_function_decl))
+		    /* Skip the ctor/dtor cleanup level.  */
+		    b = b->level_chain;
 
-tree
-getdecls (void)
-{
-  return current_binding_level->names;
-}
+		  /* ARM $8.3 */
+		  if (b->kind == sk_function_parms)
+		    {
+		      error ("declaration of %q#D shadows a parameter", x);
+		      nowarn = true;
+		    }
+		}
 
-/* Return how many function prototypes we are currently nested inside.  */
+	      /* The local structure or class can't use parameters of
+		 the containing function anyway.  */
+	      if (DECL_CONTEXT (oldlocal) != current_function_decl)
+		{
+		  cp_binding_level *scope = current_binding_level;
+		  tree context = DECL_CONTEXT (oldlocal);
+		  for (; scope; scope = scope->level_chain)
+		   {
+		     if (scope->kind == sk_function_parms
+			 && scope->this_entity == context)
+		      break;
+		     if (scope->kind == sk_class
+			 && !LAMBDA_TYPE_P (scope->this_entity))
+		       {
+			 nowarn = true;
+			 break;
+		       }
+		   }
+		}
+	      /* Error if redeclaring a local declared in a
+		 init-statement or in the condition of an if or
+		 switch statement when the new declaration is in the
+		 outermost block of the controlled statement.
+		 Redeclaring a variable from a for or while condition is
+		 detected elsewhere.  */
+	      else if (VAR_P (oldlocal)
+		       && oldscope == current_binding_level->level_chain
+		       && (oldscope->kind == sk_cond
+			   || oldscope->kind == sk_for))
+		{
+		  error ("redeclaration of %q#D", x);
+		  inform (DECL_SOURCE_LOCATION (oldlocal),
+			  "%q#D previously declared here", oldlocal);
+		  nowarn = true;
+		}
+	      /* C++11:
+		 3.3.3/3:  The name declared in an exception-declaration (...)
+		 shall not be redeclared in the outermost block of the handler.
+		 3.3.3/2:  A parameter name shall not be redeclared (...) in
+		 the outermost block of any handler associated with a
+		 function-try-block.
+		 3.4.1/15: The function parameter names shall not be redeclared
+		 in the exception-declaration nor in the outermost block of a
+		 handler for the function-try-block.  */
+	      else if ((VAR_P (oldlocal)
+			&& oldscope == current_binding_level->level_chain
+			&& oldscope->kind == sk_catch)
+		       || (TREE_CODE (oldlocal) == PARM_DECL
+			   && (current_binding_level->kind == sk_catch
+			       || (current_binding_level->level_chain->kind
+				   == sk_catch))
+			   && in_function_try_handler))
+		{
+		  if (permerror (input_location, "redeclaration of %q#D", x))
+		    inform (DECL_SOURCE_LOCATION (oldlocal),
+			    "%q#D previously declared here", oldlocal);
+		  nowarn = true;
+		}
 
-int
-function_parm_depth (void)
-{
-  int level = 0;
-  cp_binding_level *b;
+	      if ((warn_shadow
+		   || warn_shadow_local
+		   || warn_shadow_compatible_local)
+		  && !nowarn)
+		{
+		  bool warned;
+		  enum opt_code warning_code;
+		  /* If '-Wshadow=compatible-local' is specified without other
+		     -Wshadow= flags, we will warn only when the type of the
+		     shadowing variable (i.e. x) can be converted to that of
+		     the shadowed parameter (oldlocal). The reason why we only
+		     check if x's type can be converted to oldlocal's type
+		     (but not the other way around) is because when users
+		     accidentally shadow a parameter, more than often they
+		     would use the variable thinking (mistakenly) it's still
+		     the parameter. It would be rare that users would use the
+		     variable in the place that expects the parameter but
+		     thinking it's a new decl.  */
+		  if (warn_shadow)
+		    warning_code = OPT_Wshadow;
+		  else if (can_convert (TREE_TYPE (oldlocal), TREE_TYPE (x),
+					tf_none))
+		    warning_code = OPT_Wshadow_compatible_local;
+		  else
+		    warning_code = OPT_Wshadow_local;
 
-  for (b = current_binding_level;
-       b->kind == sk_function_parms;
-       b = b->level_chain)
-    ++level;
+		  if (TREE_CODE (oldlocal) == PARM_DECL)
+		    warned = warning_at (input_location, warning_code,
+				"declaration of %q#D shadows a parameter", x);
+		  else if (is_capture_proxy (oldlocal))
+		    warned = warning_at (input_location, warning_code,
+				"declaration of %qD shadows a lambda capture",
+				x);
+		  else
+		    warned = warning_at (input_location, warning_code,
+				"declaration of %qD shadows a previous local",
+				x);
 
-  return level;
-}
+		  if (warned)
+		    inform (DECL_SOURCE_LOCATION (oldlocal),
+			    "shadowed declaration is here");
+		}
+	    }
 
-/* For debugging.  */
-static int no_print_functions = 0;
-static int no_print_builtins = 0;
+	  /* Maybe warn if shadowing something else.  */
+	  else if (warn_shadow && !DECL_EXTERNAL (x)
+                   /* No shadow warnings for internally generated vars unless
+                      it's an implicit typedef (see create_implicit_typedef
+                      in decl.c).  */
+                   && (! DECL_ARTIFICIAL (x) || DECL_IMPLICIT_TYPEDEF_P (x))
+                   /* No shadow warnings for vars made for inlining.  */
+                   && ! DECL_FROM_INLINE (x))
+	    {
+	      tree member;
 
-static void
-print_binding_level (cp_binding_level* lvl)
-{
-  tree t;
-  int i = 0, len;
-  fprintf (stderr, " blocks=%p", (void *) lvl->blocks);
-  if (lvl->more_cleanups_ok)
-    fprintf (stderr, " more-cleanups-ok");
-  if (lvl->have_cleanups)
-    fprintf (stderr, " have-cleanups");
-  fprintf (stderr, "\n");
-  if (lvl->names)
-    {
-      fprintf (stderr, " names:\t");
-      /* We can probably fit 3 names to a line?  */
-      for (t = lvl->names; t; t = TREE_CHAIN (t))
-	{
-	  if (no_print_functions && (TREE_CODE (t) == FUNCTION_DECL))
-	    continue;
-	  if (no_print_builtins
-	      && (TREE_CODE (t) == TYPE_DECL)
-	      && DECL_IS_BUILTIN (t))
-	    continue;
+	      if (nonlambda_method_basetype ())
+		member = lookup_member (current_nonlambda_class_type (),
+					name,
+					/*protect=*/0,
+					/*want_type=*/false,
+					tf_warning_or_error);
+	      else
+		member = NULL_TREE;
 
-	  /* Function decls tend to have longer names.  */
-	  if (TREE_CODE (t) == FUNCTION_DECL)
-	    len = 3;
-	  else
-	    len = 2;
-	  i += len;
-	  if (i > 6)
-	    {
-	      fprintf (stderr, "\n\t");
-	      i = len;
+	      if (member && !TREE_STATIC (member))
+		{
+		  if (BASELINK_P (member))
+		    member = BASELINK_FUNCTIONS (member);
+		  member = OVL_CURRENT (member);
+	
+		  /* Do not warn if a variable shadows a function, unless
+		     the variable is a function or a pointer-to-function.  */
+		  if (TREE_CODE (member) != FUNCTION_DECL
+		      || TREE_CODE (x) == FUNCTION_DECL
+		      || TYPE_PTRFN_P (TREE_TYPE (x))
+		      || TYPE_PTRMEMFUNC_P (TREE_TYPE (x)))
+		    {
+		      if (warning_at (input_location, OPT_Wshadow,
+				      "declaration of %qD shadows a member of %qT",
+				      x, current_nonlambda_class_type ())
+			  && DECL_P (member))
+			inform (DECL_SOURCE_LOCATION (member),
+				"shadowed declaration is here");
+		    }
+		}
+	      else if (oldglobal != NULL_TREE
+		       && (VAR_P (oldglobal)
+                           /* If the old decl is a type decl, only warn if the
+                              old decl is an explicit typedef or if both the
+                              old and new decls are type decls.  */
+                           || (TREE_CODE (oldglobal) == TYPE_DECL
+                               && (!DECL_ARTIFICIAL (oldglobal)
+                                   || TREE_CODE (x) == TYPE_DECL)))
+		       && !instantiating_current_function_p ())
+		/* XXX shadow warnings in outer-more namespaces */
+		{
+		  if (warning_at (input_location, OPT_Wshadow,
+				  "declaration of %qD shadows a "
+				  "global declaration", x))
+		    inform (DECL_SOURCE_LOCATION (oldglobal),
+			    "shadowed declaration is here");
+		}
 	    }
-	  print_node_brief (stderr, "", t, 0);
-	  if (t == error_mark_node)
-	    break;
-	}
-      if (i)
-	fprintf (stderr, "\n");
-    }
-  if (vec_safe_length (lvl->class_shadowed))
-    {
-      size_t i;
-      cp_class_binding *b;
-      fprintf (stderr, " class-shadowed:");
-      FOR_EACH_VEC_ELT (*lvl->class_shadowed, i, b)
-	fprintf (stderr, " %s ", IDENTIFIER_POINTER (b->identifier));
-      fprintf (stderr, "\n");
-    }
-  if (lvl->type_shadowed)
-    {
-      fprintf (stderr, " type-shadowed:");
-      for (t = lvl->type_shadowed; t; t = TREE_CHAIN (t))
-	{
-	  fprintf (stderr, " %s ", IDENTIFIER_POINTER (TREE_PURPOSE (t)));
 	}
-      fprintf (stderr, "\n");
-    }
-}
-
-DEBUG_FUNCTION void
-debug (cp_binding_level &ref)
-{
-  print_binding_level (&ref);
-}
-
-DEBUG_FUNCTION void
-debug (cp_binding_level *ptr)
-{
-  if (ptr)
-    debug (*ptr);
-  else
-    fprintf (stderr, "<nil>\n");
-}
 
-
-void
-print_other_binding_stack (cp_binding_level *stack)
-{
-  cp_binding_level *level;
-  for (level = stack; !global_scope_p (level); level = level->level_chain)
-    {
-      fprintf (stderr, "binding level %p\n", (void *) level);
-      print_binding_level (level);
+      if (VAR_P (x))
+	maybe_register_incomplete_var (x);
     }
-}
 
-void
-print_binding_stack (void)
-{
-  cp_binding_level *b;
-  fprintf (stderr, "current_binding_level=%p\n"
-	   "class_binding_level=%p\n"
-	   "NAMESPACE_LEVEL (global_namespace)=%p\n",
-	   (void *) current_binding_level, (void *) class_binding_level,
-	   (void *) NAMESPACE_LEVEL (global_namespace));
-  if (class_binding_level)
-    {
-      for (b = class_binding_level; b; b = b->level_chain)
-	if (b == current_binding_level)
-	  break;
-      if (b)
-	b = class_binding_level;
-      else
-	b = current_binding_level;
-    }
-  else
-    b = current_binding_level;
-  print_other_binding_stack (b);
-  fprintf (stderr, "global:\n");
-  print_binding_level (NAMESPACE_LEVEL (global_namespace));
-}
-
-/* Return the type associated with ID.  */
+  if (need_new_binding)
+    add_decl_to_level (x,
+		       DECL_NAMESPACE_SCOPE_P (x)
+		       ? NAMESPACE_LEVEL (CP_DECL_CONTEXT (x))
+		       : current_binding_level);
 
-static tree
-identifier_type_value_1 (tree id)
-{
-  /* There is no type with that name, anywhere.  */
-  if (REAL_IDENTIFIER_TYPE_VALUE (id) == NULL_TREE)
-    return NULL_TREE;
-  /* This is not the type marker, but the real thing.  */
-  if (REAL_IDENTIFIER_TYPE_VALUE (id) != global_type_node)
-    return REAL_IDENTIFIER_TYPE_VALUE (id);
-  /* Have to search for it. It must be on the global level, now.
-     Ask lookup_name not to return non-types.  */
-  id = lookup_name_real (id, 2, 1, /*block_p=*/true, 0, 0);
-  if (id)
-    return TREE_TYPE (id);
-  return NULL_TREE;
+  return x;
 }
 
-/* Wrapper for identifier_type_value_1.  */
+/* Wrapper for pushdecl_maybe_friend_1.  */
 
 tree
-identifier_type_value (tree id)
+pushdecl_maybe_friend (tree x, bool is_friend)
 {
   tree ret;
-  timevar_start (TV_NAME_LOOKUP);
-  ret = identifier_type_value_1 (id);
-  timevar_stop (TV_NAME_LOOKUP);
+  bool subtime = timevar_cond_start (TV_NAME_LOOKUP);
+  ret = pushdecl_maybe_friend_1 (x, is_friend);
+  timevar_cond_stop (TV_NAME_LOOKUP, subtime);
   return ret;
 }
 
-
-/* Return the IDENTIFIER_GLOBAL_VALUE of T, for use in common code, since
-   the definition of IDENTIFIER_GLOBAL_VALUE is different for C and C++.  */
+/* Record a decl-node X as belonging to the current lexical scope.  */
 
 tree
-identifier_global_value	(tree t)
+pushdecl (tree x)
 {
-  return IDENTIFIER_GLOBAL_VALUE (t);
+  return pushdecl_maybe_friend (x, false);
 }
 
-/* Push a definition of struct, union or enum tag named ID.  into
-   binding_level B.  DECL is a TYPE_DECL for the type.  We assume that
-   the tag ID is not already defined.  */
+/* Enter DECL into the symbol table, if that's appropriate.  Returns
+   DECL, or a modified version thereof.  */
 
-static void
-set_identifier_type_value_with_scope (tree id, tree decl, cp_binding_level *b)
+tree
+maybe_push_decl (tree decl)
 {
-  tree type;
+  tree type = TREE_TYPE (decl);
 
-  if (b->kind != sk_namespace)
-    {
-      /* Shadow the marker, not the real thing, so that the marker
-	 gets restored later.  */
-      tree old_type_value = REAL_IDENTIFIER_TYPE_VALUE (id);
-      b->type_shadowed
-	= tree_cons (id, old_type_value, b->type_shadowed);
-      type = decl ? TREE_TYPE (decl) : NULL_TREE;
-      TREE_TYPE (b->type_shadowed) = type;
-    }
+  /* Add this decl to the current binding level, but not if it comes
+     from another scope, e.g. a static member variable.  TEM may equal
+     DECL or it may be a previous decl of the same name.  */
+  if (decl == error_mark_node
+      || (TREE_CODE (decl) != PARM_DECL
+	  && DECL_CONTEXT (decl) != NULL_TREE
+	  /* Definitions of namespace members outside their namespace are
+	     possible.  */
+	  && !DECL_NAMESPACE_SCOPE_P (decl))
+      || (TREE_CODE (decl) == TEMPLATE_DECL && !namespace_bindings_p ())
+      || type == unknown_type_node
+      /* The declaration of a template specialization does not affect
+	 the functions available for overload resolution, so we do not
+	 call pushdecl.  */
+      || (TREE_CODE (decl) == FUNCTION_DECL
+	  && DECL_TEMPLATE_SPECIALIZATION (decl)))
+    return decl;
   else
-    {
-      cxx_binding *binding =
-	binding_for_name (NAMESPACE_LEVEL (current_namespace), id);
-      gcc_assert (decl);
-      if (binding->value)
-	supplement_binding (binding, decl);
-      else
-	binding->value = decl;
-
-      /* Store marker instead of real type.  */
-      type = global_type_node;
-    }
-  SET_IDENTIFIER_TYPE_VALUE (id, type);
+    return pushdecl (decl);
 }
 
-/* As set_identifier_type_value_with_scope, but using
-   current_binding_level.  */
+/* Bind DECL to ID in the current_binding_level, assumed to be a local
+   binding level.  If PUSH_USING is set in FLAGS, we know that DECL
+   doesn't really belong to this binding level, that it got here
+   through a using-declaration.  */
 
 void
-set_identifier_type_value (tree id, tree decl)
+push_local_binding (tree id, tree decl, int flags)
 {
-  set_identifier_type_value_with_scope (id, decl, current_binding_level);
-}
+  cp_binding_level *b;
 
-/* Return the name for the constructor (or destructor) for the
-   specified class TYPE.  When given a template, this routine doesn't
-   lose the specialization.  */
+  /* Skip over any local classes.  This makes sense if we call
+     push_local_binding with a friend decl of a local class.  */
+  b = innermost_nonclass_level ();
 
-static inline tree
-constructor_name_full (tree type)
-{
-  return TYPE_IDENTIFIER (TYPE_MAIN_VARIANT (type));
-}
+  if (lookup_name_innermost_nonclass_level (id))
+    {
+      /* Supplement the existing binding.  */
+      if (!supplement_binding (IDENTIFIER_BINDING (id), decl))
+	/* It didn't work.  Something else must be bound at this
+	   level.  Do not add DECL to the list of things to pop
+	   later.  */
+	return;
+    }
+  else
+    /* Create a new binding.  */
+    push_binding (id, decl, b);
 
-/* Return the name for the constructor (or destructor) for the
-   specified class.  When given a template, return the plain
-   unspecialized name.  */
+  if (TREE_CODE (decl) == OVERLOAD || (flags & PUSH_USING))
+    /* We must put the OVERLOAD into a TREE_LIST since the
+       TREE_CHAIN of an OVERLOAD is already used.  Similarly for
+       decls that got here through a using-declaration.  */
+    decl = build_tree_list (NULL_TREE, decl);
 
-tree
-constructor_name (tree type)
-{
-  tree name;
-  name = constructor_name_full (type);
-  if (IDENTIFIER_TEMPLATE (name))
-    name = IDENTIFIER_TEMPLATE (name);
-  return name;
+  /* And put DECL on the list of things declared by the current
+     binding level.  */
+  add_decl_to_level (decl, b);
 }
 
-/* Returns TRUE if NAME is the name for the constructor for TYPE,
-   which must be a class type.  */
+/* Check to see whether or not DECL is a variable that would have been
+   in scope under the ARM, but is not in scope under the ANSI/ISO
+   standard.  If so, issue an error message.  If name lookup would
+   work in both cases, but return a different result, this function
+   returns the result of ANSI/ISO lookup.  Otherwise, it returns
+   DECL.  */
 
-bool
-constructor_name_p (tree name, tree type)
+tree
+check_for_out_of_scope_variable (tree decl)
 {
-  tree ctor_name;
-
-  gcc_assert (MAYBE_CLASS_TYPE_P (type));
-
-  if (!name)
-    return false;
-
-  if (!identifier_p (name))
-    return false;
+  tree shadowed;
 
-  /* These don't have names.  */
-  if (TREE_CODE (type) == DECLTYPE_TYPE
-      || TREE_CODE (type) == TYPEOF_TYPE)
-    return false;
+  /* We only care about out of scope variables.  */
+  if (!(VAR_P (decl) && DECL_DEAD_FOR_LOCAL (decl)))
+    return decl;
 
-  ctor_name = constructor_name_full (type);
-  if (name == ctor_name)
-    return true;
-  if (IDENTIFIER_TEMPLATE (ctor_name)
-      && name == IDENTIFIER_TEMPLATE (ctor_name))
-    return true;
-  return false;
-}
+  shadowed = DECL_HAS_SHADOWED_FOR_VAR_P (decl)
+    ? DECL_SHADOWED_FOR_VAR (decl) : NULL_TREE ;
+  while (shadowed != NULL_TREE && VAR_P (shadowed)
+	 && DECL_DEAD_FOR_LOCAL (shadowed))
+    shadowed = DECL_HAS_SHADOWED_FOR_VAR_P (shadowed)
+      ? DECL_SHADOWED_FOR_VAR (shadowed) : NULL_TREE;
+  if (!shadowed)
+    shadowed = IDENTIFIER_NAMESPACE_VALUE (DECL_NAME (decl));
+  if (shadowed)
+    {
+      if (!DECL_ERROR_REPORTED (decl))
+	{
+	  warning (0, "name lookup of %qD changed", DECL_NAME (decl));
+	  warning_at (DECL_SOURCE_LOCATION (shadowed), 0,
+		      "  matches this %qD under ISO standard rules",
+		      shadowed);
+	  warning_at (DECL_SOURCE_LOCATION (decl), 0,
+		      "  matches this %qD under old rules", decl);
+	  DECL_ERROR_REPORTED (decl) = 1;
+	}
+      return shadowed;
+    }
 
-/* Counter used to create anonymous type names.  */
+  /* If we have already complained about this declaration, there's no
+     need to do it again.  */
+  if (DECL_ERROR_REPORTED (decl))
+    return decl;
 
-static GTY(()) int anon_cnt;
+  DECL_ERROR_REPORTED (decl) = 1;
 
-/* Return an IDENTIFIER which can be used as a name for
-   unnamed structs and unions.  */
+  if (TREE_TYPE (decl) == error_mark_node)
+    return decl;
 
-tree
-make_anon_name (void)
-{
-  char buf[32];
+  if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (TREE_TYPE (decl)))
+    {
+      error ("name lookup of %qD changed for ISO %<for%> scoping",
+	     DECL_NAME (decl));
+      error ("  cannot use obsolete binding at %q+D because "
+	     "it has a destructor", decl);
+      return error_mark_node;
+    }
+  else
+    {
+      permerror (input_location, "name lookup of %qD changed for ISO %<for%> scoping",
+	         DECL_NAME (decl));
+      if (flag_permissive)
+        permerror (DECL_SOURCE_LOCATION (decl),
+		   "  using obsolete binding at %qD", decl);
+      else
+	{
+	  static bool hint;
+	  if (!hint)
+	    {
+	      inform (input_location, "(if you use %<-fpermissive%> G++ will accept your code)");
+	      hint = true;
+	    }
+	}
+    }
 
-  sprintf (buf, anon_aggrname_format (), anon_cnt++);
-  return get_identifier (buf);
+  return decl;
 }
+
+/* true means unconditionally make a BLOCK for the next level pushed.  */
 
-/* This code is practically identical to that for creating
-   anonymous names, but is just used for lambdas instead.  This isn't really
-   necessary, but it's convenient to avoid treating lambdas like other
-   unnamed types.  */
+static bool keep_next_level_flag;
 
-static GTY(()) int lambda_cnt = 0;
+static int binding_depth = 0;
 
-tree
-make_lambda_name (void)
+static void
+indent (int depth)
 {
-  char buf[32];
+  int i;
 
-  sprintf (buf, LAMBDANAME_FORMAT, lambda_cnt++);
-  return get_identifier (buf);
+  for (i = 0; i < depth * 2; i++)
+    putc (' ', stderr);
 }
 
-/* Return (from the stack of) the BINDING, if any, established at SCOPE.  */
-
-static inline cxx_binding *
-find_binding (cp_binding_level *scope, cxx_binding *binding)
+/* Return a string describing the kind of SCOPE we have.  */
+static const char *
+cp_binding_level_descriptor (cp_binding_level *scope)
 {
-  for (; binding != NULL; binding = binding->previous)
-    if (binding->scope == scope)
-      return binding;
+  /* The order of this table must match the "scope_kind"
+     enumerators.  */
+  static const char* scope_kind_names[] = {
+    "block-scope",
+    "cleanup-scope",
+    "try-scope",
+    "catch-scope",
+    "for-scope",
+    "function-parameter-scope",
+    "class-scope",
+    "namespace-scope",
+    "template-parameter-scope",
+    "template-explicit-spec-scope"
+  };
+  const scope_kind kind = scope->explicit_spec_p
+    ? sk_template_spec : scope->kind;
 
-  return (cxx_binding *)0;
+  return scope_kind_names[kind];
 }
 
-/* Return the binding for NAME in SCOPE, if any.  Otherwise, return NULL.  */
-
-static inline cxx_binding *
-cp_binding_level_find_binding_for_name (cp_binding_level *scope, tree name)
+/* Output a debugging information about SCOPE when performing
+   ACTION at LINE.  */
+static void
+cp_binding_level_debug (cp_binding_level *scope, int line, const char *action)
 {
-  cxx_binding *b = IDENTIFIER_NAMESPACE_BINDINGS (name);
-  if (b)
-    {
-      /* Fold-in case where NAME is used only once.  */
-      if (scope == b->scope && b->previous == NULL)
-	return b;
-      return find_binding (scope, b);
-    }
-  return NULL;
+  const char *desc = cp_binding_level_descriptor (scope);
+  if (scope->this_entity)
+    verbatim ("%s %s(%E) %p %d\n", action, desc,
+	      scope->this_entity, (void *) scope, line);
+  else
+    verbatim ("%s %s %p %d\n", action, desc, (void *) scope, line);
 }
 
-/* Always returns a binding for name in scope.  If no binding is
-   found, make a new one.  */
+/* Return the estimated initial size of the hashtable of a NAMESPACE
+   scope.  */
 
-static cxx_binding *
-binding_for_name (cp_binding_level *scope, tree name)
+static inline size_t
+namespace_scope_ht_size (tree ns)
 {
-  cxx_binding *result;
+  tree name = DECL_NAME (ns);
 
-  result = cp_binding_level_find_binding_for_name (scope, name);
-  if (result)
-    return result;
-  /* Not found, make a new one.  */
-  result = cxx_binding_make (NULL, NULL);
-  result->previous = IDENTIFIER_NAMESPACE_BINDINGS (name);
-  result->scope = scope;
-  result->is_local = false;
-  result->value_is_inherited = false;
-  IDENTIFIER_NAMESPACE_BINDINGS (name) = result;
-  return result;
+  return name == std_identifier
+    ? NAMESPACE_STD_HT_SIZE
+    : (name == global_scope_name
+       ? GLOBAL_SCOPE_HT_SIZE
+       : NAMESPACE_ORDINARY_HT_SIZE);
 }
 
-/* Walk through the bindings associated to the name of FUNCTION,
-   and return the first declaration of a function with a
-   "C" linkage specification, a.k.a 'extern "C"'.
-   This function looks for the binding, regardless of which scope it
-   has been defined in. It basically looks in all the known scopes.
-   Note that this function does not lookup for bindings of builtin functions
-   or for functions declared in system headers.  */
-static tree
-lookup_extern_c_fun_in_all_ns (tree function)
-{
-  tree name;
-  cxx_binding *iter;
+/* A chain of binding_level structures awaiting reuse.  */
 
-  gcc_assert (function && TREE_CODE (function) == FUNCTION_DECL);
+static GTY((deletable)) cp_binding_level *free_binding_level;
 
-  name = DECL_NAME (function);
-  gcc_assert (name && identifier_p (name));
+/* Insert SCOPE as the innermost binding level.  */
 
-  for (iter = IDENTIFIER_NAMESPACE_BINDINGS (name);
-       iter;
-       iter = iter->previous)
+void
+push_binding_level (cp_binding_level *scope)
+{
+  /* Add it to the front of currently active scopes stack.  */
+  scope->level_chain = current_binding_level;
+  current_binding_level = scope;
+  keep_next_level_flag = false;
+
+  if (ENABLE_SCOPE_CHECKING)
     {
-      tree ovl;
-      for (ovl = iter->value; ovl; ovl = OVL_NEXT (ovl))
-	{
-	  tree decl = OVL_CURRENT (ovl);
-	  if (decl
-	      && TREE_CODE (decl) == FUNCTION_DECL
-	      && DECL_EXTERN_C_P (decl)
-	      && !DECL_ARTIFICIAL (decl))
-	    {
-	      return decl;
-	    }
-	}
+      scope->binding_depth = binding_depth;
+      indent (binding_depth);
+      cp_binding_level_debug (scope, LOCATION_LINE (input_location),
+			      "push");
+      binding_depth++;
     }
-  return NULL;
 }
 
-/* Returns a list of C-linkage decls with the name NAME.  */
+/* Create a new KIND scope and make it the top of the active scopes stack.
+   ENTITY is the scope of the associated C++ entity (namespace, class,
+   function, C++0x enumeration); it is NULL otherwise.  */
 
-tree
-c_linkage_bindings (tree name)
+cp_binding_level *
+begin_scope (scope_kind kind, tree entity)
 {
-  tree decls = NULL_TREE;
-  cxx_binding *iter;
+  cp_binding_level *scope;
 
-  for (iter = IDENTIFIER_NAMESPACE_BINDINGS (name);
-       iter;
-       iter = iter->previous)
+  /* Reuse or create a struct for this binding level.  */
+  if (!ENABLE_SCOPE_CHECKING && free_binding_level)
     {
-      tree ovl;
-      for (ovl = iter->value; ovl; ovl = OVL_NEXT (ovl))
-	{
-	  tree decl = OVL_CURRENT (ovl);
-	  if (decl
-	      && DECL_EXTERN_C_P (decl)
-	      && !DECL_ARTIFICIAL (decl))
-	    {
-	      if (decls == NULL_TREE)
-		decls = decl;
-	      else
-		decls = tree_cons (NULL_TREE, decl, decls);
-	    }
-	}
+      scope = free_binding_level;
+      free_binding_level = scope->level_chain;
+      memset (scope, 0, sizeof (cp_binding_level));
     }
-  return decls;
-}
+  else
+    scope = ggc_cleared_alloc<cp_binding_level> ();
 
-/* Insert another USING_DECL into the current binding level, returning
-   this declaration. If this is a redeclaration, do nothing, and
-   return NULL_TREE if this not in namespace scope (in namespace
-   scope, a using decl might extend any previous bindings).  */
+  scope->this_entity = entity;
+  scope->more_cleanups_ok = true;
+  switch (kind)
+    {
+    case sk_cleanup:
+      scope->keep = true;
+      break;
 
-static tree
-push_using_decl_1 (tree scope, tree name)
-{
-  tree decl;
+    case sk_template_spec:
+      scope->explicit_spec_p = true;
+      kind = sk_template_parms;
+      /* Fall through.  */
+    case sk_template_parms:
+    case sk_block:
+    case sk_try:
+    case sk_catch:
+    case sk_for:
+    case sk_cond:
+    case sk_class:
+    case sk_scoped_enum:
+    case sk_function_parms:
+    case sk_transaction:
+    case sk_omp:
+      scope->keep = keep_next_level_flag;
+      break;
 
-  gcc_assert (TREE_CODE (scope) == NAMESPACE_DECL);
-  gcc_assert (identifier_p (name));
-  for (decl = current_binding_level->usings; decl; decl = DECL_CHAIN (decl))
-    if (USING_DECL_SCOPE (decl) == scope && DECL_NAME (decl) == name)
+    case sk_namespace:
+      NAMESPACE_LEVEL (entity) = scope;
+      vec_alloc (scope->static_decls,
+		 (DECL_NAME (entity) == std_identifier
+		  || DECL_NAME (entity) == global_scope_name) ? 200 : 10);
       break;
-  if (decl)
-    return namespace_bindings_p () ? decl : NULL_TREE;
-  decl = build_lang_decl (USING_DECL, name, NULL_TREE);
-  USING_DECL_SCOPE (decl) = scope;
-  DECL_CHAIN (decl) = current_binding_level->usings;
-  current_binding_level->usings = decl;
-  return decl;
+
+    default:
+      /* Should not happen.  */
+      gcc_unreachable ();
+      break;
+    }
+  scope->kind = kind;
+
+  push_binding_level (scope);
+
+  return scope;
 }
 
-/* Wrapper for push_using_decl_1.  */
+/* We're about to leave current scope.  Pop the top of the stack of
+   currently active scopes.  Return the enclosing scope, now active.  */
 
-static tree
-push_using_decl (tree scope, tree name)
+cp_binding_level *
+leave_scope (void)
 {
-  tree ret;
-  timevar_start (TV_NAME_LOOKUP);
-  ret = push_using_decl_1 (scope, name);
-  timevar_stop (TV_NAME_LOOKUP);
-  return ret;
-}
+  cp_binding_level *scope = current_binding_level;
 
-/* Same as pushdecl, but define X in binding-level LEVEL.  We rely on the
-   caller to set DECL_CONTEXT properly.
+  if (scope->kind == sk_namespace && class_binding_level)
+    current_binding_level = class_binding_level;
 
-   Note that this must only be used when X will be the new innermost
-   binding for its name, as we tack it onto the front of IDENTIFIER_BINDING
-   without checking to see if the current IDENTIFIER_BINDING comes from a
-   closer binding level than LEVEL.  */
+  /* We cannot leave a scope, if there are none left.  */
+  if (NAMESPACE_LEVEL (global_namespace))
+    gcc_assert (!global_scope_p (scope));
 
-static tree
-pushdecl_with_scope_1 (tree x, cp_binding_level *level, bool is_friend)
-{
-  cp_binding_level *b;
-  tree function_decl = current_function_decl;
+  if (ENABLE_SCOPE_CHECKING)
+    {
+      indent (--binding_depth);
+      cp_binding_level_debug (scope, LOCATION_LINE (input_location),
+			      "leave");
+    }
 
-  current_function_decl = NULL_TREE;
-  if (level->kind == sk_class)
+  /* Move one nesting level up.  */
+  current_binding_level = scope->level_chain;
+
+  /* Namespace-scopes are left most probably temporarily, not
+     completely; they can be reopened later, e.g. in namespace-extension
+     or any name binding activity that requires us to resume a
+     namespace.  For classes, we cache some binding levels.  For other
+     scopes, we just make the structure available for reuse.  */
+  if (scope->kind != sk_namespace
+      && scope->kind != sk_class)
     {
-      b = class_binding_level;
-      class_binding_level = level;
-      pushdecl_class_level (x);
-      class_binding_level = b;
+      scope->level_chain = free_binding_level;
+      gcc_assert (!ENABLE_SCOPE_CHECKING
+		  || scope->binding_depth == binding_depth);
+      free_binding_level = scope;
     }
-  else
+
+  if (scope->kind == sk_class)
     {
-      b = current_binding_level;
-      current_binding_level = level;
-      x = pushdecl_maybe_friend (x, is_friend);
-      current_binding_level = b;
+      /* Reset DEFINING_CLASS_P to allow for reuse of a
+	 class-defining scope in a non-defining context.  */
+      scope->defining_class_p = 0;
+
+      /* Find the innermost enclosing class scope, and reset
+	 CLASS_BINDING_LEVEL appropriately.  */
+      class_binding_level = NULL;
+      for (scope = current_binding_level; scope; scope = scope->level_chain)
+	if (scope->kind == sk_class)
+	  {
+	    class_binding_level = scope;
+	    break;
+	  }
     }
-  current_function_decl = function_decl;
-  return x;
+
+  return current_binding_level;
 }
- 
-/* Wrapper for pushdecl_with_scope_1.  */
 
-tree
-pushdecl_with_scope (tree x, cp_binding_level *level, bool is_friend)
+static void
+resume_scope (cp_binding_level* b)
 {
-  tree ret;
-  bool subtime = timevar_cond_start (TV_NAME_LOOKUP);
-  ret = pushdecl_with_scope_1 (x, level, is_friend);
-  timevar_cond_stop (TV_NAME_LOOKUP, subtime);
-  return ret;
+  /* Resuming binding levels is meant only for namespaces,
+     and those cannot nest into classes.  */
+  gcc_assert (!class_binding_level);
+  /* Also, resuming a non-directly nested namespace is a no-no.  */
+  gcc_assert (b->level_chain == current_binding_level);
+  current_binding_level = b;
+  if (ENABLE_SCOPE_CHECKING)
+    {
+      b->binding_depth = binding_depth;
+      indent (binding_depth);
+      cp_binding_level_debug (b, LOCATION_LINE (input_location), "resume");
+      binding_depth++;
+    }
 }
 
-/* Helper function for push_overloaded_decl_1 and do_nonmember_using_decl.
-   Compares the parameter-type-lists of DECL1 and DECL2 and returns false
-   if they are different.  If the DECLs are template functions, the return
-   types and the template parameter lists are compared too (DR 565).  */
+/* Return the innermost binding level that is not for a class scope.  */
 
-static bool
-compparms_for_decl_and_using_decl (tree decl1, tree decl2)
+static cp_binding_level *
+innermost_nonclass_level (void)
 {
-  if (!compparms (TYPE_ARG_TYPES (TREE_TYPE (decl1)),
-		  TYPE_ARG_TYPES (TREE_TYPE (decl2))))
-    return false;
+  cp_binding_level *b;
 
-  if (! DECL_FUNCTION_TEMPLATE_P (decl1)
-      || ! DECL_FUNCTION_TEMPLATE_P (decl2))
-    return true;
+  b = current_binding_level;
+  while (b->kind == sk_class)
+    b = b->level_chain;
 
-  return (comp_template_parms (DECL_TEMPLATE_PARMS (decl1),
-			       DECL_TEMPLATE_PARMS (decl2))
-	  && same_type_p (TREE_TYPE (TREE_TYPE (decl1)),
-			  TREE_TYPE (TREE_TYPE (decl2))));
+  return b;
 }
 
-/* DECL is a FUNCTION_DECL for a non-member function, which may have
-   other definitions already in place.  We get around this by making
-   the value of the identifier point to a list of all the things that
-   want to be referenced by that name.  It is then up to the users of
-   that name to decide what to do with that list.
-
-   DECL may also be a TEMPLATE_DECL, with a FUNCTION_DECL in its
-   DECL_TEMPLATE_RESULT.  It is dealt with the same way.
-
-   FLAGS is a bitwise-or of the following values:
-     PUSH_LOCAL: Bind DECL in the current scope, rather than at
-		 namespace scope.
-     PUSH_USING: DECL is being pushed as the result of a using
-		 declaration.
-
-   IS_FRIEND is true if this is a friend declaration.
-
-   The value returned may be a previous declaration if we guessed wrong
-   about what language DECL should belong to (C or C++).  Otherwise,
-   it's always DECL (and never something that's not a _DECL).  */
+/* We're defining an object of type TYPE.  If it needs a cleanup, but
+   we're not allowed to add any more objects with cleanups to the current
+   scope, create a new binding level.  */
 
-static tree
-push_overloaded_decl_1 (tree decl, int flags, bool is_friend)
+void
+maybe_push_cleanup_level (tree type)
 {
-  tree name = DECL_NAME (decl);
-  tree old;
-  tree new_binding;
-  int doing_global = (namespace_bindings_p () || !(flags & PUSH_LOCAL));
-
-  if (doing_global)
-    old = namespace_binding (name, DECL_CONTEXT (decl));
-  else
-    old = lookup_name_innermost_nonclass_level (name);
-
-  if (old)
+  if (type != error_mark_node
+      && TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type)
+      && current_binding_level->more_cleanups_ok == 0)
     {
-      if (TREE_CODE (old) == TYPE_DECL && DECL_ARTIFICIAL (old))
-	{
-	  tree t = TREE_TYPE (old);
-	  if (MAYBE_CLASS_TYPE_P (t) && warn_shadow
-	      && (! DECL_IN_SYSTEM_HEADER (decl)
-		  || ! DECL_IN_SYSTEM_HEADER (old)))
-	    warning (OPT_Wshadow, "%q#D hides constructor for %q#T", decl, t);
-	  old = NULL_TREE;
-	}
-      else if (is_overloaded_fn (old))
-	{
-	  tree tmp;
+      begin_scope (sk_cleanup, NULL);
+      current_binding_level->statement_list = push_stmt_list ();
+    }
+}
 
-	  for (tmp = old; tmp; tmp = OVL_NEXT (tmp))
-	    {
-	      tree fn = OVL_CURRENT (tmp);
-	      tree dup;
+/* Return true if we are in the global binding level.  */
 
-	      if (TREE_CODE (tmp) == OVERLOAD && OVL_USED (tmp)
-		  && !(flags & PUSH_USING)
-		  && compparms_for_decl_and_using_decl (fn, decl)
-		  && ! decls_match (fn, decl))
-		diagnose_name_conflict (decl, fn);
+bool
+global_bindings_p (void)
+{
+  return global_scope_p (current_binding_level);
+}
 
-	      dup = duplicate_decls (decl, fn, is_friend);
-	      /* If DECL was a redeclaration of FN -- even an invalid
-		 one -- pass that information along to our caller.  */
-	      if (dup == fn || dup == error_mark_node)
-		return dup;
-	    }
+/* True if we are currently in a toplevel binding level.  This
+   means either the global binding level or a namespace in a toplevel
+   binding level.  Since there are no non-toplevel namespace levels,
+   this really means any namespace or template parameter level.  We
+   also include a class whose context is toplevel.  */
 
-	  /* We don't overload implicit built-ins.  duplicate_decls()
-	     may fail to merge the decls if the new decl is e.g. a
-	     template function.  */
-	  if (TREE_CODE (old) == FUNCTION_DECL
-	      && DECL_ANTICIPATED (old)
-	      && !DECL_HIDDEN_FRIEND_P (old))
-	    old = NULL;
-	}
-      else if (old == error_mark_node)
-	/* Ignore the undefined symbol marker.  */
-	old = NULL_TREE;
-      else
-	{
-	  error ("previous non-function declaration %q+#D", old);
-	  error ("conflicts with function declaration %q#D", decl);
-	  return decl;
-	}
-    }
+bool
+toplevel_bindings_p (void)
+{
+  cp_binding_level *b = innermost_nonclass_level ();
 
-  if (old || TREE_CODE (decl) == TEMPLATE_DECL
-      /* If it's a using declaration, we always need to build an OVERLOAD,
-	 because it's the only way to remember that the declaration comes
-	 from 'using', and have the lookup behave correctly.  */
-      || (flags & PUSH_USING))
-    {
-      if (old && TREE_CODE (old) != OVERLOAD)
-	/* Wrap the existing single decl in an overload.  */
-	new_binding = ovl_cons (old, NULL_TREE);
-      else
-	new_binding = old;
-      new_binding = ovl_cons (decl, new_binding);
-      if (flags & PUSH_USING)
-	OVL_USED (new_binding) = 1;
-    }
-  else
-    /* NAME is not ambiguous.  */
-    new_binding = decl;
+  return b->kind == sk_namespace || b->kind == sk_template_parms;
+}
 
-  if (doing_global)
-    set_namespace_binding (name, current_namespace, new_binding);
-  else
-    {
-      /* We only create an OVERLOAD if there was a previous binding at
-	 this level, or if decl is a template. In the former case, we
-	 need to remove the old binding and replace it with the new
-	 binding.  We must also run through the NAMES on the binding
-	 level where the name was bound to update the chain.  */
+/* True if this is a namespace scope, or if we are defining a class
+   which is itself at namespace scope, or whose enclosing class is
+   such a class, etc.  */
 
-      if (TREE_CODE (new_binding) == OVERLOAD && old)
-	{
-	  tree *d;
+bool
+namespace_bindings_p (void)
+{
+  cp_binding_level *b = innermost_nonclass_level ();
 
-	  for (d = &IDENTIFIER_BINDING (name)->scope->names;
-	       *d;
-	       d = &TREE_CHAIN (*d))
-	    if (*d == old
-		|| (TREE_CODE (*d) == TREE_LIST
-		    && TREE_VALUE (*d) == old))
-	      {
-		if (TREE_CODE (*d) == TREE_LIST)
-		  /* Just replace the old binding with the new.  */
-		  TREE_VALUE (*d) = new_binding;
-		else
-		  /* Build a TREE_LIST to wrap the OVERLOAD.  */
-		  *d = tree_cons (NULL_TREE, new_binding,
-				  TREE_CHAIN (*d));
+  return b->kind == sk_namespace;
+}
 
-		/* And update the cxx_binding node.  */
-		IDENTIFIER_BINDING (name)->value = new_binding;
-		return decl;
-	      }
+/* True if the innermost non-class scope is a block scope.  */
 
-	  /* We should always find a previous binding in this case.  */
-	  gcc_unreachable ();
-	}
+bool
+local_bindings_p (void)
+{
+  cp_binding_level *b = innermost_nonclass_level ();
+  return b->kind < sk_function_parms || b->kind == sk_omp;
+}
 
-      /* Install the new binding.  */
-      push_local_binding (name, new_binding, flags);
-    }
+/* True if the current level needs to have a BLOCK made.  */
 
-  return decl;
+bool
+kept_level_p (void)
+{
+  return (current_binding_level->blocks != NULL_TREE
+	  || current_binding_level->keep
+	  || current_binding_level->kind == sk_cleanup
+	  || current_binding_level->names != NULL_TREE
+	  || current_binding_level->using_directives);
 }
 
-/* Wrapper for push_overloaded_decl_1.  */
+/* Returns the kind of the innermost scope.  */
 
-static tree
-push_overloaded_decl (tree decl, int flags, bool is_friend)
+scope_kind
+innermost_scope_kind (void)
 {
-  tree ret;
-  bool subtime = timevar_cond_start (TV_NAME_LOOKUP);
-  ret = push_overloaded_decl_1 (decl, flags, is_friend);
-  timevar_cond_stop (TV_NAME_LOOKUP, subtime);
-  return ret;
+  return current_binding_level->kind;
 }
 
-/* Check a non-member using-declaration. Return the name and scope
-   being used, and the USING_DECL, or NULL_TREE on failure.  */
+/* Returns true if this scope was created to store template parameters.  */
 
-static tree
-validate_nonmember_using_decl (tree decl, tree scope, tree name)
+bool
+template_parm_scope_p (void)
 {
-  /* [namespace.udecl]
-       A using-declaration for a class member shall be a
-       member-declaration.  */
-  if (TYPE_P (scope))
-    {
-      error ("%qT is not a namespace or unscoped enum", scope);
-      return NULL_TREE;
-    }
-  else if (scope == error_mark_node)
-    return NULL_TREE;
+  return innermost_scope_kind () == sk_template_parms;
+}
 
-  if (TREE_CODE (decl) == TEMPLATE_ID_EXPR)
-    {
-      /* 7.3.3/5
-	   A using-declaration shall not name a template-id.  */
-      error ("a using-declaration cannot specify a template-id.  "
-	     "Try %<using %D%>", name);
-      return NULL_TREE;
-    }
+/* If KEEP is true, make a BLOCK node for the next binding level,
+   unconditionally.  Otherwise, use the normal logic to decide whether
+   or not to create a BLOCK.  */
 
-  if (TREE_CODE (decl) == NAMESPACE_DECL)
-    {
-      error ("namespace %qD not allowed in using-declaration", decl);
-      return NULL_TREE;
-    }
+void
+keep_next_level (bool keep)
+{
+  keep_next_level_flag = keep;
+}
 
-  if (TREE_CODE (decl) == SCOPE_REF)
-    {
-      /* It's a nested name with template parameter dependent scope.
-	 This can only be using-declaration for class member.  */
-      error ("%qT is not a namespace", TREE_OPERAND (decl, 0));
-      return NULL_TREE;
-    }
+/* Return the list of declarations of the current level.
+   Note that this list is in reverse order unless/until
+   you nreverse it; and when you do nreverse it, you must
+   store the result back using `storedecls' or you will lose.  */
 
-  if (is_overloaded_fn (decl))
-    decl = get_first_fn (decl);
+tree
+getdecls (void)
+{
+  return current_binding_level->names;
+}
 
-  gcc_assert (DECL_P (decl));
+/* Return how many function prototypes we are currently nested inside.  */
 
-  /* Make a USING_DECL.  */
-  tree using_decl = push_using_decl (scope, name);
+int
+function_parm_depth (void)
+{
+  int level = 0;
+  cp_binding_level *b;
 
-  if (using_decl == NULL_TREE
-      && at_function_scope_p ()
-      && VAR_P (decl))
-    /* C++11 7.3.3/10.  */
-    error ("%qD is already declared in this scope", name);
-  
-  return using_decl;
+  for (b = current_binding_level;
+       b->kind == sk_function_parms;
+       b = b->level_chain)
+    ++level;
+
+  return level;
 }
 
-/* Process local and global using-declarations.  */
+/* For debugging.  */
+static int no_print_functions = 0;
+static int no_print_builtins = 0;
 
 static void
-do_nonmember_using_decl (tree scope, tree name, tree oldval, tree oldtype,
-			 tree *newval, tree *newtype)
+print_binding_level (cp_binding_level* lvl)
 {
-  struct scope_binding decls = EMPTY_SCOPE_BINDING;
-
-  *newval = *newtype = NULL_TREE;
-  if (!qualified_lookup_using_namespace (name, scope, &decls, 0))
-    /* Lookup error */
-    return;
+  tree t;
+  int i = 0, len;
+  fprintf (stderr, " blocks=%p", (void *) lvl->blocks);
+  if (lvl->more_cleanups_ok)
+    fprintf (stderr, " more-cleanups-ok");
+  if (lvl->have_cleanups)
+    fprintf (stderr, " have-cleanups");
+  fprintf (stderr, "\n");
+  if (lvl->names)
+    {
+      fprintf (stderr, " names:\t");
+      /* We can probably fit 3 names to a line?  */
+      for (t = lvl->names; t; t = TREE_CHAIN (t))
+	{
+	  if (no_print_functions && (TREE_CODE (t) == FUNCTION_DECL))
+	    continue;
+	  if (no_print_builtins
+	      && (TREE_CODE (t) == TYPE_DECL)
+	      && DECL_IS_BUILTIN (t))
+	    continue;
 
-  if (!decls.value && !decls.type)
+	  /* Function decls tend to have longer names.  */
+	  if (TREE_CODE (t) == FUNCTION_DECL)
+	    len = 3;
+	  else
+	    len = 2;
+	  i += len;
+	  if (i > 6)
+	    {
+	      fprintf (stderr, "\n\t");
+	      i = len;
+	    }
+	  print_node_brief (stderr, "", t, 0);
+	  if (t == error_mark_node)
+	    break;
+	}
+      if (i)
+	fprintf (stderr, "\n");
+    }
+  if (vec_safe_length (lvl->class_shadowed))
     {
-      error ("%qD not declared", name);
-      return;
+      size_t i;
+      cp_class_binding *b;
+      fprintf (stderr, " class-shadowed:");
+      FOR_EACH_VEC_ELT (*lvl->class_shadowed, i, b)
+	fprintf (stderr, " %s ", IDENTIFIER_POINTER (b->identifier));
+      fprintf (stderr, "\n");
     }
-
-  /* Shift the old and new bindings around so we're comparing class and
-     enumeration names to each other.  */
-  if (oldval && DECL_IMPLICIT_TYPEDEF_P (oldval))
+  if (lvl->type_shadowed)
     {
-      oldtype = oldval;
-      oldval = NULL_TREE;
+      fprintf (stderr, " type-shadowed:");
+      for (t = lvl->type_shadowed; t; t = TREE_CHAIN (t))
+	{
+	  fprintf (stderr, " %s ", IDENTIFIER_POINTER (TREE_PURPOSE (t)));
+	}
+      fprintf (stderr, "\n");
     }
+}
 
-  if (decls.value && DECL_IMPLICIT_TYPEDEF_P (decls.value))
+DEBUG_FUNCTION void
+debug (cp_binding_level &ref)
+{
+  print_binding_level (&ref);
+}
+
+DEBUG_FUNCTION void
+debug (cp_binding_level *ptr)
+{
+  if (ptr)
+    debug (*ptr);
+  else
+    fprintf (stderr, "<nil>\n");
+}
+
+
+void
+print_other_binding_stack (cp_binding_level *stack)
+{
+  cp_binding_level *level;
+  for (level = stack; !global_scope_p (level); level = level->level_chain)
     {
-      decls.type = decls.value;
-      decls.value = NULL_TREE;
+      fprintf (stderr, "binding level %p\n", (void *) level);
+      print_binding_level (level);
     }
+}
 
-  if (decls.value)
+void
+print_binding_stack (void)
+{
+  cp_binding_level *b;
+  fprintf (stderr, "current_binding_level=%p\n"
+	   "class_binding_level=%p\n"
+	   "NAMESPACE_LEVEL (global_namespace)=%p\n",
+	   (void *) current_binding_level, (void *) class_binding_level,
+	   (void *) NAMESPACE_LEVEL (global_namespace));
+  if (class_binding_level)
     {
-      /* Check for using functions.  */
-      if (is_overloaded_fn (decls.value))
-	{
-	  tree tmp, tmp1;
-
-	  if (oldval && !is_overloaded_fn (oldval))
-	    {
-	      error ("%qD is already declared in this scope", name);
-	      oldval = NULL_TREE;
-	    }
+      for (b = class_binding_level; b; b = b->level_chain)
+	if (b == current_binding_level)
+	  break;
+      if (b)
+	b = class_binding_level;
+      else
+	b = current_binding_level;
+    }
+  else
+    b = current_binding_level;
+  print_other_binding_stack (b);
+  fprintf (stderr, "global:\n");
+  print_binding_level (NAMESPACE_LEVEL (global_namespace));
+}
+
+/* Return the type associated with ID.  */
 
-	  *newval = oldval;
-	  for (tmp = decls.value; tmp; tmp = OVL_NEXT (tmp))
-	    {
-	      tree new_fn = OVL_CURRENT (tmp);
+static tree
+identifier_type_value_1 (tree id)
+{
+  /* There is no type with that name, anywhere.  */
+  if (REAL_IDENTIFIER_TYPE_VALUE (id) == NULL_TREE)
+    return NULL_TREE;
+  /* This is not the type marker, but the real thing.  */
+  if (REAL_IDENTIFIER_TYPE_VALUE (id) != global_type_node)
+    return REAL_IDENTIFIER_TYPE_VALUE (id);
+  /* Have to search for it. It must be on the global level, now.
+     Ask lookup_name not to return non-types.  */
+  id = lookup_name_real (id, 2, 1, /*block_p=*/true, 0, 0);
+  if (id)
+    return TREE_TYPE (id);
+  return NULL_TREE;
+}
 
-	      /* Don't import functions that haven't been declared.  */
-	      if (DECL_ANTICIPATED (new_fn))
-		continue;
+/* Wrapper for identifier_type_value_1.  */
 
-	      /* [namespace.udecl]
+tree
+identifier_type_value (tree id)
+{
+  tree ret;
+  timevar_start (TV_NAME_LOOKUP);
+  ret = identifier_type_value_1 (id);
+  timevar_stop (TV_NAME_LOOKUP);
+  return ret;
+}
 
-		 If a function declaration in namespace scope or block
-		 scope has the same name and the same parameter types as a
-		 function introduced by a using declaration the program is
-		 ill-formed.  */
-	      for (tmp1 = oldval; tmp1; tmp1 = OVL_NEXT (tmp1))
-		{
-		  tree old_fn = OVL_CURRENT (tmp1);
 
-		  if (new_fn == old_fn)
-		    /* The function already exists in the current namespace.  */
-		    break;
-		  else if (TREE_CODE (tmp1) == OVERLOAD && OVL_USED (tmp1))
-		    continue; /* this is a using decl */
-		  else if (compparms_for_decl_and_using_decl (new_fn, old_fn))
-		    {
-		      /* There was already a non-using declaration in
-			 this scope with the same parameter types. If both
-			 are the same extern "C" functions, that's ok.  */
-		      if (DECL_ANTICIPATED (old_fn)
-			  && !DECL_HIDDEN_FRIEND_P (old_fn))
-			/* Ignore anticipated built-ins.  */;
-		      else if (decls_match (new_fn, old_fn))
-			break;
-		      else
-			{
-			  diagnose_name_conflict (new_fn, old_fn);
-			  break;
-			}
-		    }
-		}
+/* Return the IDENTIFIER_GLOBAL_VALUE of T, for use in common code, since
+   the definition of IDENTIFIER_GLOBAL_VALUE is different for C and C++.  */
 
-	      /* If we broke out of the loop, there's no reason to add
-		 this function to the using declarations for this
-		 scope.  */
-	      if (tmp1)
-		continue;
+tree
+identifier_global_value	(tree t)
+{
+  return IDENTIFIER_GLOBAL_VALUE (t);
+}
 
-	      /* If we are adding to an existing OVERLOAD, then we no
-		 longer know the type of the set of functions.  */
-	      if (*newval && TREE_CODE (*newval) == OVERLOAD)
-		TREE_TYPE (*newval) = unknown_type_node;
-	      /* Add this new function to the set.  */
-	      *newval = build_overload (OVL_CURRENT (tmp), *newval);
-	      /* If there is only one function, then we use its type.  (A
-		 using-declaration naming a single function can be used in
-		 contexts where overload resolution cannot be
-		 performed.)  */
-	      if (TREE_CODE (*newval) != OVERLOAD)
-		{
-		  *newval = ovl_cons (*newval, NULL_TREE);
-		  TREE_TYPE (*newval) = TREE_TYPE (OVL_CURRENT (tmp));
-		}
-	      OVL_USED (*newval) = 1;
-	    }
-	}
-      else
-	{
-	  /* If we're declaring a non-function and OLDVAL is an anticipated
-	     built-in, just pretend it isn't there.  */
-	  if (oldval
-	      && TREE_CODE (oldval) == FUNCTION_DECL
-	      && DECL_ANTICIPATED (oldval)
-	      && !DECL_HIDDEN_FRIEND_P (oldval))
-	    oldval = NULL_TREE;
+/* Push a definition of struct, union or enum tag named ID.  into
+   binding_level B.  DECL is a TYPE_DECL for the type.  We assume that
+   the tag ID is not already defined.  */
 
-	  *newval = decls.value;
-	  if (oldval && !decls_match (*newval, oldval))
-	    error ("%qD is already declared in this scope", name);
-	}
-    }
-  else
-    *newval = oldval;
+static void
+set_identifier_type_value_with_scope (tree id, tree decl, cp_binding_level *b)
+{
+  tree type;
 
-  if (decls.type && TREE_CODE (decls.type) == TREE_LIST)
+  if (b->kind != sk_namespace)
     {
-      error ("reference to %qD is ambiguous", name);
-      print_candidates (decls.type);
+      /* Shadow the marker, not the real thing, so that the marker
+	 gets restored later.  */
+      tree old_type_value = REAL_IDENTIFIER_TYPE_VALUE (id);
+      b->type_shadowed
+	= tree_cons (id, old_type_value, b->type_shadowed);
+      type = decl ? TREE_TYPE (decl) : NULL_TREE;
+      TREE_TYPE (b->type_shadowed) = type;
     }
   else
     {
-      *newtype = decls.type;
-      if (oldtype && *newtype && !decls_match (oldtype, *newtype))
-	error ("%qD is already declared in this scope", name);
-    }
+      cxx_binding *binding =
+	binding_for_name (NAMESPACE_LEVEL (current_namespace), id);
+      gcc_assert (decl);
+      if (binding->value)
+	supplement_binding (binding, decl);
+      else
+	binding->value = decl;
 
-    /* If *newval is empty, shift any class or enumeration name down.  */
-    if (!*newval)
-      {
-	*newval = *newtype;
-	*newtype = NULL_TREE;
-      }
+      /* Store marker instead of real type.  */
+      type = global_type_node;
+    }
+  SET_IDENTIFIER_TYPE_VALUE (id, type);
 }
 
-/* Process a using-declaration at function scope.  */
+/* As set_identifier_type_value_with_scope, but using
+   current_binding_level.  */
 
 void
-do_local_using_decl (tree decl, tree scope, tree name)
+set_identifier_type_value (tree id, tree decl)
 {
-  tree oldval, oldtype, newval, newtype;
-  tree orig_decl = decl;
+  set_identifier_type_value_with_scope (id, decl, current_binding_level);
+}
 
-  decl = validate_nonmember_using_decl (decl, scope, name);
-  if (decl == NULL_TREE)
-    return;
+/* Return the name for the constructor (or destructor) for the
+   specified class TYPE.  When given a template, this routine doesn't
+   lose the specialization.  */
 
-  if (building_stmt_list_p ()
-      && at_function_scope_p ())
-    add_decl_expr (decl);
+static inline tree
+constructor_name_full (tree type)
+{
+  return TYPE_IDENTIFIER (TYPE_MAIN_VARIANT (type));
+}
 
-  oldval = lookup_name_innermost_nonclass_level (name);
-  oldtype = lookup_type_current_level (name);
+/* Return the name for the constructor (or destructor) for the
+   specified class.  When given a template, return the plain
+   unspecialized name.  */
 
-  do_nonmember_using_decl (scope, name, oldval, oldtype, &newval, &newtype);
+tree
+constructor_name (tree type)
+{
+  tree name;
+  name = constructor_name_full (type);
+  if (IDENTIFIER_TEMPLATE (name))
+    name = IDENTIFIER_TEMPLATE (name);
+  return name;
+}
 
-  if (newval)
-    {
-      if (is_overloaded_fn (newval))
-	{
-	  tree fn, term;
+/* Returns TRUE if NAME is the name for the constructor for TYPE,
+   which must be a class type.  */
 
-	  /* We only need to push declarations for those functions
-	     that were not already bound in the current level.
-	     The old value might be NULL_TREE, it might be a single
-	     function, or an OVERLOAD.  */
-	  if (oldval && TREE_CODE (oldval) == OVERLOAD)
-	    term = OVL_FUNCTION (oldval);
-	  else
-	    term = oldval;
-	  for (fn = newval; fn && OVL_CURRENT (fn) != term;
-	       fn = OVL_NEXT (fn))
-	    push_overloaded_decl (OVL_CURRENT (fn),
-				  PUSH_LOCAL | PUSH_USING,
-				  false);
-	}
-      else
-	push_local_binding (name, newval, PUSH_USING);
-    }
-  if (newtype)
-    {
-      push_local_binding (name, newtype, PUSH_USING);
-      set_identifier_type_value (name, newtype);
-    }
+bool
+constructor_name_p (tree name, tree type)
+{
+  tree ctor_name;
 
-  /* Emit debug info.  */
-  if (!processing_template_decl)
-    cp_emit_debug_info_for_using (orig_decl, current_scope());
+  gcc_assert (MAYBE_CLASS_TYPE_P (type));
+
+  if (!name)
+    return false;
+
+  if (!identifier_p (name))
+    return false;
+
+  /* These don't have names.  */
+  if (TREE_CODE (type) == DECLTYPE_TYPE
+      || TREE_CODE (type) == TYPEOF_TYPE)
+    return false;
+
+  ctor_name = constructor_name_full (type);
+  if (name == ctor_name)
+    return true;
+  if (IDENTIFIER_TEMPLATE (ctor_name)
+      && name == IDENTIFIER_TEMPLATE (ctor_name))
+    return true;
+  return false;
 }
 
-/* Returns true if ROOT (a namespace, class, or function) encloses
-   CHILD.  CHILD may be either a class type or a namespace.  */
+/* Counter used to create anonymous type names.  */
 
-bool
-is_ancestor (tree root, tree child)
+static GTY(()) int anon_cnt;
+
+/* Return an IDENTIFIER which can be used as a name for
+   unnamed structs and unions.  */
+
+tree
+make_anon_name (void)
 {
-  gcc_assert ((TREE_CODE (root) == NAMESPACE_DECL
-	       || TREE_CODE (root) == FUNCTION_DECL
-	       || CLASS_TYPE_P (root)));
-  gcc_assert ((TREE_CODE (child) == NAMESPACE_DECL
-	       || CLASS_TYPE_P (child)));
+  char buf[32];
+
+  sprintf (buf, anon_aggrname_format (), anon_cnt++);
+  return get_identifier (buf);
+}
+
+/* This code is practically identical to that for creating
+   anonymous names, but is just used for lambdas instead.  This isn't really
+   necessary, but it's convenient to avoid treating lambdas like other
+   unnamed types.  */
+
+static GTY(()) int lambda_cnt = 0;
+
+tree
+make_lambda_name (void)
+{
+  char buf[32];
+
+  sprintf (buf, LAMBDANAME_FORMAT, lambda_cnt++);
+  return get_identifier (buf);
+}
 
-  /* The global namespace encloses everything.  */
-  if (root == global_namespace)
-    return true;
+/* Return (from the stack of) the BINDING, if any, established at SCOPE.  */
 
-  while (true)
-    {
-      /* If we've run out of scopes, stop.  */
-      if (!child)
-	return false;
-      /* If we've reached the ROOT, it encloses CHILD.  */
-      if (root == child)
-	return true;
-      /* Go out one level.  */
-      if (TYPE_P (child))
-	child = TYPE_NAME (child);
-      child = DECL_CONTEXT (child);
-    }
+static inline cxx_binding *
+find_binding (cp_binding_level *scope, cxx_binding *binding)
+{
+  for (; binding != NULL; binding = binding->previous)
+    if (binding->scope == scope)
+      return binding;
+
+  return (cxx_binding *)0;
 }
 
-/* Enter the class or namespace scope indicated by T suitable for name
-   lookup.  T can be arbitrary scope, not necessary nested inside the
-   current scope.  Returns a non-null scope to pop iff pop_scope
-   should be called later to exit this scope.  */
+/* Return the binding for NAME in SCOPE, if any.  Otherwise, return NULL.  */
 
-tree
-push_scope (tree t)
+static inline cxx_binding *
+cp_binding_level_find_binding_for_name (cp_binding_level *scope, tree name)
 {
-  if (TREE_CODE (t) == NAMESPACE_DECL)
-    push_decl_namespace (t);
-  else if (CLASS_TYPE_P (t))
+  cxx_binding *b = IDENTIFIER_NAMESPACE_BINDINGS (name);
+  if (b)
     {
-      if (!at_class_scope_p ()
-	  || !same_type_p (current_class_type, t))
-	push_nested_class (t);
-      else
-	/* T is the same as the current scope.  There is therefore no
-	   need to re-enter the scope.  Since we are not actually
-	   pushing a new scope, our caller should not call
-	   pop_scope.  */
-	t = NULL_TREE;
+      /* Fold-in case where NAME is used only once.  */
+      if (scope == b->scope && b->previous == NULL)
+	return b;
+      return find_binding (scope, b);
     }
-
-  return t;
+  return NULL;
 }
 
-/* Leave scope pushed by push_scope.  */
+/* Always returns a binding for name in scope.  If no binding is
+   found, make a new one.  */
 
-void
-pop_scope (tree t)
+static cxx_binding *
+binding_for_name (cp_binding_level *scope, tree name)
 {
-  if (t == NULL_TREE)
-    return;
-  if (TREE_CODE (t) == NAMESPACE_DECL)
-    pop_decl_namespace ();
-  else if CLASS_TYPE_P (t)
-    pop_nested_class ();
-}
+  cxx_binding *result;
 
-/* Subroutine of push_inner_scope.  */
+  result = cp_binding_level_find_binding_for_name (scope, name);
+  if (result)
+    return result;
+  /* Not found, make a new one.  */
+  result = cxx_binding_make (NULL, NULL);
+  result->previous = IDENTIFIER_NAMESPACE_BINDINGS (name);
+  result->scope = scope;
+  result->is_local = false;
+  result->value_is_inherited = false;
+  IDENTIFIER_NAMESPACE_BINDINGS (name) = result;
+  return result;
+}
 
-static void
-push_inner_scope_r (tree outer, tree inner)
+/* Walk through the bindings associated to the name of FUNCTION,
+   and return the first declaration of a function with a
+   "C" linkage specification, a.k.a 'extern "C"'.
+   This function looks for the binding, regardless of which scope it
+   has been defined in. It basically looks in all the known scopes.
+   Note that this function does not lookup for bindings of builtin functions
+   or for functions declared in system headers.  */
+static tree
+lookup_extern_c_fun_in_all_ns (tree function)
 {
-  tree prev;
+  tree name;
+  cxx_binding *iter;
 
-  if (outer == inner
-      || (TREE_CODE (inner) != NAMESPACE_DECL && !CLASS_TYPE_P (inner)))
-    return;
+  gcc_assert (function && TREE_CODE (function) == FUNCTION_DECL);
 
-  prev = CP_DECL_CONTEXT (TREE_CODE (inner) == NAMESPACE_DECL ? inner : TYPE_NAME (inner));
-  if (outer != prev)
-    push_inner_scope_r (outer, prev);
-  if (TREE_CODE (inner) == NAMESPACE_DECL)
+  name = DECL_NAME (function);
+  gcc_assert (name && identifier_p (name));
+
+  for (iter = IDENTIFIER_NAMESPACE_BINDINGS (name);
+       iter;
+       iter = iter->previous)
     {
-      cp_binding_level *save_template_parm = 0;
-      /* Temporary take out template parameter scopes.  They are saved
-	 in reversed order in save_template_parm.  */
-      while (current_binding_level->kind == sk_template_parms)
+      tree ovl;
+      for (ovl = iter->value; ovl; ovl = OVL_NEXT (ovl))
 	{
-	  cp_binding_level *b = current_binding_level;
-	  current_binding_level = b->level_chain;
-	  b->level_chain = save_template_parm;
-	  save_template_parm = b;
+	  tree decl = OVL_CURRENT (ovl);
+	  if (decl
+	      && TREE_CODE (decl) == FUNCTION_DECL
+	      && DECL_EXTERN_C_P (decl)
+	      && !DECL_ARTIFICIAL (decl))
+	    {
+	      return decl;
+	    }
 	}
+    }
+  return NULL;
+}
 
-      resume_scope (NAMESPACE_LEVEL (inner));
-      current_namespace = inner;
+/* Returns a list of C-linkage decls with the name NAME.  */
 
-      /* Restore template parameter scopes.  */
-      while (save_template_parm)
+tree
+c_linkage_bindings (tree name)
+{
+  tree decls = NULL_TREE;
+  cxx_binding *iter;
+
+  for (iter = IDENTIFIER_NAMESPACE_BINDINGS (name);
+       iter;
+       iter = iter->previous)
+    {
+      tree ovl;
+      for (ovl = iter->value; ovl; ovl = OVL_NEXT (ovl))
 	{
-	  cp_binding_level *b = save_template_parm;
-	  save_template_parm = b->level_chain;
-	  b->level_chain = current_binding_level;
-	  current_binding_level = b;
+	  tree decl = OVL_CURRENT (ovl);
+	  if (decl
+	      && DECL_EXTERN_C_P (decl)
+	      && !DECL_ARTIFICIAL (decl))
+	    {
+	      if (decls == NULL_TREE)
+		decls = decl;
+	      else
+		decls = tree_cons (NULL_TREE, decl, decls);
+	    }
 	}
     }
-  else
-    pushclass (inner);
+  return decls;
 }
 
-/* Enter the scope INNER from current scope.  INNER must be a scope
-   nested inside current scope.  This works with both name lookup and
-   pushing name into scope.  In case a template parameter scope is present,
-   namespace is pushed under the template parameter scope according to
-   name lookup rule in 14.6.1/6.
-
-   Return the former current scope suitable for pop_inner_scope.  */
+/* Insert another USING_DECL into the current binding level, returning
+   this declaration. If this is a redeclaration, do nothing, and
+   return NULL_TREE if this not in namespace scope (in namespace
+   scope, a using decl might extend any previous bindings).  */
 
-tree
-push_inner_scope (tree inner)
+static tree
+push_using_decl_1 (tree scope, tree name)
 {
-  tree outer = current_scope ();
-  if (!outer)
-    outer = current_namespace;
+  tree decl;
 
-  push_inner_scope_r (outer, inner);
-  return outer;
+  gcc_assert (TREE_CODE (scope) == NAMESPACE_DECL);
+  gcc_assert (identifier_p (name));
+  for (decl = current_binding_level->usings; decl; decl = DECL_CHAIN (decl))
+    if (USING_DECL_SCOPE (decl) == scope && DECL_NAME (decl) == name)
+      break;
+  if (decl)
+    return namespace_bindings_p () ? decl : NULL_TREE;
+  decl = build_lang_decl (USING_DECL, name, NULL_TREE);
+  USING_DECL_SCOPE (decl) = scope;
+  DECL_CHAIN (decl) = current_binding_level->usings;
+  current_binding_level->usings = decl;
+  return decl;
 }
 
-/* Exit the current scope INNER back to scope OUTER.  */
+/* Wrapper for push_using_decl_1.  */
 
-void
-pop_inner_scope (tree outer, tree inner)
+static tree
+push_using_decl (tree scope, tree name)
 {
-  if (outer == inner
-      || (TREE_CODE (inner) != NAMESPACE_DECL && !CLASS_TYPE_P (inner)))
-    return;
+  tree ret;
+  timevar_start (TV_NAME_LOOKUP);
+  ret = push_using_decl_1 (scope, name);
+  timevar_stop (TV_NAME_LOOKUP);
+  return ret;
+}
 
-  while (outer != inner)
-    {
-      if (TREE_CODE (inner) == NAMESPACE_DECL)
-	{
-	  cp_binding_level *save_template_parm = 0;
-	  /* Temporary take out template parameter scopes.  They are saved
-	     in reversed order in save_template_parm.  */
-	  while (current_binding_level->kind == sk_template_parms)
-	    {
-	      cp_binding_level *b = current_binding_level;
-	      current_binding_level = b->level_chain;
-	      b->level_chain = save_template_parm;
-	      save_template_parm = b;
-	    }
+/* Same as pushdecl, but define X in binding-level LEVEL.  We rely on the
+   caller to set DECL_CONTEXT properly.
 
-	  pop_namespace ();
+   Note that this must only be used when X will be the new innermost
+   binding for its name, as we tack it onto the front of IDENTIFIER_BINDING
+   without checking to see if the current IDENTIFIER_BINDING comes from a
+   closer binding level than LEVEL.  */
 
-	  /* Restore template parameter scopes.  */
-	  while (save_template_parm)
-	    {
-	      cp_binding_level *b = save_template_parm;
-	      save_template_parm = b->level_chain;
-	      b->level_chain = current_binding_level;
-	      current_binding_level = b;
-	    }
-	}
-      else
-	popclass ();
+static tree
+pushdecl_with_scope_1 (tree x, cp_binding_level *level, bool is_friend)
+{
+  cp_binding_level *b;
+  tree function_decl = current_function_decl;
 
-      inner = CP_DECL_CONTEXT (TREE_CODE (inner) == NAMESPACE_DECL ? inner : TYPE_NAME (inner));
+  current_function_decl = NULL_TREE;
+  if (level->kind == sk_class)
+    {
+      b = class_binding_level;
+      class_binding_level = level;
+      pushdecl_class_level (x);
+      class_binding_level = b;
+    }
+  else
+    {
+      b = current_binding_level;
+      current_binding_level = level;
+      x = pushdecl_maybe_friend (x, is_friend);
+      current_binding_level = b;
     }
+  current_function_decl = function_decl;
+  return x;
 }
-
-/* Do a pushlevel for class declarations.  */
+ 
+/* Wrapper for pushdecl_with_scope_1.  */
 
-void
-pushlevel_class (void)
+tree
+pushdecl_with_scope (tree x, cp_binding_level *level, bool is_friend)
 {
-  class_binding_level = begin_scope (sk_class, current_class_type);
+  tree ret;
+  bool subtime = timevar_cond_start (TV_NAME_LOOKUP);
+  ret = pushdecl_with_scope_1 (x, level, is_friend);
+  timevar_cond_stop (TV_NAME_LOOKUP, subtime);
+  return ret;
 }
 
-/* ...and a poplevel for class declarations.  */
+/* Helper function for push_overloaded_decl_1 and do_nonmember_using_decl.
+   Compares the parameter-type-lists of DECL1 and DECL2 and returns false
+   if they are different.  If the DECLs are template functions, the return
+   types and the template parameter lists are compared too (DR 565).  */
 
-void
-poplevel_class (void)
+static bool
+compparms_for_decl_and_using_decl (tree decl1, tree decl2)
 {
-  cp_binding_level *level = class_binding_level;
-  cp_class_binding *cb;
-  size_t i;
-  tree shadowed;
-
-  bool subtime = timevar_cond_start (TV_NAME_LOOKUP);
-  gcc_assert (level != 0);
-
-  /* If we're leaving a toplevel class, cache its binding level.  */
-  if (current_class_depth == 1)
-    previous_class_level = level;
-  for (shadowed = level->type_shadowed;
-       shadowed;
-       shadowed = TREE_CHAIN (shadowed))
-    SET_IDENTIFIER_TYPE_VALUE (TREE_PURPOSE (shadowed), TREE_VALUE (shadowed));
+  if (!compparms (TYPE_ARG_TYPES (TREE_TYPE (decl1)),
+		  TYPE_ARG_TYPES (TREE_TYPE (decl2))))
+    return false;
 
-  /* Remove the bindings for all of the class-level declarations.  */
-  if (level->class_shadowed)
-    {
-      FOR_EACH_VEC_ELT (*level->class_shadowed, i, cb)
-	{
-	  IDENTIFIER_BINDING (cb->identifier) = cb->base->previous;
-	  cxx_binding_free (cb->base);
-	}
-      ggc_free (level->class_shadowed);
-      level->class_shadowed = NULL;
-    }
+  if (! DECL_FUNCTION_TEMPLATE_P (decl1)
+      || ! DECL_FUNCTION_TEMPLATE_P (decl2))
+    return true;
 
-  /* Now, pop out of the binding level which we created up in the
-     `pushlevel_class' routine.  */
-  gcc_assert (current_binding_level == level);
-  leave_scope ();
-  timevar_cond_stop (TV_NAME_LOOKUP, subtime);
+  return (comp_template_parms (DECL_TEMPLATE_PARMS (decl1),
+			       DECL_TEMPLATE_PARMS (decl2))
+	  && same_type_p (TREE_TYPE (TREE_TYPE (decl1)),
+			  TREE_TYPE (TREE_TYPE (decl2))));
 }
 
-/* Set INHERITED_VALUE_BINDING_P on BINDING to true or false, as
-   appropriate.  DECL is the value to which a name has just been
-   bound.  CLASS_TYPE is the class in which the lookup occurred.  */
+/* DECL is a FUNCTION_DECL for a non-member function, which may have
+   other definitions already in place.  We get around this by making
+   the value of the identifier point to a list of all the things that
+   want to be referenced by that name.  It is then up to the users of
+   that name to decide what to do with that list.
 
-static void
-set_inherited_value_binding_p (cxx_binding *binding, tree decl,
-			       tree class_type)
-{
-  if (binding->value == decl && TREE_CODE (decl) != TREE_LIST)
-    {
-      tree context;
+   DECL may also be a TEMPLATE_DECL, with a FUNCTION_DECL in its
+   DECL_TEMPLATE_RESULT.  It is dealt with the same way.
 
-      if (TREE_CODE (decl) == OVERLOAD)
-	context = ovl_scope (decl);
-      else
-	{
-	  gcc_assert (DECL_P (decl));
-	  context = context_for_name_lookup (decl);
-	}
+   FLAGS is a bitwise-or of the following values:
+     PUSH_LOCAL: Bind DECL in the current scope, rather than at
+		 namespace scope.
+     PUSH_USING: DECL is being pushed as the result of a using
+		 declaration.
 
-      if (is_properly_derived_from (class_type, context))
-	INHERITED_VALUE_BINDING_P (binding) = 1;
-      else
-	INHERITED_VALUE_BINDING_P (binding) = 0;
-    }
-  else if (binding->value == decl)
-    /* We only encounter a TREE_LIST when there is an ambiguity in the
-       base classes.  Such an ambiguity can be overridden by a
-       definition in this class.  */
-    INHERITED_VALUE_BINDING_P (binding) = 1;
-  else
-    INHERITED_VALUE_BINDING_P (binding) = 0;
-}
+   IS_FRIEND is true if this is a friend declaration.
 
-/* Make the declaration of X appear in CLASS scope.  */
+   The value returned may be a previous declaration if we guessed wrong
+   about what language DECL should belong to (C or C++).  Otherwise,
+   it's always DECL (and never something that's not a _DECL).  */
 
-bool
-pushdecl_class_level (tree x)
+static tree
+push_overloaded_decl_1 (tree decl, int flags, bool is_friend)
 {
-  tree name;
-  bool is_valid = true;
-  bool subtime;
-
-  /* Do nothing if we're adding to an outer lambda closure type,
-     outer_binding will add it later if it's needed.  */
-  if (current_class_type != class_binding_level->this_entity)
-    return true;
+  tree name = DECL_NAME (decl);
+  tree old;
+  tree new_binding;
+  int doing_global = (namespace_bindings_p () || !(flags & PUSH_LOCAL));
 
-  subtime = timevar_cond_start (TV_NAME_LOOKUP);
-  /* Get the name of X.  */
-  if (TREE_CODE (x) == OVERLOAD)
-    name = DECL_NAME (get_first_fn (x));
+  if (doing_global)
+    old = namespace_binding (name, DECL_CONTEXT (decl));
   else
-    name = DECL_NAME (x);
+    old = lookup_name_innermost_nonclass_level (name);
 
-  if (name)
-    {
-      is_valid = push_class_level_binding (name, x);
-      if (TREE_CODE (x) == TYPE_DECL)
-	set_identifier_type_value (name, x);
-    }
-  else if (ANON_AGGR_TYPE_P (TREE_TYPE (x)))
+  if (old)
     {
-      /* If X is an anonymous aggregate, all of its members are
-	 treated as if they were members of the class containing the
-	 aggregate, for naming purposes.  */
-      tree f;
-
-      for (f = TYPE_FIELDS (TREE_TYPE (x)); f; f = DECL_CHAIN (f))
+      if (TREE_CODE (old) == TYPE_DECL && DECL_ARTIFICIAL (old))
 	{
-	  location_t save_location = input_location;
-	  input_location = DECL_SOURCE_LOCATION (f);
-	  if (!pushdecl_class_level (f))
-	    is_valid = false;
-	  input_location = save_location;
+	  tree t = TREE_TYPE (old);
+	  if (MAYBE_CLASS_TYPE_P (t) && warn_shadow
+	      && (! DECL_IN_SYSTEM_HEADER (decl)
+		  || ! DECL_IN_SYSTEM_HEADER (old)))
+	    warning (OPT_Wshadow, "%q#D hides constructor for %q#T", decl, t);
+	  old = NULL_TREE;
 	}
-    }
-  timevar_cond_stop (TV_NAME_LOOKUP, subtime);
-  return is_valid;
-}
-
-/* Return the BINDING (if any) for NAME in SCOPE, which is a class
-   scope.  If the value returned is non-NULL, and the PREVIOUS field
-   is not set, callers must set the PREVIOUS field explicitly.  */
+      else if (is_overloaded_fn (old))
+	{
+	  tree tmp;
 
-static cxx_binding *
-get_class_binding (tree name, cp_binding_level *scope)
-{
-  tree class_type;
-  tree type_binding;
-  tree value_binding;
-  cxx_binding *binding;
+	  for (tmp = old; tmp; tmp = OVL_NEXT (tmp))
+	    {
+	      tree fn = OVL_CURRENT (tmp);
+	      tree dup;
 
-  class_type = scope->this_entity;
+	      if (TREE_CODE (tmp) == OVERLOAD && OVL_USED (tmp)
+		  && !(flags & PUSH_USING)
+		  && compparms_for_decl_and_using_decl (fn, decl)
+		  && ! decls_match (fn, decl))
+		diagnose_name_conflict (decl, fn);
 
-  /* Get the type binding.  */
-  type_binding = lookup_member (class_type, name,
-				/*protect=*/2, /*want_type=*/true,
-				tf_warning_or_error);
-  /* Get the value binding.  */
-  value_binding = lookup_member (class_type, name,
-				 /*protect=*/2, /*want_type=*/false,
-				 tf_warning_or_error);
+	      dup = duplicate_decls (decl, fn, is_friend);
+	      /* If DECL was a redeclaration of FN -- even an invalid
+		 one -- pass that information along to our caller.  */
+	      if (dup == fn || dup == error_mark_node)
+		return dup;
+	    }
 
-  if (value_binding
-      && (TREE_CODE (value_binding) == TYPE_DECL
-	  || DECL_CLASS_TEMPLATE_P (value_binding)
-	  || (TREE_CODE (value_binding) == TREE_LIST
-	      && TREE_TYPE (value_binding) == error_mark_node
-	      && (TREE_CODE (TREE_VALUE (value_binding))
-		  == TYPE_DECL))))
-    /* We found a type binding, even when looking for a non-type
-       binding.  This means that we already processed this binding
-       above.  */
-    ;
-  else if (value_binding)
-    {
-      if (TREE_CODE (value_binding) == TREE_LIST
-	  && TREE_TYPE (value_binding) == error_mark_node)
-	/* NAME is ambiguous.  */
-	;
-      else if (BASELINK_P (value_binding))
-	/* NAME is some overloaded functions.  */
-	value_binding = BASELINK_FUNCTIONS (value_binding);
+	  /* We don't overload implicit built-ins.  duplicate_decls()
+	     may fail to merge the decls if the new decl is e.g. a
+	     template function.  */
+	  if (TREE_CODE (old) == FUNCTION_DECL
+	      && DECL_ANTICIPATED (old)
+	      && !DECL_HIDDEN_FRIEND_P (old))
+	    old = NULL;
+	}
+      else if (old == error_mark_node)
+	/* Ignore the undefined symbol marker.  */
+	old = NULL_TREE;
+      else
+	{
+	  error ("previous non-function declaration %q+#D", old);
+	  error ("conflicts with function declaration %q#D", decl);
+	  return decl;
+	}
     }
 
-  /* If we found either a type binding or a value binding, create a
-     new binding object.  */
-  if (type_binding || value_binding)
+  if (old || TREE_CODE (decl) == TEMPLATE_DECL
+      /* If it's a using declaration, we always need to build an OVERLOAD,
+	 because it's the only way to remember that the declaration comes
+	 from 'using', and have the lookup behave correctly.  */
+      || (flags & PUSH_USING))
     {
-      binding = new_class_binding (name,
-				   value_binding,
-				   type_binding,
-				   scope);
-      /* This is a class-scope binding, not a block-scope binding.  */
-      LOCAL_BINDING_P (binding) = 0;
-      set_inherited_value_binding_p (binding, value_binding, class_type);
+      if (old && TREE_CODE (old) != OVERLOAD)
+	/* Wrap the existing single decl in an overload.  */
+	new_binding = ovl_cons (old, NULL_TREE);
+      else
+	new_binding = old;
+      new_binding = ovl_cons (decl, new_binding);
+      if (flags & PUSH_USING)
+	OVL_USED (new_binding) = 1;
     }
   else
-    binding = NULL;
-
-  return binding;
-}
-
-/* Make the declaration(s) of X appear in CLASS scope under the name
-   NAME.  Returns true if the binding is valid.  */
-
-static bool
-push_class_level_binding_1 (tree name, tree x)
-{
-  cxx_binding *binding;
-  tree decl = x;
-  bool ok;
-
-  /* The class_binding_level will be NULL if x is a template
-     parameter name in a member template.  */
-  if (!class_binding_level)
-    return true;
-
-  if (name == error_mark_node)
-    return false;
+    /* NAME is not ambiguous.  */
+    new_binding = decl;
 
-  /* Can happen for an erroneous declaration (c++/60384).  */
-  if (!identifier_p (name))
+  if (doing_global)
+    set_namespace_binding (name, current_namespace, new_binding);
+  else
     {
-      gcc_assert (errorcount || sorrycount);
-      return false;
-    }
+      /* We only create an OVERLOAD if there was a previous binding at
+	 this level, or if decl is a template. In the former case, we
+	 need to remove the old binding and replace it with the new
+	 binding.  We must also run through the NAMES on the binding
+	 level where the name was bound to update the chain.  */
 
-  /* Check for invalid member names.  But don't worry about a default
-     argument-scope lambda being pushed after the class is complete.  */
-  gcc_assert (TYPE_BEING_DEFINED (current_class_type)
-	      || LAMBDA_TYPE_P (TREE_TYPE (decl)));
-  /* Check that we're pushing into the right binding level.  */
-  gcc_assert (current_class_type == class_binding_level->this_entity);
+      if (TREE_CODE (new_binding) == OVERLOAD && old)
+	{
+	  tree *d;
 
-  /* We could have been passed a tree list if this is an ambiguous
-     declaration. If so, pull the declaration out because
-     check_template_shadow will not handle a TREE_LIST.  */
-  if (TREE_CODE (decl) == TREE_LIST
-      && TREE_TYPE (decl) == error_mark_node)
-    decl = TREE_VALUE (decl);
+	  for (d = &IDENTIFIER_BINDING (name)->scope->names;
+	       *d;
+	       d = &TREE_CHAIN (*d))
+	    if (*d == old
+		|| (TREE_CODE (*d) == TREE_LIST
+		    && TREE_VALUE (*d) == old))
+	      {
+		if (TREE_CODE (*d) == TREE_LIST)
+		  /* Just replace the old binding with the new.  */
+		  TREE_VALUE (*d) = new_binding;
+		else
+		  /* Build a TREE_LIST to wrap the OVERLOAD.  */
+		  *d = tree_cons (NULL_TREE, new_binding,
+				  TREE_CHAIN (*d));
 
-  if (!check_template_shadow (decl))
-    return false;
+		/* And update the cxx_binding node.  */
+		IDENTIFIER_BINDING (name)->value = new_binding;
+		return decl;
+	      }
 
-  /* [class.mem]
+	  /* We should always find a previous binding in this case.  */
+	  gcc_unreachable ();
+	}
 
-     If T is the name of a class, then each of the following shall
-     have a name different from T:
+      /* Install the new binding.  */
+      push_local_binding (name, new_binding, flags);
+    }
 
-     -- every static data member of class T;
+  return decl;
+}
 
-     -- every member of class T that is itself a type;
+/* Wrapper for push_overloaded_decl_1.  */
 
-     -- every enumerator of every member of class T that is an
-	enumerated type;
+static tree
+push_overloaded_decl (tree decl, int flags, bool is_friend)
+{
+  tree ret;
+  bool subtime = timevar_cond_start (TV_NAME_LOOKUP);
+  ret = push_overloaded_decl_1 (decl, flags, is_friend);
+  timevar_cond_stop (TV_NAME_LOOKUP, subtime);
+  return ret;
+}
 
-     -- every member of every anonymous union that is a member of
-	class T.
+/* Check a non-member using-declaration. Return the name and scope
+   being used, and the USING_DECL, or NULL_TREE on failure.  */
 
-     (Non-static data members were also forbidden to have the same
-     name as T until TC1.)  */
-  if ((VAR_P (x)
-       || TREE_CODE (x) == CONST_DECL
-       || (TREE_CODE (x) == TYPE_DECL
-	   && !DECL_SELF_REFERENCE_P (x))
-       /* A data member of an anonymous union.  */
-       || (TREE_CODE (x) == FIELD_DECL
-	   && DECL_CONTEXT (x) != current_class_type))
-      && DECL_NAME (x) == constructor_name (current_class_type))
+static tree
+validate_nonmember_using_decl (tree decl, tree scope, tree name)
+{
+  /* [namespace.udecl]
+       A using-declaration for a class member shall be a
+       member-declaration.  */
+  if (TYPE_P (scope))
     {
-      tree scope = context_for_name_lookup (x);
-      if (TYPE_P (scope) && same_type_p (scope, current_class_type))
-	{
-	  error ("%qD has the same name as the class in which it is "
-		 "declared",
-		 x);
-	  return false;
-	}
+      error ("%qT is not a namespace or unscoped enum", scope);
+      return NULL_TREE;
     }
+  else if (scope == error_mark_node)
+    return NULL_TREE;
 
-  /* Get the current binding for NAME in this class, if any.  */
-  binding = IDENTIFIER_BINDING (name);
-  if (!binding || binding->scope != class_binding_level)
+  if (TREE_CODE (decl) == TEMPLATE_ID_EXPR)
     {
-      binding = get_class_binding (name, class_binding_level);
-      /* If a new binding was created, put it at the front of the
-	 IDENTIFIER_BINDING list.  */
-      if (binding)
-	{
-	  binding->previous = IDENTIFIER_BINDING (name);
-	  IDENTIFIER_BINDING (name) = binding;
-	}
+      /* 7.3.3/5
+	   A using-declaration shall not name a template-id.  */
+      error ("a using-declaration cannot specify a template-id.  "
+	     "Try %<using %D%>", name);
+      return NULL_TREE;
     }
 
-  /* If there is already a binding, then we may need to update the
-     current value.  */
-  if (binding && binding->value)
+  if (TREE_CODE (decl) == NAMESPACE_DECL)
     {
-      tree bval = binding->value;
-      tree old_decl = NULL_TREE;
-      tree target_decl = strip_using_decl (decl);
-      tree target_bval = strip_using_decl (bval);
-
-      if (INHERITED_VALUE_BINDING_P (binding))
-	{
-	  /* If the old binding was from a base class, and was for a
-	     tag name, slide it over to make room for the new binding.
-	     The old binding is still visible if explicitly qualified
-	     with a class-key.  */
-	  if (TREE_CODE (target_bval) == TYPE_DECL
-	      && DECL_ARTIFICIAL (target_bval)
-	      && !(TREE_CODE (target_decl) == TYPE_DECL
-		   && DECL_ARTIFICIAL (target_decl)))
-	    {
-	      old_decl = binding->type;
-	      binding->type = bval;
-	      binding->value = NULL_TREE;
-	      INHERITED_VALUE_BINDING_P (binding) = 0;
-	    }
-	  else
-	    {
-	      old_decl = bval;
-	      /* Any inherited type declaration is hidden by the type
-		 declaration in the derived class.  */
-	      if (TREE_CODE (target_decl) == TYPE_DECL
-		  && DECL_ARTIFICIAL (target_decl))
-		binding->type = NULL_TREE;
-	    }
-	}
-      else if (TREE_CODE (target_decl) == OVERLOAD
-	       && is_overloaded_fn (target_bval))
-	old_decl = bval;
-      else if (TREE_CODE (decl) == USING_DECL
-	       && TREE_CODE (bval) == USING_DECL
-	       && same_type_p (USING_DECL_SCOPE (decl),
-			       USING_DECL_SCOPE (bval)))
-	/* This is a using redeclaration that will be diagnosed later
-	   in supplement_binding */
-	;
-      else if (TREE_CODE (decl) == USING_DECL
-	       && TREE_CODE (bval) == USING_DECL
-	       && DECL_DEPENDENT_P (decl)
-	       && DECL_DEPENDENT_P (bval))
-	return true;
-      else if (TREE_CODE (decl) == USING_DECL
-	       && is_overloaded_fn (target_bval))
-	old_decl = bval;
-      else if (TREE_CODE (bval) == USING_DECL
-	       && is_overloaded_fn (target_decl))
-	return true;
-
-      if (old_decl && binding->scope == class_binding_level)
-	{
-	  binding->value = x;
-	  /* It is always safe to clear INHERITED_VALUE_BINDING_P
-	     here.  This function is only used to register bindings
-	     from with the class definition itself.  */
-	  INHERITED_VALUE_BINDING_P (binding) = 0;
-	  return true;
-	}
+      error ("namespace %qD not allowed in using-declaration", decl);
+      return NULL_TREE;
     }
 
-  /* Note that we declared this value so that we can issue an error if
-     this is an invalid redeclaration of a name already used for some
-     other purpose.  */
-  note_name_declared_in_class (name, decl);
-
-  /* If we didn't replace an existing binding, put the binding on the
-     stack of bindings for the identifier, and update the shadowed
-     list.  */
-  if (binding && binding->scope == class_binding_level)
-    /* Supplement the existing binding.  */
-    ok = supplement_binding (binding, decl);
-  else
+  if (TREE_CODE (decl) == SCOPE_REF)
     {
-      /* Create a new binding.  */
-      push_binding (name, decl, class_binding_level);
-      ok = true;
+      /* It's a nested name with template parameter dependent scope.
+	 This can only be using-declaration for class member.  */
+      error ("%qT is not a namespace", TREE_OPERAND (decl, 0));
+      return NULL_TREE;
     }
 
-  return ok;
-}
+  if (is_overloaded_fn (decl))
+    decl = get_first_fn (decl);
+
+  gcc_assert (DECL_P (decl));
 
-/* Wrapper for push_class_level_binding_1.  */
+  /* Make a USING_DECL.  */
+  tree using_decl = push_using_decl (scope, name);
 
-bool
-push_class_level_binding (tree name, tree x)
-{
-  bool ret;
-  bool subtime = timevar_cond_start (TV_NAME_LOOKUP);
-  ret = push_class_level_binding_1 (name, x);
-  timevar_cond_stop (TV_NAME_LOOKUP, subtime);
-  return ret;
+  if (using_decl == NULL_TREE
+      && at_function_scope_p ()
+      && VAR_P (decl))
+    /* C++11 7.3.3/10.  */
+    error ("%qD is already declared in this scope", name);
+  
+  return using_decl;
 }
 
-/* Process "using SCOPE::NAME" in a class scope.  Return the
-   USING_DECL created.  */
+/* Process local and global using-declarations.  */
 
-tree
-do_class_using_decl (tree scope, tree name)
+static void
+do_nonmember_using_decl (tree scope, tree name, tree oldval, tree oldtype,
+			 tree *newval, tree *newtype)
 {
-  /* The USING_DECL returned by this function.  */
-  tree value;
-  /* The declaration (or declarations) name by this using
-     declaration.  NULL if we are in a template and cannot figure out
-     what has been named.  */
-  tree decl;
-  /* True if SCOPE is a dependent type.  */
-  bool scope_dependent_p;
-  /* True if SCOPE::NAME is dependent.  */
-  bool name_dependent_p;
-  /* True if any of the bases of CURRENT_CLASS_TYPE are dependent.  */
-  bool bases_dependent_p;
-  tree binfo;
+  struct scope_binding decls = EMPTY_SCOPE_BINDING;
 
-  if (name == error_mark_node)
-    return NULL_TREE;
+  *newval = *newtype = NULL_TREE;
+  if (!qualified_lookup_using_namespace (name, scope, &decls, 0))
+    /* Lookup error */
+    return;
 
-  if (!scope || !TYPE_P (scope))
+  if (!decls.value && !decls.type)
     {
-      error ("using-declaration for non-member at class scope");
-      return NULL_TREE;
+      error ("%qD not declared", name);
+      return;
     }
 
-  /* Make sure the name is not invalid */
-  if (TREE_CODE (name) == BIT_NOT_EXPR)
+  /* Shift the old and new bindings around so we're comparing class and
+     enumeration names to each other.  */
+  if (oldval && DECL_IMPLICIT_TYPEDEF_P (oldval))
     {
-      error ("%<%T::%D%> names destructor", scope, name);
-      return NULL_TREE;
+      oldtype = oldval;
+      oldval = NULL_TREE;
     }
-  /* Using T::T declares inheriting ctors, even if T is a typedef.  */
-  if (MAYBE_CLASS_TYPE_P (scope)
-      && (name == TYPE_IDENTIFIER (scope)
-	  || constructor_name_p (name, scope)))
+
+  if (decls.value && DECL_IMPLICIT_TYPEDEF_P (decls.value))
     {
-      maybe_warn_cpp0x (CPP0X_INHERITING_CTORS);
-      name = ctor_identifier;
-      CLASSTYPE_NON_AGGREGATE (current_class_type) = true;
+      decls.type = decls.value;
+      decls.value = NULL_TREE;
     }
-  if (constructor_name_p (name, current_class_type))
+
+  if (decls.value)
     {
-      error ("%<%T::%D%> names constructor in %qT",
-	     scope, name, current_class_type);
-      return NULL_TREE;
-    }
+      /* Check for using functions.  */
+      if (is_overloaded_fn (decls.value))
+	{
+	  tree tmp, tmp1;
 
-  scope_dependent_p = dependent_scope_p (scope);
-  name_dependent_p = (scope_dependent_p
-		      || (IDENTIFIER_TYPENAME_P (name)
-			  && dependent_type_p (TREE_TYPE (name))));
+	  if (oldval && !is_overloaded_fn (oldval))
+	    {
+	      error ("%qD is already declared in this scope", name);
+	      oldval = NULL_TREE;
+	    }
 
-  bases_dependent_p = any_dependent_bases_p ();
+	  *newval = oldval;
+	  for (tmp = decls.value; tmp; tmp = OVL_NEXT (tmp))
+	    {
+	      tree new_fn = OVL_CURRENT (tmp);
 
-  decl = NULL_TREE;
+	      /* Don't import functions that haven't been declared.  */
+	      if (DECL_ANTICIPATED (new_fn))
+		continue;
 
-  /* From [namespace.udecl]:
+	      /* [namespace.udecl]
 
-       A using-declaration used as a member-declaration shall refer to a
-       member of a base class of the class being defined.
+		 If a function declaration in namespace scope or block
+		 scope has the same name and the same parameter types as a
+		 function introduced by a using declaration the program is
+		 ill-formed.  */
+	      for (tmp1 = oldval; tmp1; tmp1 = OVL_NEXT (tmp1))
+		{
+		  tree old_fn = OVL_CURRENT (tmp1);
 
-     In general, we cannot check this constraint in a template because
-     we do not know the entire set of base classes of the current
-     class type. Morover, if SCOPE is dependent, it might match a
-     non-dependent base.  */
+		  if (new_fn == old_fn)
+		    /* The function already exists in the current namespace.  */
+		    break;
+		  else if (TREE_CODE (tmp1) == OVERLOAD && OVL_USED (tmp1))
+		    continue; /* this is a using decl */
+		  else if (compparms_for_decl_and_using_decl (new_fn, old_fn))
+		    {
+		      /* There was already a non-using declaration in
+			 this scope with the same parameter types. If both
+			 are the same extern "C" functions, that's ok.  */
+		      if (DECL_ANTICIPATED (old_fn)
+			  && !DECL_HIDDEN_FRIEND_P (old_fn))
+			/* Ignore anticipated built-ins.  */;
+		      else if (decls_match (new_fn, old_fn))
+			break;
+		      else
+			{
+			  diagnose_name_conflict (new_fn, old_fn);
+			  break;
+			}
+		    }
+		}
 
-  if (!scope_dependent_p)
-    {
-      base_kind b_kind;
-      binfo = lookup_base (current_class_type, scope, ba_any, &b_kind,
-			   tf_warning_or_error);
-      if (b_kind < bk_proper_base)
-	{
-	  if (!bases_dependent_p || b_kind == bk_same_type)
-	    {
-	      error_not_base_type (scope, current_class_type);
-	      return NULL_TREE;
+	      /* If we broke out of the loop, there's no reason to add
+		 this function to the using declarations for this
+		 scope.  */
+	      if (tmp1)
+		continue;
+
+	      /* If we are adding to an existing OVERLOAD, then we no
+		 longer know the type of the set of functions.  */
+	      if (*newval && TREE_CODE (*newval) == OVERLOAD)
+		TREE_TYPE (*newval) = unknown_type_node;
+	      /* Add this new function to the set.  */
+	      *newval = build_overload (OVL_CURRENT (tmp), *newval);
+	      /* If there is only one function, then we use its type.  (A
+		 using-declaration naming a single function can be used in
+		 contexts where overload resolution cannot be
+		 performed.)  */
+	      if (TREE_CODE (*newval) != OVERLOAD)
+		{
+		  *newval = ovl_cons (*newval, NULL_TREE);
+		  TREE_TYPE (*newval) = TREE_TYPE (OVL_CURRENT (tmp));
+		}
+	      OVL_USED (*newval) = 1;
 	    }
 	}
-      else if (name == ctor_identifier
-	       && BINFO_INHERITANCE_CHAIN (BINFO_INHERITANCE_CHAIN (binfo)))
+      else
 	{
-	  error ("cannot inherit constructors from indirect base %qT", scope);
-	  return NULL_TREE;
+	  /* If we're declaring a non-function and OLDVAL is an anticipated
+	     built-in, just pretend it isn't there.  */
+	  if (oldval
+	      && TREE_CODE (oldval) == FUNCTION_DECL
+	      && DECL_ANTICIPATED (oldval)
+	      && !DECL_HIDDEN_FRIEND_P (oldval))
+	    oldval = NULL_TREE;
+
+	  *newval = decls.value;
+	  if (oldval && !decls_match (*newval, oldval))
+	    error ("%qD is already declared in this scope", name);
 	}
-      else if (!name_dependent_p)
+    }
+  else
+    *newval = oldval;
+
+  if (decls.type && TREE_CODE (decls.type) == TREE_LIST)
+    {
+      error ("reference to %qD is ambiguous", name);
+      print_candidates (decls.type);
+    }
+  else
+    {
+      *newtype = decls.type;
+      if (oldtype && *newtype && !decls_match (oldtype, *newtype))
+	error ("%qD is already declared in this scope", name);
+    }
+
+    /* If *newval is empty, shift any class or enumeration name down.  */
+    if (!*newval)
+      {
+	*newval = *newtype;
+	*newtype = NULL_TREE;
+      }
+}
+
+/* Process a using-declaration at function scope.  */
+
+void
+do_local_using_decl (tree decl, tree scope, tree name)
+{
+  tree oldval, oldtype, newval, newtype;
+  tree orig_decl = decl;
+
+  decl = validate_nonmember_using_decl (decl, scope, name);
+  if (decl == NULL_TREE)
+    return;
+
+  if (building_stmt_list_p ()
+      && at_function_scope_p ())
+    add_decl_expr (decl);
+
+  oldval = lookup_name_innermost_nonclass_level (name);
+  oldtype = lookup_type_current_level (name);
+
+  do_nonmember_using_decl (scope, name, oldval, oldtype, &newval, &newtype);
+
+  if (newval)
+    {
+      if (is_overloaded_fn (newval))
 	{
-	  decl = lookup_member (binfo, name, 0, false, tf_warning_or_error);
-	  if (!decl)
-	    {
-	      error ("no members matching %<%T::%D%> in %q#T", scope, name,
-		     scope);
-	      return NULL_TREE;
-	    }
-	  /* The binfo from which the functions came does not matter.  */
-	  if (BASELINK_P (decl))
-	    decl = BASELINK_FUNCTIONS (decl);
+	  tree fn, term;
+
+	  /* We only need to push declarations for those functions
+	     that were not already bound in the current level.
+	     The old value might be NULL_TREE, it might be a single
+	     function, or an OVERLOAD.  */
+	  if (oldval && TREE_CODE (oldval) == OVERLOAD)
+	    term = OVL_FUNCTION (oldval);
+	  else
+	    term = oldval;
+	  for (fn = newval; fn && OVL_CURRENT (fn) != term;
+	       fn = OVL_NEXT (fn))
+	    push_overloaded_decl (OVL_CURRENT (fn),
+				  PUSH_LOCAL | PUSH_USING,
+				  false);
 	}
+      else
+	push_local_binding (name, newval, PUSH_USING);
+    }
+  if (newtype)
+    {
+      push_local_binding (name, newtype, PUSH_USING);
+      set_identifier_type_value (name, newtype);
     }
 
-  value = build_lang_decl (USING_DECL, name, NULL_TREE);
-  USING_DECL_DECLS (value) = decl;
-  USING_DECL_SCOPE (value) = scope;
-  DECL_DEPENDENT_P (value) = !decl;
-
-  return value;
+  /* Emit debug info.  */
+  if (!processing_template_decl)
+    cp_emit_debug_info_for_using (orig_decl, current_scope());
 }
 
-
-/* Return the binding value for name in scope.  */
-
+/* Returns true if ROOT (a namespace, class, or function) encloses
+   CHILD.  CHILD may be either a class type or a namespace.  */
 
-static tree
-namespace_binding_1 (tree name, tree scope)
+bool
+is_ancestor (tree root, tree child)
 {
-  cxx_binding *binding;
-
-  if (SCOPE_FILE_SCOPE_P (scope))
-    scope = global_namespace;
-  else
-    /* Unnecessary for the global namespace because it can't be an alias. */
-    scope = ORIGINAL_NAMESPACE (scope);
-
-  binding = cp_binding_level_find_binding_for_name (NAMESPACE_LEVEL (scope), name);
+  gcc_assert ((TREE_CODE (root) == NAMESPACE_DECL
+	       || TREE_CODE (root) == FUNCTION_DECL
+	       || CLASS_TYPE_P (root)));
+  gcc_assert ((TREE_CODE (child) == NAMESPACE_DECL
+	       || CLASS_TYPE_P (child)));
 
-  return binding ? binding->value : NULL_TREE;
-}
+  /* The global namespace encloses everything.  */
+  if (root == global_namespace)
+    return true;
 
-tree
-namespace_binding (tree name, tree scope)
-{
-  tree ret;
-  bool subtime = timevar_cond_start (TV_NAME_LOOKUP);
-  ret = namespace_binding_1 (name, scope);
-  timevar_cond_stop (TV_NAME_LOOKUP, subtime);
-  return ret;
+  while (true)
+    {
+      /* If we've run out of scopes, stop.  */
+      if (!child)
+	return false;
+      /* If we've reached the ROOT, it encloses CHILD.  */
+      if (root == child)
+	return true;
+      /* Go out one level.  */
+      if (TYPE_P (child))
+	child = TYPE_NAME (child);
+      child = DECL_CONTEXT (child);
+    }
 }
 
-/* Set the binding value for name in scope.  */
+/* Enter the class or namespace scope indicated by T suitable for name
+   lookup.  T can be arbitrary scope, not necessary nested inside the
+   current scope.  Returns a non-null scope to pop iff pop_scope
+   should be called later to exit this scope.  */
 
-static void
-set_namespace_binding_1 (tree name, tree scope, tree val)
+tree
+push_scope (tree t)
 {
-  cxx_binding *b;
+  if (TREE_CODE (t) == NAMESPACE_DECL)
+    push_decl_namespace (t);
+  else if (CLASS_TYPE_P (t))
+    {
+      if (!at_class_scope_p ()
+	  || !same_type_p (current_class_type, t))
+	push_nested_class (t);
+      else
+	/* T is the same as the current scope.  There is therefore no
+	   need to re-enter the scope.  Since we are not actually
+	   pushing a new scope, our caller should not call
+	   pop_scope.  */
+	t = NULL_TREE;
+    }
 
-  if (scope == NULL_TREE)
-    scope = global_namespace;
-  b = binding_for_name (NAMESPACE_LEVEL (scope), name);
-  if (!b->value
-      /* For templates and using we create a single element OVERLOAD.
-	 Look for the chain to know whether this is really augmenting
-	 an existing overload.  */
-      || (TREE_CODE (val) == OVERLOAD && OVL_CHAIN (val))
-      || val == error_mark_node)
-    b->value = val;
-  else
-    supplement_binding (b, val);
+  return t;
 }
 
-/* Wrapper for set_namespace_binding_1.  */
+/* Leave scope pushed by push_scope.  */
 
 void
-set_namespace_binding (tree name, tree scope, tree val)
+pop_scope (tree t)
 {
-  bool subtime = timevar_cond_start (TV_NAME_LOOKUP);
-  set_namespace_binding_1 (name, scope, val);
-  timevar_cond_stop (TV_NAME_LOOKUP, subtime);
+  if (t == NULL_TREE)
+    return;
+  if (TREE_CODE (t) == NAMESPACE_DECL)
+    pop_decl_namespace ();
+  else if CLASS_TYPE_P (t)
+    pop_nested_class ();
 }
 
-/* Set the context of a declaration to scope. Complain if we are not
-   outside scope.  */
+/* Subroutine of push_inner_scope.  */
 
-void
-set_decl_namespace (tree decl, tree scope, bool friendp)
+static void
+push_inner_scope_r (tree outer, tree inner)
 {
-  tree old;
-
-  /* Get rid of namespace aliases.  */
-  scope = ORIGINAL_NAMESPACE (scope);
-
-  /* It is ok for friends to be qualified in parallel space.  */
-  if (!friendp && !is_ancestor (current_namespace, scope))
-    error ("declaration of %qD not in a namespace surrounding %qD",
-	   decl, scope);
-  DECL_CONTEXT (decl) = FROB_CONTEXT (scope);
-
-  /* Writing "int N::i" to declare a variable within "N" is invalid.  */
-  if (scope == current_namespace)
-    {
-      if (at_namespace_scope_p ())
-	error ("explicit qualification in declaration of %qD",
-	       decl);
-      return;
-    }
+  tree prev;
 
-  /* See whether this has been declared in the namespace.  */
-  old = lookup_qualified_name (scope, DECL_NAME (decl), /*type*/false,
-			       /*complain*/true, /*hidden*/true);
-  if (old == error_mark_node)
-    /* No old declaration at all.  */
-    goto complain;
-  /* If it's a TREE_LIST, the result of the lookup was ambiguous.  */
-  if (TREE_CODE (old) == TREE_LIST)
-    {
-      error ("reference to %qD is ambiguous", decl);
-      print_candidates (old);
-      return;
-    }
-  if (!is_overloaded_fn (decl))
-    {
-      /* We might have found OLD in an inline namespace inside SCOPE.  */
-      if (TREE_CODE (decl) == TREE_CODE (old))
-	DECL_CONTEXT (decl) = DECL_CONTEXT (old);
-      /* Don't compare non-function decls with decls_match here, since
-	 it can't check for the correct constness at this
-	 point. pushdecl will find those errors later.  */
-      return;
-    }
-  /* Since decl is a function, old should contain a function decl.  */
-  if (!is_overloaded_fn (old))
-    goto complain;
-  /* We handle these in check_explicit_instantiation_namespace.  */
-  if (processing_explicit_instantiation)
-    return;
-  if (processing_template_decl || processing_specialization)
-    /* We have not yet called push_template_decl to turn a
-       FUNCTION_DECL into a TEMPLATE_DECL, so the declarations won't
-       match.  But, we'll check later, when we construct the
-       template.  */
-    return;
-  /* Instantiations or specializations of templates may be declared as
-     friends in any namespace.  */
-  if (friendp && DECL_USE_TEMPLATE (decl))
+  if (outer == inner
+      || (TREE_CODE (inner) != NAMESPACE_DECL && !CLASS_TYPE_P (inner)))
     return;
-  if (is_overloaded_fn (old))
+
+  prev = CP_DECL_CONTEXT (TREE_CODE (inner) == NAMESPACE_DECL ? inner : TYPE_NAME (inner));
+  if (outer != prev)
+    push_inner_scope_r (outer, prev);
+  if (TREE_CODE (inner) == NAMESPACE_DECL)
     {
-      tree found = NULL_TREE;
-      tree elt = old;
-      for (; elt; elt = OVL_NEXT (elt))
+      cp_binding_level *save_template_parm = 0;
+      /* Temporary take out template parameter scopes.  They are saved
+	 in reversed order in save_template_parm.  */
+      while (current_binding_level->kind == sk_template_parms)
 	{
-	  tree ofn = OVL_CURRENT (elt);
-	  /* Adjust DECL_CONTEXT first so decls_match will return true
-	     if DECL will match a declaration in an inline namespace.  */
-	  DECL_CONTEXT (decl) = DECL_CONTEXT (ofn);
-	  if (decls_match (decl, ofn))
-	    {
-	      if (found && !decls_match (found, ofn))
-		{
-		  DECL_CONTEXT (decl) = FROB_CONTEXT (scope);
-		  error ("reference to %qD is ambiguous", decl);
-		  print_candidates (old);
-		  return;
-		}
-	      found = ofn;
-	    }
+	  cp_binding_level *b = current_binding_level;
+	  current_binding_level = b->level_chain;
+	  b->level_chain = save_template_parm;
+	  save_template_parm = b;
 	}
-      if (found)
+
+      resume_scope (NAMESPACE_LEVEL (inner));
+      current_namespace = inner;
+
+      /* Restore template parameter scopes.  */
+      while (save_template_parm)
 	{
-	  if (!is_associated_namespace (scope, CP_DECL_CONTEXT (found)))
-	    goto complain;
-	  if (DECL_HIDDEN_FRIEND_P (found))
-	    {
-	      pedwarn (DECL_SOURCE_LOCATION (decl), 0,
-		       "%qD has not been declared within %D", decl, scope);
-	      inform (DECL_SOURCE_LOCATION (found), "only here as a friend");
-	    }
-	  DECL_CONTEXT (decl) = DECL_CONTEXT (found);
-	  return;
+	  cp_binding_level *b = save_template_parm;
+	  save_template_parm = b->level_chain;
+	  b->level_chain = current_binding_level;
+	  current_binding_level = b;
 	}
     }
-  else
-    {
-      DECL_CONTEXT (decl) = DECL_CONTEXT (old);
-      if (decls_match (decl, old))
-	return;
-    }
-
-  /* It didn't work, go back to the explicit scope.  */
-  DECL_CONTEXT (decl) = FROB_CONTEXT (scope);
- complain:
-  error ("%qD should have been declared inside %qD", decl, scope);
+  else
+    pushclass (inner);
 }
 
-/* Return the namespace where the current declaration is declared.  */
+/* Enter the scope INNER from current scope.  INNER must be a scope
+   nested inside current scope.  This works with both name lookup and
+   pushing name into scope.  In case a template parameter scope is present,
+   namespace is pushed under the template parameter scope according to
+   name lookup rule in 14.6.1/6.
+
+   Return the former current scope suitable for pop_inner_scope.  */
 
 tree
-current_decl_namespace (void)
+push_inner_scope (tree inner)
 {
-  tree result;
-  /* If we have been pushed into a different namespace, use it.  */
-  if (!vec_safe_is_empty (decl_namespace_list))
-    return decl_namespace_list->last ();
+  tree outer = current_scope ();
+  if (!outer)
+    outer = current_namespace;
 
-  if (current_class_type)
-    result = decl_namespace_context (current_class_type);
-  else if (current_function_decl)
-    result = decl_namespace_context (current_function_decl);
-  else
-    result = current_namespace;
-  return result;
+  push_inner_scope_r (outer, inner);
+  return outer;
 }
 
-/* Process any ATTRIBUTES on a namespace definition.  Returns true if
-   attribute visibility is seen.  */
+/* Exit the current scope INNER back to scope OUTER.  */
 
-bool
-handle_namespace_attrs (tree ns, tree attributes)
+void
+pop_inner_scope (tree outer, tree inner)
 {
-  tree d;
-  bool saw_vis = false;
+  if (outer == inner
+      || (TREE_CODE (inner) != NAMESPACE_DECL && !CLASS_TYPE_P (inner)))
+    return;
 
-  for (d = attributes; d; d = TREE_CHAIN (d))
+  while (outer != inner)
     {
-      tree name = get_attribute_name (d);
-      tree args = TREE_VALUE (d);
-
-      if (is_attribute_p ("visibility", name))
+      if (TREE_CODE (inner) == NAMESPACE_DECL)
 	{
-	  /* attribute visibility is a property of the syntactic block
-	     rather than the namespace as a whole, so we don't touch the
-	     NAMESPACE_DECL at all.  */
-	  tree x = args ? TREE_VALUE (args) : NULL_TREE;
-	  if (x == NULL_TREE || TREE_CODE (x) != STRING_CST || TREE_CHAIN (args))
+	  cp_binding_level *save_template_parm = 0;
+	  /* Temporary take out template parameter scopes.  They are saved
+	     in reversed order in save_template_parm.  */
+	  while (current_binding_level->kind == sk_template_parms)
 	    {
-	      warning (OPT_Wattributes,
-		       "%qD attribute requires a single NTBS argument",
-		       name);
-	      continue;
+	      cp_binding_level *b = current_binding_level;
+	      current_binding_level = b->level_chain;
+	      b->level_chain = save_template_parm;
+	      save_template_parm = b;
 	    }
 
-	  if (!TREE_PUBLIC (ns))
-	    warning (OPT_Wattributes,
-		     "%qD attribute is meaningless since members of the "
-		     "anonymous namespace get local symbols", name);
+	  pop_namespace ();
 
-	  push_visibility (TREE_STRING_POINTER (x), 1);
-	  saw_vis = true;
-	}
-      else if (is_attribute_p ("abi_tag", name))
-	{
-	  if (!DECL_NAMESPACE_ASSOCIATIONS (ns))
-	    {
-	      warning (OPT_Wattributes, "ignoring %qD attribute on non-inline "
-		       "namespace", name);
-	      continue;
-	    }
-	  if (!DECL_NAME (ns))
-	    {
-	      warning (OPT_Wattributes, "ignoring %qD attribute on anonymous "
-		       "namespace", name);
-	      continue;
-	    }
-	  if (!args)
+	  /* Restore template parameter scopes.  */
+	  while (save_template_parm)
 	    {
-	      tree dn = DECL_NAME (ns);
-	      args = build_string (IDENTIFIER_LENGTH (dn) + 1,
-				   IDENTIFIER_POINTER (dn));
-	      TREE_TYPE (args) = char_array_type_node;
-	      args = fix_string_type (args);
-	      args = build_tree_list (NULL_TREE, args);
+	      cp_binding_level *b = save_template_parm;
+	      save_template_parm = b->level_chain;
+	      b->level_chain = current_binding_level;
+	      current_binding_level = b;
 	    }
-	  if (check_abi_tag_args (args, name))
-	    DECL_ATTRIBUTES (ns) = tree_cons (name, args,
-					      DECL_ATTRIBUTES (ns));
 	}
       else
-	{
-	  warning (OPT_Wattributes, "%qD attribute directive ignored",
-		   name);
-	  continue;
-	}
+	popclass ();
+
+      inner = CP_DECL_CONTEXT (TREE_CODE (inner) == NAMESPACE_DECL ? inner : TYPE_NAME (inner));
     }
+}
+
+/* Do a pushlevel for class declarations.  */
 
-  return saw_vis;
+void
+pushlevel_class (void)
+{
+  class_binding_level = begin_scope (sk_class, current_class_type);
 }
-  
-/* Push into the scope of the NAME namespace.  If NAME is NULL_TREE, then we
-   select a name that is unique to this compilation unit.  Returns FALSE if
-   pushdecl fails, TRUE otherwise.  */
 
-bool
-push_namespace (tree name)
+/* ...and a poplevel for class declarations.  */
+
+void
+poplevel_class (void)
 {
-  tree d = NULL_TREE;
-  bool need_new = true;
-  bool implicit_use = false;
-  bool anon = !name;
+  cp_binding_level *level = class_binding_level;
+  cp_class_binding *cb;
+  size_t i;
+  tree shadowed;
 
   bool subtime = timevar_cond_start (TV_NAME_LOOKUP);
+  gcc_assert (level != 0);
 
-  /* We should not get here if the global_namespace is not yet constructed
-     nor if NAME designates the global namespace:  The global scope is
-     constructed elsewhere.  */
-  gcc_assert (global_namespace != NULL && name != global_scope_name);
+  /* If we're leaving a toplevel class, cache its binding level.  */
+  if (current_class_depth == 1)
+    previous_class_level = level;
+  for (shadowed = level->type_shadowed;
+       shadowed;
+       shadowed = TREE_CHAIN (shadowed))
+    SET_IDENTIFIER_TYPE_VALUE (TREE_PURPOSE (shadowed), TREE_VALUE (shadowed));
 
-  if (anon)
-    {
-      name = get_anonymous_namespace_name();
-      d = IDENTIFIER_NAMESPACE_VALUE (name);
-      if (d)
-	/* Reopening anonymous namespace.  */
-	need_new = false;
-      implicit_use = true;
-    }
-  else
+  /* Remove the bindings for all of the class-level declarations.  */
+  if (level->class_shadowed)
     {
-      /* Check whether this is an extended namespace definition.  */
-      d = IDENTIFIER_NAMESPACE_VALUE (name);
-      if (d != NULL_TREE && TREE_CODE (d) == NAMESPACE_DECL)
+      FOR_EACH_VEC_ELT (*level->class_shadowed, i, cb)
 	{
-	  tree dna = DECL_NAMESPACE_ALIAS (d);
-	  if (dna)
- 	    {
-	      /* We do some error recovery for, eg, the redeclaration
-		 of M here:
-
-		 namespace N {}
-		 namespace M = N;
-		 namespace M {}
-
-		 However, in nasty cases like:
-
-		 namespace N
-		 {
-		   namespace M = N;
-		   namespace M {}
-		 }
-
-		 we just error out below, in duplicate_decls.  */
-	      if (NAMESPACE_LEVEL (dna)->level_chain
-		  == current_binding_level)
-		{
-		  error ("namespace alias %qD not allowed here, "
-			 "assuming %qD", d, dna);
-		  d = dna;
-		  need_new = false;
-		}
-	    }
-	  else
-	    need_new = false;
+	  IDENTIFIER_BINDING (cb->identifier) = cb->base->previous;
+	  cxx_binding_free (cb->base);
 	}
+      ggc_free (level->class_shadowed);
+      level->class_shadowed = NULL;
     }
 
-  if (need_new)
+  /* Now, pop out of the binding level which we created up in the
+     `pushlevel_class' routine.  */
+  gcc_assert (current_binding_level == level);
+  leave_scope ();
+  timevar_cond_stop (TV_NAME_LOOKUP, subtime);
+}
+
+/* Set INHERITED_VALUE_BINDING_P on BINDING to true or false, as
+   appropriate.  DECL is the value to which a name has just been
+   bound.  CLASS_TYPE is the class in which the lookup occurred.  */
+
+static void
+set_inherited_value_binding_p (cxx_binding *binding, tree decl,
+			       tree class_type)
+{
+  if (binding->value == decl && TREE_CODE (decl) != TREE_LIST)
     {
-      /* Make a new namespace, binding the name to it.  */
-      d = build_lang_decl (NAMESPACE_DECL, name, void_type_node);
-      DECL_CONTEXT (d) = FROB_CONTEXT (current_namespace);
-      /* The name of this namespace is not visible to other translation
-	 units if it is an anonymous namespace or member thereof.  */
-      if (anon || decl_anon_ns_mem_p (current_namespace))
-	TREE_PUBLIC (d) = 0;
+      tree context;
+
+      if (TREE_CODE (decl) == OVERLOAD)
+	context = ovl_scope (decl);
       else
-	TREE_PUBLIC (d) = 1;
-      if (pushdecl (d) == error_mark_node)
-	{
-	  timevar_cond_stop (TV_NAME_LOOKUP, subtime);
-	  return false;
-	}
-      if (anon)
 	{
-	  /* Clear DECL_NAME for the benefit of debugging back ends.  */
-	  SET_DECL_ASSEMBLER_NAME (d, name);
-	  DECL_NAME (d) = NULL_TREE;
+	  gcc_assert (DECL_P (decl));
+	  context = context_for_name_lookup (decl);
 	}
-      begin_scope (sk_namespace, d);
-    }
-  else
-    resume_scope (NAMESPACE_LEVEL (d));
-
-  if (implicit_use)
-    do_using_directive (d);
-  /* Enter the name space.  */
-  current_namespace = d;
 
-  timevar_cond_stop (TV_NAME_LOOKUP, subtime);
-  return true;
+      if (is_properly_derived_from (class_type, context))
+	INHERITED_VALUE_BINDING_P (binding) = 1;
+      else
+	INHERITED_VALUE_BINDING_P (binding) = 0;
+    }
+  else if (binding->value == decl)
+    /* We only encounter a TREE_LIST when there is an ambiguity in the
+       base classes.  Such an ambiguity can be overridden by a
+       definition in this class.  */
+    INHERITED_VALUE_BINDING_P (binding) = 1;
+  else
+    INHERITED_VALUE_BINDING_P (binding) = 0;
 }
 
-/* Pop from the scope of the current namespace.  */
+/* Make the declaration of X appear in CLASS scope.  */
 
-void
-pop_namespace (void)
+bool
+pushdecl_class_level (tree x)
 {
-  gcc_assert (current_namespace != global_namespace);
-  current_namespace = CP_DECL_CONTEXT (current_namespace);
-  /* The binding level is not popped, as it might be re-opened later.  */
-  leave_scope ();
-}
+  tree name;
+  bool is_valid = true;
+  bool subtime;
 
-/* Push into the scope of the namespace NS, even if it is deeply
-   nested within another namespace.  */
+  /* Do nothing if we're adding to an outer lambda closure type,
+     outer_binding will add it later if it's needed.  */
+  if (current_class_type != class_binding_level->this_entity)
+    return true;
 
-void
-push_nested_namespace (tree ns)
-{
-  if (ns == global_namespace)
-    push_to_top_level ();
+  subtime = timevar_cond_start (TV_NAME_LOOKUP);
+  /* Get the name of X.  */
+  if (TREE_CODE (x) == OVERLOAD)
+    name = DECL_NAME (get_first_fn (x));
   else
-    {
-      push_nested_namespace (CP_DECL_CONTEXT (ns));
-      push_namespace (DECL_NAME (ns));
-    }
-}
-
-/* Pop back from the scope of the namespace NS, which was previously
-   entered with push_nested_namespace.  */
+    name = DECL_NAME (x);
 
-void
-pop_nested_namespace (tree ns)
-{
-  bool subtime = timevar_cond_start (TV_NAME_LOOKUP);
-  gcc_assert (current_namespace == ns);
-  while (ns != global_namespace)
+  if (name)
     {
-      pop_namespace ();
-      ns = CP_DECL_CONTEXT (ns);
+      is_valid = push_class_level_binding (name, x);
+      if (TREE_CODE (x) == TYPE_DECL)
+	set_identifier_type_value (name, x);
     }
+  else if (ANON_AGGR_TYPE_P (TREE_TYPE (x)))
+    {
+      /* If X is an anonymous aggregate, all of its members are
+	 treated as if they were members of the class containing the
+	 aggregate, for naming purposes.  */
+      tree f;
 
-  pop_from_top_level ();
+      for (f = TYPE_FIELDS (TREE_TYPE (x)); f; f = DECL_CHAIN (f))
+	{
+	  location_t save_location = input_location;
+	  input_location = DECL_SOURCE_LOCATION (f);
+	  if (!pushdecl_class_level (f))
+	    is_valid = false;
+	  input_location = save_location;
+	}
+    }
   timevar_cond_stop (TV_NAME_LOOKUP, subtime);
+  return is_valid;
 }
 
-/* Temporarily set the namespace for the current declaration.  */
+/* Return the BINDING (if any) for NAME in SCOPE, which is a class
+   scope.  If the value returned is non-NULL, and the PREVIOUS field
+   is not set, callers must set the PREVIOUS field explicitly.  */
 
-void
-push_decl_namespace (tree decl)
+static cxx_binding *
+get_class_binding (tree name, cp_binding_level *scope)
 {
-  if (TREE_CODE (decl) != NAMESPACE_DECL)
-    decl = decl_namespace_context (decl);
-  vec_safe_push (decl_namespace_list, ORIGINAL_NAMESPACE (decl));
-}
+  tree class_type;
+  tree type_binding;
+  tree value_binding;
+  cxx_binding *binding;
 
-/* [namespace.memdef]/2 */
+  class_type = scope->this_entity;
 
-void
-pop_decl_namespace (void)
-{
-  decl_namespace_list->pop ();
-}
+  /* Get the type binding.  */
+  type_binding = lookup_member (class_type, name,
+				/*protect=*/2, /*want_type=*/true,
+				tf_warning_or_error);
+  /* Get the value binding.  */
+  value_binding = lookup_member (class_type, name,
+				 /*protect=*/2, /*want_type=*/false,
+				 tf_warning_or_error);
 
-/* Return the namespace that is the common ancestor
-   of two given namespaces.  */
+  if (value_binding
+      && (TREE_CODE (value_binding) == TYPE_DECL
+	  || DECL_CLASS_TEMPLATE_P (value_binding)
+	  || (TREE_CODE (value_binding) == TREE_LIST
+	      && TREE_TYPE (value_binding) == error_mark_node
+	      && (TREE_CODE (TREE_VALUE (value_binding))
+		  == TYPE_DECL))))
+    /* We found a type binding, even when looking for a non-type
+       binding.  This means that we already processed this binding
+       above.  */
+    ;
+  else if (value_binding)
+    {
+      if (TREE_CODE (value_binding) == TREE_LIST
+	  && TREE_TYPE (value_binding) == error_mark_node)
+	/* NAME is ambiguous.  */
+	;
+      else if (BASELINK_P (value_binding))
+	/* NAME is some overloaded functions.  */
+	value_binding = BASELINK_FUNCTIONS (value_binding);
+    }
 
-static tree
-namespace_ancestor_1 (tree ns1, tree ns2)
-{
-  tree nsr;
-  if (is_ancestor (ns1, ns2))
-    nsr = ns1;
+  /* If we found either a type binding or a value binding, create a
+     new binding object.  */
+  if (type_binding || value_binding)
+    {
+      binding = new_class_binding (name,
+				   value_binding,
+				   type_binding,
+				   scope);
+      /* This is a class-scope binding, not a block-scope binding.  */
+      LOCAL_BINDING_P (binding) = 0;
+      set_inherited_value_binding_p (binding, value_binding, class_type);
+    }
   else
-    nsr = namespace_ancestor_1 (CP_DECL_CONTEXT (ns1), ns2);
-  return nsr;
+    binding = NULL;
+
+  return binding;
 }
 
-/* Wrapper for namespace_ancestor_1.  */
+/* Make the declaration(s) of X appear in CLASS scope under the name
+   NAME.  Returns true if the binding is valid.  */
 
-static tree
-namespace_ancestor (tree ns1, tree ns2)
+static bool
+push_class_level_binding_1 (tree name, tree x)
 {
-  tree nsr;
-  bool subtime = timevar_cond_start (TV_NAME_LOOKUP);
-  nsr = namespace_ancestor_1 (ns1, ns2);
-  timevar_cond_stop (TV_NAME_LOOKUP, subtime);
-  return nsr;
-}
+  cxx_binding *binding;
+  tree decl = x;
+  bool ok;
 
-/* Process a namespace-alias declaration.  */
+  /* The class_binding_level will be NULL if x is a template
+     parameter name in a member template.  */
+  if (!class_binding_level)
+    return true;
 
-void
-do_namespace_alias (tree alias, tree name_space)
-{
-  if (name_space == error_mark_node)
-    return;
+  if (name == error_mark_node)
+    return false;
 
-  gcc_assert (TREE_CODE (name_space) == NAMESPACE_DECL);
+  /* Can happen for an erroneous declaration (c++/60384).  */
+  if (!identifier_p (name))
+    {
+      gcc_assert (errorcount || sorrycount);
+      return false;
+    }
 
-  name_space = ORIGINAL_NAMESPACE (name_space);
+  /* Check for invalid member names.  But don't worry about a default
+     argument-scope lambda being pushed after the class is complete.  */
+  gcc_assert (TYPE_BEING_DEFINED (current_class_type)
+	      || LAMBDA_TYPE_P (TREE_TYPE (decl)));
+  /* Check that we're pushing into the right binding level.  */
+  gcc_assert (current_class_type == class_binding_level->this_entity);
 
-  /* Build the alias.  */
-  alias = build_lang_decl (NAMESPACE_DECL, alias, void_type_node);
-  DECL_NAMESPACE_ALIAS (alias) = name_space;
-  DECL_EXTERNAL (alias) = 1;
-  DECL_CONTEXT (alias) = FROB_CONTEXT (current_scope ());
-  pushdecl (alias);
+  /* We could have been passed a tree list if this is an ambiguous
+     declaration. If so, pull the declaration out because
+     check_template_shadow will not handle a TREE_LIST.  */
+  if (TREE_CODE (decl) == TREE_LIST
+      && TREE_TYPE (decl) == error_mark_node)
+    decl = TREE_VALUE (decl);
 
-  /* Emit debug info for namespace alias.  */
-  if (!building_stmt_list_p ())
-    (*debug_hooks->early_global_decl) (alias);
-}
+  if (!check_template_shadow (decl))
+    return false;
 
-/* Like pushdecl, only it places X in the current namespace,
-   if appropriate.  */
+  /* [class.mem]
 
-tree
-pushdecl_namespace_level (tree x, bool is_friend)
-{
-  cp_binding_level *b = current_binding_level;
-  tree t;
+     If T is the name of a class, then each of the following shall
+     have a name different from T:
 
-  bool subtime = timevar_cond_start (TV_NAME_LOOKUP);
-  t = pushdecl_with_scope (x, NAMESPACE_LEVEL (current_namespace), is_friend);
+     -- every static data member of class T;
 
-  /* Now, the type_shadowed stack may screw us.  Munge it so it does
-     what we want.  */
-  if (TREE_CODE (t) == TYPE_DECL)
+     -- every member of class T that is itself a type;
+
+     -- every enumerator of every member of class T that is an
+	enumerated type;
+
+     -- every member of every anonymous union that is a member of
+	class T.
+
+     (Non-static data members were also forbidden to have the same
+     name as T until TC1.)  */
+  if ((VAR_P (x)
+       || TREE_CODE (x) == CONST_DECL
+       || (TREE_CODE (x) == TYPE_DECL
+	   && !DECL_SELF_REFERENCE_P (x))
+       /* A data member of an anonymous union.  */
+       || (TREE_CODE (x) == FIELD_DECL
+	   && DECL_CONTEXT (x) != current_class_type))
+      && DECL_NAME (x) == constructor_name (current_class_type))
+    {
+      tree scope = context_for_name_lookup (x);
+      if (TYPE_P (scope) && same_type_p (scope, current_class_type))
+	{
+	  error ("%qD has the same name as the class in which it is "
+		 "declared",
+		 x);
+	  return false;
+	}
+    }
+
+  /* Get the current binding for NAME in this class, if any.  */
+  binding = IDENTIFIER_BINDING (name);
+  if (!binding || binding->scope != class_binding_level)
     {
-      tree name = DECL_NAME (t);
-      tree newval;
-      tree *ptr = (tree *)0;
-      for (; !global_scope_p (b); b = b->level_chain)
+      binding = get_class_binding (name, class_binding_level);
+      /* If a new binding was created, put it at the front of the
+	 IDENTIFIER_BINDING list.  */
+      if (binding)
 	{
-	  tree shadowed = b->type_shadowed;
-	  for (; shadowed; shadowed = TREE_CHAIN (shadowed))
-	    if (TREE_PURPOSE (shadowed) == name)
-	      {
-		ptr = &TREE_VALUE (shadowed);
-		/* Can't break out of the loop here because sometimes
-		   a binding level will have duplicate bindings for
-		   PT names.  It's gross, but I haven't time to fix it.  */
-	      }
+	  binding->previous = IDENTIFIER_BINDING (name);
+	  IDENTIFIER_BINDING (name) = binding;
 	}
-      newval = TREE_TYPE (t);
-      if (ptr == (tree *)0)
+    }
+
+  /* If there is already a binding, then we may need to update the
+     current value.  */
+  if (binding && binding->value)
+    {
+      tree bval = binding->value;
+      tree old_decl = NULL_TREE;
+      tree target_decl = strip_using_decl (decl);
+      tree target_bval = strip_using_decl (bval);
+
+      if (INHERITED_VALUE_BINDING_P (binding))
 	{
-	  /* @@ This shouldn't be needed.  My test case "zstring.cc" trips
-	     up here if this is changed to an assertion.  --KR  */
-	  SET_IDENTIFIER_TYPE_VALUE (name, t);
+	  /* If the old binding was from a base class, and was for a
+	     tag name, slide it over to make room for the new binding.
+	     The old binding is still visible if explicitly qualified
+	     with a class-key.  */
+	  if (TREE_CODE (target_bval) == TYPE_DECL
+	      && DECL_ARTIFICIAL (target_bval)
+	      && !(TREE_CODE (target_decl) == TYPE_DECL
+		   && DECL_ARTIFICIAL (target_decl)))
+	    {
+	      old_decl = binding->type;
+	      binding->type = bval;
+	      binding->value = NULL_TREE;
+	      INHERITED_VALUE_BINDING_P (binding) = 0;
+	    }
+	  else
+	    {
+	      old_decl = bval;
+	      /* Any inherited type declaration is hidden by the type
+		 declaration in the derived class.  */
+	      if (TREE_CODE (target_decl) == TYPE_DECL
+		  && DECL_ARTIFICIAL (target_decl))
+		binding->type = NULL_TREE;
+	    }
 	}
-      else
+      else if (TREE_CODE (target_decl) == OVERLOAD
+	       && is_overloaded_fn (target_bval))
+	old_decl = bval;
+      else if (TREE_CODE (decl) == USING_DECL
+	       && TREE_CODE (bval) == USING_DECL
+	       && same_type_p (USING_DECL_SCOPE (decl),
+			       USING_DECL_SCOPE (bval)))
+	/* This is a using redeclaration that will be diagnosed later
+	   in supplement_binding */
+	;
+      else if (TREE_CODE (decl) == USING_DECL
+	       && TREE_CODE (bval) == USING_DECL
+	       && DECL_DEPENDENT_P (decl)
+	       && DECL_DEPENDENT_P (bval))
+	return true;
+      else if (TREE_CODE (decl) == USING_DECL
+	       && is_overloaded_fn (target_bval))
+	old_decl = bval;
+      else if (TREE_CODE (bval) == USING_DECL
+	       && is_overloaded_fn (target_decl))
+	return true;
+
+      if (old_decl && binding->scope == class_binding_level)
 	{
-	  *ptr = newval;
+	  binding->value = x;
+	  /* It is always safe to clear INHERITED_VALUE_BINDING_P
+	     here.  This function is only used to register bindings
+	     from with the class definition itself.  */
+	  INHERITED_VALUE_BINDING_P (binding) = 0;
+	  return true;
 	}
     }
-  timevar_cond_stop (TV_NAME_LOOKUP, subtime);
-  return t;
-}
 
-/* Insert USED into the using list of USER. Set INDIRECT_flag if this
-   directive is not directly from the source. Also find the common
-   ancestor and let our users know about the new namespace */
+  /* Note that we declared this value so that we can issue an error if
+     this is an invalid redeclaration of a name already used for some
+     other purpose.  */
+  note_name_declared_in_class (name, decl);
 
-static void
-add_using_namespace_1 (tree user, tree used, bool indirect)
-{
-  tree t;
-  /* Using oneself is a no-op.  */
-  if (user == used)
-    return;
-  gcc_assert (TREE_CODE (user) == NAMESPACE_DECL);
-  gcc_assert (TREE_CODE (used) == NAMESPACE_DECL);
-  /* Check if we already have this.  */
-  t = purpose_member (used, DECL_NAMESPACE_USING (user));
-  if (t != NULL_TREE)
+  /* If we didn't replace an existing binding, put the binding on the
+     stack of bindings for the identifier, and update the shadowed
+     list.  */
+  if (binding && binding->scope == class_binding_level)
+    /* Supplement the existing binding.  */
+    ok = supplement_binding (binding, decl);
+  else
     {
-      if (!indirect)
-	/* Promote to direct usage.  */
-	TREE_INDIRECT_USING (t) = 0;
-      return;
+      /* Create a new binding.  */
+      push_binding (name, decl, class_binding_level);
+      ok = true;
     }
 
-  /* Add used to the user's using list.  */
-  DECL_NAMESPACE_USING (user)
-    = tree_cons (used, namespace_ancestor (user, used),
-		 DECL_NAMESPACE_USING (user));
-
-  TREE_INDIRECT_USING (DECL_NAMESPACE_USING (user)) = indirect;
-
-  /* Add user to the used's users list.  */
-  DECL_NAMESPACE_USERS (used)
-    = tree_cons (user, 0, DECL_NAMESPACE_USERS (used));
-
-  /* Recursively add all namespaces used.  */
-  for (t = DECL_NAMESPACE_USING (used); t; t = TREE_CHAIN (t))
-    /* indirect usage */
-    add_using_namespace_1 (user, TREE_PURPOSE (t), 1);
-
-  /* Tell everyone using us about the new used namespaces.  */
-  for (t = DECL_NAMESPACE_USERS (user); t; t = TREE_CHAIN (t))
-    add_using_namespace_1 (TREE_PURPOSE (t), used, 1);
+  return ok;
 }
 
-/* Wrapper for add_using_namespace_1.  */
+/* Wrapper for push_class_level_binding_1.  */
 
-static void
-add_using_namespace (tree user, tree used, bool indirect)
+bool
+push_class_level_binding (tree name, tree x)
 {
+  bool ret;
   bool subtime = timevar_cond_start (TV_NAME_LOOKUP);
-  add_using_namespace_1 (user, used, indirect);
+  ret = push_class_level_binding_1 (name, x);
   timevar_cond_stop (TV_NAME_LOOKUP, subtime);
+  return ret;
 }
 
-/* Process a using-declaration not appearing in class or local scope.  */
-
-void
-do_toplevel_using_decl (tree decl, tree scope, tree name)
-{
-  tree oldval, oldtype, newval, newtype;
-  tree orig_decl = decl;
-  cxx_binding *binding;
-
-  decl = validate_nonmember_using_decl (decl, scope, name);
-  if (decl == NULL_TREE)
-    return;
-
-  binding = binding_for_name (NAMESPACE_LEVEL (current_namespace), name);
-
-  oldval = binding->value;
-  oldtype = binding->type;
-
-  do_nonmember_using_decl (scope, name, oldval, oldtype, &newval, &newtype);
-
-  /* Emit debug info.  */
-  if (!processing_template_decl)
-    cp_emit_debug_info_for_using (orig_decl, current_namespace);
-
-  /* Copy declarations found.  */
-  if (newval)
-    binding->value = newval;
-  if (newtype)
-    binding->type = newtype;
-}
-
-/* Process a using-directive.  */
+/* Process "using SCOPE::NAME" in a class scope.  Return the
+   USING_DECL created.  */
 
-void
-do_using_directive (tree name_space)
+tree
+do_class_using_decl (tree scope, tree name)
 {
-  tree context = NULL_TREE;
-
-  if (name_space == error_mark_node)
-    return;
+  /* The USING_DECL returned by this function.  */
+  tree value;
+  /* The declaration (or declarations) name by this using
+     declaration.  NULL if we are in a template and cannot figure out
+     what has been named.  */
+  tree decl;
+  /* True if SCOPE is a dependent type.  */
+  bool scope_dependent_p;
+  /* True if SCOPE::NAME is dependent.  */
+  bool name_dependent_p;
+  /* True if any of the bases of CURRENT_CLASS_TYPE are dependent.  */
+  bool bases_dependent_p;
+  tree binfo;
 
-  gcc_assert (TREE_CODE (name_space) == NAMESPACE_DECL);
+  if (name == error_mark_node)
+    return NULL_TREE;
 
-  if (building_stmt_list_p ())
-    add_stmt (build_stmt (input_location, USING_STMT, name_space));
-  name_space = ORIGINAL_NAMESPACE (name_space);
+  if (!scope || !TYPE_P (scope))
+    {
+      error ("using-declaration for non-member at class scope");
+      return NULL_TREE;
+    }
 
-  if (!toplevel_bindings_p ())
+  /* Make sure the name is not invalid */
+  if (TREE_CODE (name) == BIT_NOT_EXPR)
     {
-      push_using_directive (name_space);
+      error ("%<%T::%D%> names destructor", scope, name);
+      return NULL_TREE;
     }
-  else
+  /* Using T::T declares inheriting ctors, even if T is a typedef.  */
+  if (MAYBE_CLASS_TYPE_P (scope)
+      && (name == TYPE_IDENTIFIER (scope)
+	  || constructor_name_p (name, scope)))
     {
-      /* direct usage */
-      add_using_namespace (current_namespace, name_space, 0);
-      if (current_namespace != global_namespace)
-	context = current_namespace;
-
-      /* Emit debugging info.  */
-      if (!processing_template_decl)
-	(*debug_hooks->imported_module_or_decl) (name_space, NULL_TREE,
-						 context, false);
+      maybe_warn_cpp0x (CPP0X_INHERITING_CTORS);
+      name = ctor_identifier;
+      CLASSTYPE_NON_AGGREGATE (current_class_type) = true;
     }
-}
+  if (constructor_name_p (name, current_class_type))
+    {
+      error ("%<%T::%D%> names constructor in %qT",
+	     scope, name, current_class_type);
+      return NULL_TREE;
+    }
+
+  scope_dependent_p = dependent_scope_p (scope);
+  name_dependent_p = (scope_dependent_p
+		      || (IDENTIFIER_TYPENAME_P (name)
+			  && dependent_type_p (TREE_TYPE (name))));
 
-/* Deal with a using-directive seen by the parser.  Currently we only
-   handle attributes here, since they cannot appear inside a template.  */
+  bases_dependent_p = any_dependent_bases_p ();
 
-void
-parse_using_directive (tree name_space, tree attribs)
-{
-  do_using_directive (name_space);
+  decl = NULL_TREE;
 
-  if (attribs == error_mark_node)
-    return;
+  /* From [namespace.udecl]:
 
-  for (tree a = attribs; a; a = TREE_CHAIN (a))
+       A using-declaration used as a member-declaration shall refer to a
+       member of a base class of the class being defined.
+
+     In general, we cannot check this constraint in a template because
+     we do not know the entire set of base classes of the current
+     class type. Morover, if SCOPE is dependent, it might match a
+     non-dependent base.  */
+
+  if (!scope_dependent_p)
     {
-      tree name = get_attribute_name (a);
-      if (is_attribute_p ("strong", name))
+      base_kind b_kind;
+      binfo = lookup_base (current_class_type, scope, ba_any, &b_kind,
+			   tf_warning_or_error);
+      if (b_kind < bk_proper_base)
 	{
-	  warning (OPT_Wdeprecated, "strong using is deprecated; use inline "
-		   "namespaces instead");
-	  if (!toplevel_bindings_p ())
-	    error ("strong using only meaningful at namespace scope");
-	  else if (name_space != error_mark_node)
+	  if (!bases_dependent_p || b_kind == bk_same_type)
 	    {
-	      if (!is_ancestor (current_namespace, name_space))
-		error ("current namespace %qD does not enclose strongly used namespace %qD",
-		       current_namespace, name_space);
-	      DECL_NAMESPACE_ASSOCIATIONS (name_space)
-		= tree_cons (current_namespace, 0,
-			     DECL_NAMESPACE_ASSOCIATIONS (name_space));
+	      error_not_base_type (scope, current_class_type);
+	      return NULL_TREE;
 	    }
 	}
-      else
-	warning (OPT_Wattributes, "%qD attribute directive ignored", name);
+      else if (name == ctor_identifier
+	       && BINFO_INHERITANCE_CHAIN (BINFO_INHERITANCE_CHAIN (binfo)))
+	{
+	  error ("cannot inherit constructors from indirect base %qT", scope);
+	  return NULL_TREE;
+	}
+      else if (!name_dependent_p)
+	{
+	  decl = lookup_member (binfo, name, 0, false, tf_warning_or_error);
+	  if (!decl)
+	    {
+	      error ("no members matching %<%T::%D%> in %q#T", scope, name,
+		     scope);
+	      return NULL_TREE;
+	    }
+	  /* The binfo from which the functions came does not matter.  */
+	  if (BASELINK_P (decl))
+	    decl = BASELINK_FUNCTIONS (decl);
+	}
     }
-}
 
-/* Like pushdecl, only it places X in the global scope if appropriate.
-   Calls cp_finish_decl to register the variable, initializing it with
-   *INIT, if INIT is non-NULL.  */
+  value = build_lang_decl (USING_DECL, name, NULL_TREE);
+  USING_DECL_DECLS (value) = decl;
+  USING_DECL_SCOPE (value) = scope;
+  DECL_DEPENDENT_P (value) = !decl;
 
-static tree
-pushdecl_top_level_1 (tree x, tree *init, bool is_friend)
-{
-  bool subtime = timevar_cond_start (TV_NAME_LOOKUP);
-  push_to_top_level ();
-  x = pushdecl_namespace_level (x, is_friend);
-  if (init)
-    cp_finish_decl (x, *init, false, NULL_TREE, 0);
-  pop_from_top_level ();
-  timevar_cond_stop (TV_NAME_LOOKUP, subtime);
-  return x;
+  return value;
 }
 
-/* Like pushdecl, only it places X in the global scope if appropriate.  */
+
+/* Return the binding value for name in scope.  */
 
-tree
-pushdecl_top_level (tree x)
+
+static tree
+namespace_binding_1 (tree name, tree scope)
 {
-  return pushdecl_top_level_1 (x, NULL, false);
-}
+  cxx_binding *binding;
 
-/* Like pushdecl_top_level, but adding the IS_FRIEND parameter.  */
+  if (SCOPE_FILE_SCOPE_P (scope))
+    scope = global_namespace;
+  else
+    /* Unnecessary for the global namespace because it can't be an alias. */
+    scope = ORIGINAL_NAMESPACE (scope);
 
-tree
-pushdecl_top_level_maybe_friend (tree x, bool is_friend)
-{
-  return pushdecl_top_level_1 (x, NULL, is_friend);
-}
+  binding = cp_binding_level_find_binding_for_name (NAMESPACE_LEVEL (scope), name);
 
-/* Like pushdecl, only it places X in the global scope if
-   appropriate.  Calls cp_finish_decl to register the variable,
-   initializing it with INIT.  */
+  return binding ? binding->value : NULL_TREE;
+}
 
 tree
-pushdecl_top_level_and_finish (tree x, tree init)
+namespace_binding (tree name, tree scope)
 {
-  return pushdecl_top_level_1 (x, &init, false);
+  tree ret;
+  bool subtime = timevar_cond_start (TV_NAME_LOOKUP);
+  ret = namespace_binding_1 (name, scope);
+  timevar_cond_stop (TV_NAME_LOOKUP, subtime);
+  return ret;
 }
 
-/* Combines two sets of overloaded functions into an OVERLOAD chain, removing
-   duplicates.  The first list becomes the tail of the result.
-
-   The algorithm is O(n^2).  We could get this down to O(n log n) by
-   doing a sort on the addresses of the functions, if that becomes
-   necessary.  */
+/* Set the binding value for name in scope.  */
 
-static tree
-merge_functions (tree s1, tree s2)
+static void
+set_namespace_binding_1 (tree name, tree scope, tree val)
 {
-  for (; s2; s2 = OVL_NEXT (s2))
-    {
-      tree fn2 = OVL_CURRENT (s2);
-      tree fns1;
-
-      for (fns1 = s1; fns1; fns1 = OVL_NEXT (fns1))
-	{
-	  tree fn1 = OVL_CURRENT (fns1);
-
-	  /* If the function from S2 is already in S1, there is no
-	     need to add it again.  For `extern "C"' functions, we
-	     might have two FUNCTION_DECLs for the same function, in
-	     different namespaces, but let's leave them in case
-	     they have different default arguments.  */
-	  if (fn1 == fn2)
-	    break;
-	}
+  cxx_binding *b;
 
-      /* If we exhausted all of the functions in S1, FN2 is new.  */
-      if (!fns1)
-	s1 = build_overload (fn2, s1);
-    }
-  return s1;
+  if (scope == NULL_TREE)
+    scope = global_namespace;
+  b = binding_for_name (NAMESPACE_LEVEL (scope), name);
+  if (!b->value
+      /* For templates and using we create a single element OVERLOAD.
+	 Look for the chain to know whether this is really augmenting
+	 an existing overload.  */
+      || (TREE_CODE (val) == OVERLOAD && OVL_CHAIN (val))
+      || val == error_mark_node)
+    b->value = val;
+  else
+    supplement_binding (b, val);
 }
 
-/* Returns TRUE iff OLD and NEW are the same entity.
-
-   3 [basic]/3: An entity is a value, object, reference, function,
-   enumerator, type, class member, template, template specialization,
-   namespace, parameter pack, or this.
-
-   7.3.4 [namespace.udir]/4: If name lookup finds a declaration for a name
-   in two different namespaces, and the declarations do not declare the
-   same entity and do not declare functions, the use of the name is
-   ill-formed.  */
+/* Wrapper for set_namespace_binding_1.  */
 
-static bool
-same_entity_p (tree one, tree two)
+void
+set_namespace_binding (tree name, tree scope, tree val)
 {
-  if (one == two)
-    return true;
-  if (!one || !two)
-    return false;
-  if (TREE_CODE (one) == TYPE_DECL
-      && TREE_CODE (two) == TYPE_DECL
-      && same_type_p (TREE_TYPE (one), TREE_TYPE (two)))
-    return true;
-  return false;
+  bool subtime = timevar_cond_start (TV_NAME_LOOKUP);
+  set_namespace_binding_1 (name, scope, val);
+  timevar_cond_stop (TV_NAME_LOOKUP, subtime);
 }
 
-/* This should return an error not all definitions define functions.
-   It is not an error if we find two functions with exactly the
-   same signature, only if these are selected in overload resolution.
-   old is the current set of bindings, new_binding the freshly-found binding.
-   XXX Do we want to give *all* candidates in case of ambiguity?
-   XXX In what way should I treat extern declarations?
-   XXX I don't want to repeat the entire duplicate_decls here */
+/* Set the context of a declaration to scope. Complain if we are not
+   outside scope.  */
 
-static void
-ambiguous_decl (struct scope_binding *old, cxx_binding *new_binding, int flags)
+void
+set_decl_namespace (tree decl, tree scope, bool friendp)
 {
-  tree val, type;
-  gcc_assert (old != NULL);
+  tree old;
 
-  /* Copy the type.  */
-  type = new_binding->type;
-  if (LOOKUP_NAMESPACES_ONLY (flags)
-      || (type && hidden_name_p (type) && !(flags & LOOKUP_HIDDEN)))
-    type = NULL_TREE;
+  /* Get rid of namespace aliases.  */
+  scope = ORIGINAL_NAMESPACE (scope);
 
-  /* Copy the value.  */
-  val = new_binding->value;
-  if (val)
-    {
-      if (!(flags & LOOKUP_HIDDEN))
-	val = remove_hidden_names (val);
-      if (val)
-	switch (TREE_CODE (val))
-	  {
-	  case TEMPLATE_DECL:
-	    /* If we expect types or namespaces, and not templates,
-	       or this is not a template class.  */
-	    if ((LOOKUP_QUALIFIERS_ONLY (flags)
-		 && !DECL_TYPE_TEMPLATE_P (val)))
-	      val = NULL_TREE;
-	    break;
-	  case TYPE_DECL:
-	    if (LOOKUP_NAMESPACES_ONLY (flags)
-		|| (type && (flags & LOOKUP_PREFER_TYPES)))
-	      val = NULL_TREE;
-	    break;
-	  case NAMESPACE_DECL:
-	    if (LOOKUP_TYPES_ONLY (flags))
-	      val = NULL_TREE;
-	    break;
-	  case FUNCTION_DECL:
-	    /* Ignore built-in functions that are still anticipated.  */
-	    if (LOOKUP_QUALIFIERS_ONLY (flags))
-	      val = NULL_TREE;
-	    break;
-	  default:
-	    if (LOOKUP_QUALIFIERS_ONLY (flags))
-	      val = NULL_TREE;
-	  }
-    }
+  /* It is ok for friends to be qualified in parallel space.  */
+  if (!friendp && !is_ancestor (current_namespace, scope))
+    error ("declaration of %qD not in a namespace surrounding %qD",
+	   decl, scope);
+  DECL_CONTEXT (decl) = FROB_CONTEXT (scope);
 
-  /* If val is hidden, shift down any class or enumeration name.  */
-  if (!val)
+  /* Writing "int N::i" to declare a variable within "N" is invalid.  */
+  if (scope == current_namespace)
     {
-      val = type;
-      type = NULL_TREE;
+      if (at_namespace_scope_p ())
+	error ("explicit qualification in declaration of %qD",
+	       decl);
+      return;
     }
 
-  if (!old->value)
-    old->value = val;
-  else if (val && !same_entity_p (val, old->value))
+  /* See whether this has been declared in the namespace.  */
+  old = lookup_qualified_name (scope, DECL_NAME (decl), /*type*/false,
+			       /*complain*/true, /*hidden*/true);
+  if (old == error_mark_node)
+    /* No old declaration at all.  */
+    goto complain;
+  /* If it's a TREE_LIST, the result of the lookup was ambiguous.  */
+  if (TREE_CODE (old) == TREE_LIST)
     {
-      if (is_overloaded_fn (old->value) && is_overloaded_fn (val))
-	old->value = merge_functions (old->value, val);
-      else
+      error ("reference to %qD is ambiguous", decl);
+      print_candidates (old);
+      return;
+    }
+  if (!is_overloaded_fn (decl))
+    {
+      /* We might have found OLD in an inline namespace inside SCOPE.  */
+      if (TREE_CODE (decl) == TREE_CODE (old))
+	DECL_CONTEXT (decl) = DECL_CONTEXT (old);
+      /* Don't compare non-function decls with decls_match here, since
+	 it can't check for the correct constness at this
+	 point. pushdecl will find those errors later.  */
+      return;
+    }
+  /* Since decl is a function, old should contain a function decl.  */
+  if (!is_overloaded_fn (old))
+    goto complain;
+  /* We handle these in check_explicit_instantiation_namespace.  */
+  if (processing_explicit_instantiation)
+    return;
+  if (processing_template_decl || processing_specialization)
+    /* We have not yet called push_template_decl to turn a
+       FUNCTION_DECL into a TEMPLATE_DECL, so the declarations won't
+       match.  But, we'll check later, when we construct the
+       template.  */
+    return;
+  /* Instantiations or specializations of templates may be declared as
+     friends in any namespace.  */
+  if (friendp && DECL_USE_TEMPLATE (decl))
+    return;
+  if (is_overloaded_fn (old))
+    {
+      tree found = NULL_TREE;
+      tree elt = old;
+      for (; elt; elt = OVL_NEXT (elt))
 	{
-	  old->value = tree_cons (NULL_TREE, old->value,
-				  build_tree_list (NULL_TREE, val));
-	  TREE_TYPE (old->value) = error_mark_node;
+	  tree ofn = OVL_CURRENT (elt);
+	  /* Adjust DECL_CONTEXT first so decls_match will return true
+	     if DECL will match a declaration in an inline namespace.  */
+	  DECL_CONTEXT (decl) = DECL_CONTEXT (ofn);
+	  if (decls_match (decl, ofn))
+	    {
+	      if (found && !decls_match (found, ofn))
+		{
+		  DECL_CONTEXT (decl) = FROB_CONTEXT (scope);
+		  error ("reference to %qD is ambiguous", decl);
+		  print_candidates (old);
+		  return;
+		}
+	      found = ofn;
+	    }
+	}
+      if (found)
+	{
+	  if (!is_associated_namespace (scope, CP_DECL_CONTEXT (found)))
+	    goto complain;
+	  if (DECL_HIDDEN_FRIEND_P (found))
+	    {
+	      pedwarn (DECL_SOURCE_LOCATION (decl), 0,
+		       "%qD has not been declared within %D", decl, scope);
+	      inform (DECL_SOURCE_LOCATION (found), "only here as a friend");
+	    }
+	  DECL_CONTEXT (decl) = DECL_CONTEXT (found);
+	  return;
 	}
     }
-
-  if (!old->type)
-    old->type = type;
-  else if (type && old->type != type)
+  else
     {
-      old->type = tree_cons (NULL_TREE, old->type,
-			     build_tree_list (NULL_TREE, type));
-      TREE_TYPE (old->type) = error_mark_node;
+      DECL_CONTEXT (decl) = DECL_CONTEXT (old);
+      if (decls_match (decl, old))
+	return;
     }
+
+  /* It didn't work, go back to the explicit scope.  */
+  DECL_CONTEXT (decl) = FROB_CONTEXT (scope);
+ complain:
+  error ("%qD should have been declared inside %qD", decl, scope);
 }
 
-/* Return the declarations that are members of the namespace NS.  */
+/* Return the namespace where the current declaration is declared.  */
 
 tree
-cp_namespace_decls (tree ns)
+current_decl_namespace (void)
 {
-  return NAMESPACE_LEVEL (ns)->names;
-}
-
-/* Combine prefer_type and namespaces_only into flags.  */
+  tree result;
+  /* If we have been pushed into a different namespace, use it.  */
+  if (!vec_safe_is_empty (decl_namespace_list))
+    return decl_namespace_list->last ();
 
-static int
-lookup_flags (int prefer_type, int namespaces_only)
-{
-  if (namespaces_only)
-    return LOOKUP_PREFER_NAMESPACES;
-  if (prefer_type > 1)
-    return LOOKUP_PREFER_TYPES;
-  if (prefer_type > 0)
-    return LOOKUP_PREFER_BOTH;
-  return 0;
+  if (current_class_type)
+    result = decl_namespace_context (current_class_type);
+  else if (current_function_decl)
+    result = decl_namespace_context (current_function_decl);
+  else
+    result = current_namespace;
+  return result;
 }
 
-/* Given a lookup that returned VAL, use FLAGS to decide if we want to
-   ignore it or not.  Subroutine of lookup_name_real and
-   lookup_type_scope.  */
+/* Process any ATTRIBUTES on a namespace definition.  Returns true if
+   attribute visibility is seen.  */
 
-static bool
-qualify_lookup (tree val, int flags)
+bool
+handle_namespace_attrs (tree ns, tree attributes)
 {
-  if (val == NULL_TREE)
-    return false;
-  if ((flags & LOOKUP_PREFER_NAMESPACES) && TREE_CODE (val) == NAMESPACE_DECL)
-    return true;
-  if (flags & LOOKUP_PREFER_TYPES)
+  tree d;
+  bool saw_vis = false;
+
+  for (d = attributes; d; d = TREE_CHAIN (d))
     {
-      tree target_val = strip_using_decl (val);
-      if (TREE_CODE (target_val) == TYPE_DECL
-	  || TREE_CODE (target_val) == TEMPLATE_DECL)
-	return true;
+      tree name = get_attribute_name (d);
+      tree args = TREE_VALUE (d);
+
+      if (is_attribute_p ("visibility", name))
+	{
+	  /* attribute visibility is a property of the syntactic block
+	     rather than the namespace as a whole, so we don't touch the
+	     NAMESPACE_DECL at all.  */
+	  tree x = args ? TREE_VALUE (args) : NULL_TREE;
+	  if (x == NULL_TREE || TREE_CODE (x) != STRING_CST || TREE_CHAIN (args))
+	    {
+	      warning (OPT_Wattributes,
+		       "%qD attribute requires a single NTBS argument",
+		       name);
+	      continue;
+	    }
+
+	  if (!TREE_PUBLIC (ns))
+	    warning (OPT_Wattributes,
+		     "%qD attribute is meaningless since members of the "
+		     "anonymous namespace get local symbols", name);
+
+	  push_visibility (TREE_STRING_POINTER (x), 1);
+	  saw_vis = true;
+	}
+      else if (is_attribute_p ("abi_tag", name))
+	{
+	  if (!DECL_NAMESPACE_ASSOCIATIONS (ns))
+	    {
+	      warning (OPT_Wattributes, "ignoring %qD attribute on non-inline "
+		       "namespace", name);
+	      continue;
+	    }
+	  if (!DECL_NAME (ns))
+	    {
+	      warning (OPT_Wattributes, "ignoring %qD attribute on anonymous "
+		       "namespace", name);
+	      continue;
+	    }
+	  if (!args)
+	    {
+	      tree dn = DECL_NAME (ns);
+	      args = build_string (IDENTIFIER_LENGTH (dn) + 1,
+				   IDENTIFIER_POINTER (dn));
+	      TREE_TYPE (args) = char_array_type_node;
+	      args = fix_string_type (args);
+	      args = build_tree_list (NULL_TREE, args);
+	    }
+	  if (check_abi_tag_args (args, name))
+	    DECL_ATTRIBUTES (ns) = tree_cons (name, args,
+					      DECL_ATTRIBUTES (ns));
+	}
+      else
+	{
+	  warning (OPT_Wattributes, "%qD attribute directive ignored",
+		   name);
+	  continue;
+	}
     }
-  if (flags & (LOOKUP_PREFER_NAMESPACES | LOOKUP_PREFER_TYPES))
-    return false;
-  /* Look through lambda things that we shouldn't be able to see.  */
-  if (is_lambda_ignored_entity (val))
-    return false;
-  return true;
-}
 
-/* Given a lookup that returned VAL, decide if we want to ignore it or
-   not based on DECL_ANTICIPATED.  */
+  return saw_vis;
+}
+/* Temporarily set the namespace for the current declaration.  */
 
-bool
-hidden_name_p (tree val)
+void
+push_decl_namespace (tree decl)
 {
-  if (DECL_P (val)
-      && DECL_LANG_SPECIFIC (val)
-      && TYPE_FUNCTION_OR_TEMPLATE_DECL_P (val)
-      && DECL_ANTICIPATED (val))
-    return true;
-  if (TREE_CODE (val) == OVERLOAD)
-    {
-      for (tree o = val; o; o = OVL_CHAIN (o))
-	if (!hidden_name_p (OVL_FUNCTION (o)))
-	  return false;
-      return true;
-    }
-  return false;
+  if (TREE_CODE (decl) != NAMESPACE_DECL)
+    decl = decl_namespace_context (decl);
+  vec_safe_push (decl_namespace_list, ORIGINAL_NAMESPACE (decl));
 }
 
-/* Remove any hidden declarations from a possibly overloaded set
-   of functions.  */
+/* [namespace.memdef]/2 */
 
-tree
-remove_hidden_names (tree fns)
+void
+pop_decl_namespace (void)
 {
-  if (!fns)
-    return fns;
+  decl_namespace_list->pop ();
+}
 
-  if (DECL_P (fns) && hidden_name_p (fns))
-    fns = NULL_TREE;
-  else if (TREE_CODE (fns) == OVERLOAD)
-    {
-      tree o;
+/* Return the namespace that is the common ancestor
+   of two given namespaces.  */
 
-      for (o = fns; o; o = OVL_NEXT (o))
-	if (hidden_name_p (OVL_CURRENT (o)))
-	  break;
-      if (o)
-	{
-	  tree n = NULL_TREE;
+static tree
+namespace_ancestor_1 (tree ns1, tree ns2)
+{
+  tree nsr;
+  if (is_ancestor (ns1, ns2))
+    nsr = ns1;
+  else
+    nsr = namespace_ancestor_1 (CP_DECL_CONTEXT (ns1), ns2);
+  return nsr;
+}
 
-	  for (o = fns; o; o = OVL_NEXT (o))
-	    if (!hidden_name_p (OVL_CURRENT (o)))
-	      n = build_overload (OVL_CURRENT (o), n);
-	  fns = n;
-	}
-    }
+/* Wrapper for namespace_ancestor_1.  */
 
-  return fns;
+static tree
+namespace_ancestor (tree ns1, tree ns2)
+{
+  tree nsr;
+  bool subtime = timevar_cond_start (TV_NAME_LOOKUP);
+  nsr = namespace_ancestor_1 (ns1, ns2);
+  timevar_cond_stop (TV_NAME_LOOKUP, subtime);
+  return nsr;
 }
 
-/* Suggest alternatives for NAME, an IDENTIFIER_NODE for which name
-   lookup failed.  Search through all available namespaces and print out
-   possible candidates.  If no exact matches are found, and
-   SUGGEST_MISSPELLINGS is true, then also look for near-matches and
-   suggest the best near-match, if there is one.  */
+/* Process a namespace-alias declaration.  */
 
 void
-suggest_alternatives_for (location_t location, tree name,
-			  bool suggest_misspellings)
+do_namespace_alias (tree alias, tree name_space)
 {
-  vec<tree> candidates = vNULL;
-  vec<tree> namespaces_to_search = vNULL;
-  int max_to_search = PARAM_VALUE (CXX_MAX_NAMESPACES_FOR_DIAGNOSTIC_HELP);
-  int n_searched = 0;
-  tree t;
-  unsigned ix;
-
-  namespaces_to_search.safe_push (global_namespace);
+  if (name_space == error_mark_node)
+    return;
 
-  while (!namespaces_to_search.is_empty ()
-	 && n_searched < max_to_search)
-    {
-      tree scope = namespaces_to_search.pop ();
-      struct scope_binding binding = EMPTY_SCOPE_BINDING;
-      cp_binding_level *level = NAMESPACE_LEVEL (scope);
+  gcc_assert (TREE_CODE (name_space) == NAMESPACE_DECL);
 
-      /* Look in this namespace.  */
-      qualified_lookup_using_namespace (name, scope, &binding, 0);
+  name_space = ORIGINAL_NAMESPACE (name_space);
 
-      n_searched++;
+  /* Build the alias.  */
+  alias = build_lang_decl (NAMESPACE_DECL, alias, void_type_node);
+  DECL_NAMESPACE_ALIAS (alias) = name_space;
+  DECL_EXTERNAL (alias) = 1;
+  DECL_CONTEXT (alias) = FROB_CONTEXT (current_scope ());
+  pushdecl (alias);
 
-      if (binding.value)
-	candidates.safe_push (binding.value);
+  /* Emit debug info for namespace alias.  */
+  if (!building_stmt_list_p ())
+    (*debug_hooks->early_global_decl) (alias);
+}
 
-      /* Add child namespaces.  */
-      for (t = level->namespaces; t; t = DECL_CHAIN (t))
-	namespaces_to_search.safe_push (t);
-    }
+/* Like pushdecl, only it places X in the current namespace,
+   if appropriate.  */
 
-  /* If we stopped before we could examine all namespaces, inform the
-     user.  Do this even if we don't have any candidates, since there
-     might be more candidates further down that we weren't able to
-     find.  */
-  if (n_searched >= max_to_search
-      && !namespaces_to_search.is_empty ())
-    inform (location,
-	    "maximum limit of %d namespaces searched for %qE",
-	    max_to_search, name);
+tree
+pushdecl_namespace_level (tree x, bool is_friend)
+{
+  cp_binding_level *b = current_binding_level;
+  tree t;
 
-  namespaces_to_search.release ();
+  bool subtime = timevar_cond_start (TV_NAME_LOOKUP);
+  t = pushdecl_with_scope (x, NAMESPACE_LEVEL (current_namespace), is_friend);
 
-  /* Nothing useful to report for NAME.  Report on likely misspellings,
-     or do nothing.  */
-  if (candidates.is_empty ())
+  /* Now, the type_shadowed stack may screw us.  Munge it so it does
+     what we want.  */
+  if (TREE_CODE (t) == TYPE_DECL)
     {
-      if (suggest_misspellings)
+      tree name = DECL_NAME (t);
+      tree newval;
+      tree *ptr = (tree *)0;
+      for (; !global_scope_p (b); b = b->level_chain)
 	{
-	  const char *fuzzy_name = lookup_name_fuzzy (name, FUZZY_LOOKUP_NAME);
-	  if (fuzzy_name)
-	    {
-	      gcc_rich_location richloc (location);
-	      richloc.add_fixit_replace (fuzzy_name);
-	      inform_at_rich_loc (&richloc, "suggested alternative: %qs",
-				  fuzzy_name);
-	    }
+	  tree shadowed = b->type_shadowed;
+	  for (; shadowed; shadowed = TREE_CHAIN (shadowed))
+	    if (TREE_PURPOSE (shadowed) == name)
+	      {
+		ptr = &TREE_VALUE (shadowed);
+		/* Can't break out of the loop here because sometimes
+		   a binding level will have duplicate bindings for
+		   PT names.  It's gross, but I haven't time to fix it.  */
+	      }
+	}
+      newval = TREE_TYPE (t);
+      if (ptr == (tree *)0)
+	{
+	  /* @@ This shouldn't be needed.  My test case "zstring.cc" trips
+	     up here if this is changed to an assertion.  --KR  */
+	  SET_IDENTIFIER_TYPE_VALUE (name, t);
+	}
+      else
+	{
+	  *ptr = newval;
 	}
-      return;
     }
-
-  inform_n (location, candidates.length (),
-	    "suggested alternative:",
-	    "suggested alternatives:");
-
-  FOR_EACH_VEC_ELT (candidates, ix, t)
-    inform (location_of (t), "  %qE", t);
-
-  candidates.release ();
+  timevar_cond_stop (TV_NAME_LOOKUP, subtime);
+  return t;
 }
 
-/* Subroutine of maybe_suggest_missing_header for handling unrecognized names
-   for some of the most common names within "std::".
-   Given non-NULL NAME, a name for lookup within "std::", return the header
-   name defining it within the C++ Standard Library (without '<' and '>'),
-   or NULL.  */
+/* Insert USED into the using list of USER. Set INDIRECT_flag if this
+   directive is not directly from the source. Also find the common
+   ancestor and let our users know about the new namespace */
 
-static const char *
-get_std_name_hint (const char *name)
+static void
+add_using_namespace_1 (tree user, tree used, bool indirect)
 {
-  struct std_name_hint
-  {
-    const char *name;
-    const char *header;
-  };
-  static const std_name_hint hints[] = {
-    /* <array>.  */
-    {"array", "array"}, // C++11
-    /* <deque>.  */
-    {"deque", "deque"},
-    /* <forward_list>.  */
-    {"forward_list", "forward_list"},  // C++11
-    /* <fstream>.  */
-    {"basic_filebuf", "fstream"},
-    {"basic_ifstream", "fstream"},
-    {"basic_ofstream", "fstream"},
-    {"basic_fstream", "fstream"},
-    /* <iostream>.  */
-    {"cin", "iostream"},
-    {"cout", "iostream"},
-    {"cerr", "iostream"},
-    {"clog", "iostream"},
-    {"wcin", "iostream"},
-    {"wcout", "iostream"},
-    {"wclog", "iostream"},
-    /* <list>.  */
-    {"list", "list"},
-    /* <map>.  */
-    {"map", "map"},
-    {"multimap", "map"},
-    /* <queue>.  */
-    {"queue", "queue"},
-    {"priority_queue", "queue"},
-    /* <ostream>.  */
-    {"ostream", "ostream"},
-    {"wostream", "ostream"},
-    {"ends", "ostream"},
-    {"flush", "ostream"},
-    {"endl", "ostream"},
-    /* <set>.  */
-    {"set", "set"},
-    {"multiset", "set"},
-    /* <sstream>.  */
-    {"basic_stringbuf", "sstream"},
-    {"basic_istringstream", "sstream"},
-    {"basic_ostringstream", "sstream"},
-    {"basic_stringstream", "sstream"},
-    /* <stack>.  */
-    {"stack", "stack"},
-    /* <string>.  */
-    {"string", "string"},
-    {"wstring", "string"},
-    {"u16string", "string"},
-    {"u32string", "string"},
-    /* <unordered_map>.  */
-    {"unordered_map", "unordered_map"}, // C++11
-    {"unordered_multimap", "unordered_map"}, // C++11
-    /* <unordered_set>.  */
-    {"unordered_set", "unordered_set"}, // C++11
-    {"unordered_multiset", "unordered_set"}, // C++11
-    /* <vector>.  */
-    {"vector", "vector"},
-  };
-  const size_t num_hints = sizeof (hints) / sizeof (hints[0]);
-  for (size_t i = 0; i < num_hints; i++)
+  tree t;
+  /* Using oneself is a no-op.  */
+  if (user == used)
+    return;
+  gcc_assert (TREE_CODE (user) == NAMESPACE_DECL);
+  gcc_assert (TREE_CODE (used) == NAMESPACE_DECL);
+  /* Check if we already have this.  */
+  t = purpose_member (used, DECL_NAMESPACE_USING (user));
+  if (t != NULL_TREE)
     {
-      if (0 == strcmp (name, hints[i].name))
-	return hints[i].header;
+      if (!indirect)
+	/* Promote to direct usage.  */
+	TREE_INDIRECT_USING (t) = 0;
+      return;
     }
-  return NULL;
+
+  /* Add used to the user's using list.  */
+  DECL_NAMESPACE_USING (user)
+    = tree_cons (used, namespace_ancestor (user, used),
+		 DECL_NAMESPACE_USING (user));
+
+  TREE_INDIRECT_USING (DECL_NAMESPACE_USING (user)) = indirect;
+
+  /* Add user to the used's users list.  */
+  DECL_NAMESPACE_USERS (used)
+    = tree_cons (user, 0, DECL_NAMESPACE_USERS (used));
+
+  /* Recursively add all namespaces used.  */
+  for (t = DECL_NAMESPACE_USING (used); t; t = TREE_CHAIN (t))
+    /* indirect usage */
+    add_using_namespace_1 (user, TREE_PURPOSE (t), 1);
+
+  /* Tell everyone using us about the new used namespaces.  */
+  for (t = DECL_NAMESPACE_USERS (user); t; t = TREE_CHAIN (t))
+    add_using_namespace_1 (TREE_PURPOSE (t), used, 1);
 }
 
-/* Subroutine of suggest_alternative_in_explicit_scope, for use when we have no
-   suggestions to offer.
-   If SCOPE is the "std" namespace, then suggest pertinent header
-   files for NAME.  */
+/* Wrapper for add_using_namespace_1.  */
 
 static void
-maybe_suggest_missing_header (location_t location, tree name, tree scope)
+add_using_namespace (tree user, tree used, bool indirect)
 {
-  if (scope == NULL_TREE)
-    return;
-  if (TREE_CODE (scope) != NAMESPACE_DECL)
-    return;
-  /* We only offer suggestions for the "std" namespace.  */
-  if (scope != std_node)
-    return;
-  gcc_assert (TREE_CODE (name) == IDENTIFIER_NODE);
-
-  const char *name_str = IDENTIFIER_POINTER (name);
-  const char *header_hint = get_std_name_hint (name_str);
-  if (header_hint)
-    inform (location,
-	    "%<std::%s%> is defined in header %<<%s>%>;"
-	    " did you forget to %<#include <%s>%>?",
-	    name_str, header_hint, header_hint);
+  bool subtime = timevar_cond_start (TV_NAME_LOOKUP);
+  add_using_namespace_1 (user, used, indirect);
+  timevar_cond_stop (TV_NAME_LOOKUP, subtime);
 }
 
-/* Look for alternatives for NAME, an IDENTIFIER_NODE for which name
-   lookup failed within the explicitly provided SCOPE.  Suggest the
-   the best meaningful candidates (if any) as a fix-it hint.
-   Return true iff a suggestion was provided.  */
+/* Process a using-declaration not appearing in class or local scope.  */
 
-bool
-suggest_alternative_in_explicit_scope (location_t location, tree name,
-				       tree scope)
+void
+do_toplevel_using_decl (tree decl, tree scope, tree name)
 {
-  /* Resolve any namespace aliases.  */
-  scope = ORIGINAL_NAMESPACE (scope);
+  tree oldval, oldtype, newval, newtype;
+  tree orig_decl = decl;
+  cxx_binding *binding;
 
-  cp_binding_level *level = NAMESPACE_LEVEL (scope);
+  decl = validate_nonmember_using_decl (decl, scope, name);
+  if (decl == NULL_TREE)
+    return;
 
-  best_match <tree, const char *> bm (name);
-  consider_binding_level (name, bm, level, false, FUZZY_LOOKUP_NAME);
+  binding = binding_for_name (NAMESPACE_LEVEL (current_namespace), name);
 
-  /* See if we have a good suggesion for the user.  */
-  const char *fuzzy_name = bm.get_best_meaningful_candidate ();
-  if (fuzzy_name)
-    {
-      gcc_rich_location richloc (location);
-      richloc.add_fixit_replace (fuzzy_name);
-      inform_at_rich_loc (&richloc, "suggested alternative: %qs",
-			  fuzzy_name);
-      return true;
-    }
-  else
-    maybe_suggest_missing_header (location, name, scope);
+  oldval = binding->value;
+  oldtype = binding->type;
 
-  return false;
+  do_nonmember_using_decl (scope, name, oldval, oldtype, &newval, &newtype);
+
+  /* Emit debug info.  */
+  if (!processing_template_decl)
+    cp_emit_debug_info_for_using (orig_decl, current_namespace);
+
+  /* Copy declarations found.  */
+  if (newval)
+    binding->value = newval;
+  if (newtype)
+    binding->type = newtype;
 }
 
-/* Unscoped lookup of a global: iterate over current namespaces,
-   considering using-directives.  */
+/* Process a using-directive.  */
 
-static tree
-unqualified_namespace_lookup_1 (tree name, int flags)
+void
+do_using_directive (tree name_space)
 {
-  tree initial = current_decl_namespace ();
-  tree scope = initial;
-  tree siter;
-  cp_binding_level *level;
-  tree val = NULL_TREE;
+  tree context = NULL_TREE;
 
-  for (; !val; scope = CP_DECL_CONTEXT (scope))
-    {
-      struct scope_binding binding = EMPTY_SCOPE_BINDING;
-      cxx_binding *b =
-	 cp_binding_level_find_binding_for_name (NAMESPACE_LEVEL (scope), name);
+  if (name_space == error_mark_node)
+    return;
 
-      if (b)
-	ambiguous_decl (&binding, b, flags);
+  gcc_assert (TREE_CODE (name_space) == NAMESPACE_DECL);
 
-      /* Add all _DECLs seen through local using-directives.  */
-      for (level = current_binding_level;
-	   level->kind != sk_namespace;
-	   level = level->level_chain)
-	if (!lookup_using_namespace (name, &binding, level->using_directives,
-				     scope, flags))
-	  /* Give up because of error.  */
-	  return error_mark_node;
+  if (building_stmt_list_p ())
+    add_stmt (build_stmt (input_location, USING_STMT, name_space));
+  name_space = ORIGINAL_NAMESPACE (name_space);
 
-      /* Add all _DECLs seen through global using-directives.  */
-      /* XXX local and global using lists should work equally.  */
-      siter = initial;
-      while (1)
-	{
-	  if (!lookup_using_namespace (name, &binding,
-				       DECL_NAMESPACE_USING (siter),
-				       scope, flags))
-	    /* Give up because of error.  */
-	    return error_mark_node;
-	  if (siter == scope) break;
-	  siter = CP_DECL_CONTEXT (siter);
-	}
+  if (!toplevel_bindings_p ())
+    {
+      push_using_directive (name_space);
+    }
+  else
+    {
+      /* direct usage */
+      add_using_namespace (current_namespace, name_space, 0);
+      if (current_namespace != global_namespace)
+	context = current_namespace;
 
-      val = binding.value;
-      if (scope == global_namespace)
-	break;
+      /* Emit debugging info.  */
+      if (!processing_template_decl)
+	(*debug_hooks->imported_module_or_decl) (name_space, NULL_TREE,
+						 context, false);
     }
-  return val;
 }
 
-/* Wrapper for unqualified_namespace_lookup_1.  */
+/* Deal with a using-directive seen by the parser.  Currently we only
+   handle attributes here, since they cannot appear inside a template.  */
 
-static tree
-unqualified_namespace_lookup (tree name, int flags)
+void
+parse_using_directive (tree name_space, tree attribs)
 {
-  tree ret;
-  bool subtime = timevar_cond_start (TV_NAME_LOOKUP);
-  ret = unqualified_namespace_lookup_1 (name, flags);
-  timevar_cond_stop (TV_NAME_LOOKUP, subtime);
-  return ret;
-}
-
-/* Look up NAME (an IDENTIFIER_NODE) in SCOPE (either a NAMESPACE_DECL
-   or a class TYPE).
-
-   If PREFER_TYPE is > 0, we only return TYPE_DECLs or namespaces.
-   If PREFER_TYPE is > 1, we only return TYPE_DECLs.
-
-   Returns a DECL (or OVERLOAD, or BASELINK) representing the
-   declaration found.  If no suitable declaration can be found,
-   ERROR_MARK_NODE is returned.  If COMPLAIN is true and SCOPE is
-   neither a class-type nor a namespace a diagnostic is issued.  */
+  do_using_directive (name_space);
 
-tree
-lookup_qualified_name (tree scope, tree name, int prefer_type, bool complain,
-		       bool find_hidden)
-{
-  tree t = NULL_TREE;
+  if (attribs == error_mark_node)
+    return;
 
-  if (TREE_CODE (scope) == NAMESPACE_DECL)
+  for (tree a = attribs; a; a = TREE_CHAIN (a))
     {
-      struct scope_binding binding = EMPTY_SCOPE_BINDING;
-
-      int flags = lookup_flags (prefer_type, /*namespaces_only*/false);
-      if (find_hidden)
-	flags |= LOOKUP_HIDDEN;
-      if (qualified_lookup_using_namespace (name, scope, &binding, flags))
-	t = binding.value;
+      tree name = get_attribute_name (a);
+      if (is_attribute_p ("strong", name))
+	{
+	  warning (OPT_Wdeprecated, "strong using is deprecated; use inline "
+		   "namespaces instead");
+	  if (!toplevel_bindings_p ())
+	    error ("strong using only meaningful at namespace scope");
+	  else if (name_space != error_mark_node)
+	    {
+	      if (!is_ancestor (current_namespace, name_space))
+		error ("current namespace %qD does not enclose strongly used namespace %qD",
+		       current_namespace, name_space);
+	      DECL_NAMESPACE_ASSOCIATIONS (name_space)
+		= tree_cons (current_namespace, 0,
+			     DECL_NAMESPACE_ASSOCIATIONS (name_space));
+	    }
+	}
+      else
+	warning (OPT_Wattributes, "%qD attribute directive ignored", name);
     }
-  else if (cxx_dialect != cxx98 && TREE_CODE (scope) == ENUMERAL_TYPE)
-    t = lookup_enumerator (scope, name);
-  else if (is_class_type (scope, complain))
-    t = lookup_member (scope, name, 2, prefer_type, tf_warning_or_error);
-
-  if (!t)
-    return error_mark_node;
-  return t;
 }
 
-/* Subroutine of unqualified_namespace_lookup:
-   Add the bindings of NAME in used namespaces to VAL.
-   We are currently looking for names in namespace SCOPE, so we
-   look through USINGS for using-directives of namespaces
-   which have SCOPE as a common ancestor with the current scope.
-   Returns false on errors.  */
+/* Like pushdecl, only it places X in the global scope if appropriate.
+   Calls cp_finish_decl to register the variable, initializing it with
+   *INIT, if INIT is non-NULL.  */
 
-static bool
-lookup_using_namespace (tree name, struct scope_binding *val,
-			tree usings, tree scope, int flags)
+static tree
+pushdecl_top_level_1 (tree x, tree *init, bool is_friend)
 {
-  tree iter;
   bool subtime = timevar_cond_start (TV_NAME_LOOKUP);
-  /* Iterate over all used namespaces in current, searching for using
-     directives of scope.  */
-  for (iter = usings; iter; iter = TREE_CHAIN (iter))
-    if (TREE_VALUE (iter) == scope)
-      {
-	tree used = ORIGINAL_NAMESPACE (TREE_PURPOSE (iter));
-	cxx_binding *val1 =
-	  cp_binding_level_find_binding_for_name (NAMESPACE_LEVEL (used), name);
-	/* Resolve ambiguities.  */
-	if (val1)
-	  ambiguous_decl (val, val1, flags);
-      }
+  push_to_top_level ();
+  x = pushdecl_namespace_level (x, is_friend);
+  if (init)
+    cp_finish_decl (x, *init, false, NULL_TREE, 0);
+  pop_from_top_level ();
   timevar_cond_stop (TV_NAME_LOOKUP, subtime);
-  return val->value != error_mark_node;
+  return x;
+}
+
+/* Like pushdecl, only it places X in the global scope if appropriate.  */
+
+tree
+pushdecl_top_level (tree x)
+{
+  return pushdecl_top_level_1 (x, NULL, false);
 }
 
-/* Returns true iff VEC contains TARGET.  */
+/* Like pushdecl_top_level, but adding the IS_FRIEND parameter.  */
 
-static bool
-tree_vec_contains (vec<tree, va_gc> *vec, tree target)
+tree
+pushdecl_top_level_maybe_friend (tree x, bool is_friend)
 {
-  unsigned int i;
-  tree elt;
-  FOR_EACH_VEC_SAFE_ELT (vec,i,elt)
-    if (elt == target)
-      return true;
-  return false;
+  return pushdecl_top_level_1 (x, NULL, is_friend);
 }
 
-/* [namespace.qual]
-   Accepts the NAME to lookup and its qualifying SCOPE.
-   Returns the name/type pair found into the cxx_binding *RESULT,
-   or false on error.  */
+/* Like pushdecl, only it places X in the global scope if
+   appropriate.  Calls cp_finish_decl to register the variable,
+   initializing it with INIT.  */
 
-static bool
-qualified_lookup_using_namespace (tree name, tree scope,
-				  struct scope_binding *result, int flags)
+tree
+pushdecl_top_level_and_finish (tree x, tree init)
 {
-  /* Maintain a list of namespaces visited...  */
-  vec<tree, va_gc> *seen = NULL;
-  vec<tree, va_gc> *seen_inline = NULL;
-  /* ... and a list of namespace yet to see.  */
-  vec<tree, va_gc> *todo = NULL;
-  vec<tree, va_gc> *todo_maybe = NULL;
-  vec<tree, va_gc> *todo_inline = NULL;
-  tree usings;
-  timevar_start (TV_NAME_LOOKUP);
-  /* Look through namespace aliases.  */
-  scope = ORIGINAL_NAMESPACE (scope);
+  return pushdecl_top_level_1 (x, &init, false);
+}
 
-  query_oracle (name);
+/* Combines two sets of overloaded functions into an OVERLOAD chain, removing
+   duplicates.  The first list becomes the tail of the result.
 
-  /* Algorithm: Starting with SCOPE, walk through the set of used
-     namespaces.  For each used namespace, look through its inline
-     namespace set for any bindings and usings.  If no bindings are
-     found, add any usings seen to the set of used namespaces.  */
-  vec_safe_push (todo, scope);
+   The algorithm is O(n^2).  We could get this down to O(n log n) by
+   doing a sort on the addresses of the functions, if that becomes
+   necessary.  */
 
-  while (todo->length ())
+static tree
+merge_functions (tree s1, tree s2)
+{
+  for (; s2; s2 = OVL_NEXT (s2))
     {
-      bool found_here;
-      scope = todo->pop ();
-      if (tree_vec_contains (seen, scope))
-	continue;
-      vec_safe_push (seen, scope);
-      vec_safe_push (todo_inline, scope);
+      tree fn2 = OVL_CURRENT (s2);
+      tree fns1;
 
-      found_here = false;
-      while (todo_inline->length ())
+      for (fns1 = s1; fns1; fns1 = OVL_NEXT (fns1))
 	{
-	  cxx_binding *binding;
-
-	  scope = todo_inline->pop ();
-	  if (tree_vec_contains (seen_inline, scope))
-	    continue;
-	  vec_safe_push (seen_inline, scope);
-
-	  binding =
-	    cp_binding_level_find_binding_for_name (NAMESPACE_LEVEL (scope), name);
-	  if (binding)
-	    {
-	      ambiguous_decl (result, binding, flags);
-	      if (result->type || result->value)
-		found_here = true;
-	    }
+	  tree fn1 = OVL_CURRENT (fns1);
 
-	  for (usings = DECL_NAMESPACE_USING (scope); usings;
-	       usings = TREE_CHAIN (usings))
-	    if (!TREE_INDIRECT_USING (usings))
-	      {
-		if (is_associated_namespace (scope, TREE_PURPOSE (usings)))
-		  vec_safe_push (todo_inline, TREE_PURPOSE (usings));
-		else
-		  vec_safe_push (todo_maybe, TREE_PURPOSE (usings));
-	      }
+	  /* If the function from S2 is already in S1, there is no
+	     need to add it again.  For `extern "C"' functions, we
+	     might have two FUNCTION_DECLs for the same function, in
+	     different namespaces, but let's leave them in case
+	     they have different default arguments.  */
+	  if (fn1 == fn2)
+	    break;
 	}
 
-      if (found_here)
-	vec_safe_truncate (todo_maybe, 0);
-      else
-	while (vec_safe_length (todo_maybe))
-	  vec_safe_push (todo, todo_maybe->pop ());
+      /* If we exhausted all of the functions in S1, FN2 is new.  */
+      if (!fns1)
+	s1 = build_overload (fn2, s1);
     }
-  vec_free (todo);
-  vec_free (todo_maybe);
-  vec_free (todo_inline);
-  vec_free (seen);
-  vec_free (seen_inline);
-  timevar_stop (TV_NAME_LOOKUP);
-  return result->value != error_mark_node;
+  return s1;
 }
 
-/* Helper function for lookup_name_fuzzy.
-   Traverse binding level LVL, looking for good name matches for NAME
-   (and BM).  */
-static void
-consider_binding_level (tree name, best_match <tree, const char *> &bm,
-			cp_binding_level *lvl, bool look_within_fields,
-			enum lookup_name_fuzzy_kind kind)
-{
-  if (look_within_fields)
-    if (lvl->this_entity && TREE_CODE (lvl->this_entity) == RECORD_TYPE)
-      {
-	tree type = lvl->this_entity;
-	bool want_type_p = (kind == FUZZY_LOOKUP_TYPENAME);
-	tree best_matching_field
-	  = lookup_member_fuzzy (type, name, want_type_p);
-	if (best_matching_field)
-	  bm.consider (IDENTIFIER_POINTER (best_matching_field));
-      }
-
-  for (tree t = lvl->names; t; t = TREE_CHAIN (t))
-    {
-      tree d = t;
-
-      /* OVERLOADs or decls from using declaration are wrapped into
-	 TREE_LIST.  */
-      if (TREE_CODE (d) == TREE_LIST)
-	{
-	  d = TREE_VALUE (d);
-	  d = OVL_CURRENT (d);
-	}
+/* Returns TRUE iff OLD and NEW are the same entity.
 
-      /* Don't use bindings from implicitly declared functions,
-	 as they were likely misspellings themselves.  */
-      if (TREE_TYPE (d) == error_mark_node)
-	continue;
+   3 [basic]/3: An entity is a value, object, reference, function,
+   enumerator, type, class member, template, template specialization,
+   namespace, parameter pack, or this.
 
-      /* Skip anticipated decls of builtin functions.  */
-      if (TREE_CODE (d) == FUNCTION_DECL
-	  && DECL_BUILT_IN (d)
-	  && DECL_ANTICIPATED (d))
-	continue;
+   7.3.4 [namespace.udir]/4: If name lookup finds a declaration for a name
+   in two different namespaces, and the declarations do not declare the
+   same entity and do not declare functions, the use of the name is
+   ill-formed.  */
 
-      if (tree name = DECL_NAME (d))
-	/* Ignore internal names with spaces in them.  */
-	if (!strchr (IDENTIFIER_POINTER (name), ' '))
-	  bm.consider (IDENTIFIER_POINTER (name));
-    }
+static bool
+same_entity_p (tree one, tree two)
+{
+  if (one == two)
+    return true;
+  if (!one || !two)
+    return false;
+  if (TREE_CODE (one) == TYPE_DECL
+      && TREE_CODE (two) == TYPE_DECL
+      && same_type_p (TREE_TYPE (one), TREE_TYPE (two)))
+    return true;
+  return false;
 }
 
-/* Search for near-matches for NAME within the current bindings, and within
-   macro names, returning the best match as a const char *, or NULL if
-   no reasonable match is found.  */
+/* This should return an error not all definitions define functions.
+   It is not an error if we find two functions with exactly the
+   same signature, only if these are selected in overload resolution.
+   old is the current set of bindings, new_binding the freshly-found binding.
+   XXX Do we want to give *all* candidates in case of ambiguity?
+   XXX In what way should I treat extern declarations?
+   XXX I don't want to repeat the entire duplicate_decls here */
 
-const char *
-lookup_name_fuzzy (tree name, enum lookup_name_fuzzy_kind kind)
+static void
+ambiguous_decl (struct scope_binding *old, cxx_binding *new_binding, int flags)
 {
-  gcc_assert (TREE_CODE (name) == IDENTIFIER_NODE);
-
-  best_match <tree, const char *> bm (name);
-
-  cp_binding_level *lvl;
-  for (lvl = scope_chain->class_bindings; lvl; lvl = lvl->level_chain)
-    consider_binding_level (name, bm, lvl, true, kind);
-
-  for (lvl = current_binding_level; lvl; lvl = lvl->level_chain)
-    consider_binding_level (name, bm, lvl, false, kind);
+  tree val, type;
+  gcc_assert (old != NULL);
 
-  /* Consider macros: if the user misspelled a macro name e.g. "SOME_MACRO"
-     as:
-       x = SOME_OTHER_MACRO (y);
-     then "SOME_OTHER_MACRO" will survive to the frontend and show up
-     as a misspelled identifier.
+  /* Copy the type.  */
+  type = new_binding->type;
+  if (LOOKUP_NAMESPACES_ONLY (flags)
+      || (type && hidden_name_p (type) && !(flags & LOOKUP_HIDDEN)))
+    type = NULL_TREE;
 
-     Use the best distance so far so that a candidate is only set if
-     a macro is better than anything so far.  This allows early rejection
-     (without calculating the edit distance) of macro names that must have
-     distance >= bm.get_best_distance (), and means that we only get a
-     non-NULL result for best_macro_match if it's better than any of
-     the identifiers already checked.  */
-  best_macro_match bmm (name, bm.get_best_distance (), parse_in);
-  cpp_hashnode *best_macro = bmm.get_best_meaningful_candidate ();
-  /* If a macro is the closest so far to NAME, consider it.  */
-  if (best_macro)
-    bm.consider ((const char *)best_macro->ident.str);
+  /* Copy the value.  */
+  val = new_binding->value;
+  if (val)
+    {
+      if (!(flags & LOOKUP_HIDDEN))
+	val = remove_hidden_names (val);
+      if (val)
+	switch (TREE_CODE (val))
+	  {
+	  case TEMPLATE_DECL:
+	    /* If we expect types or namespaces, and not templates,
+	       or this is not a template class.  */
+	    if ((LOOKUP_QUALIFIERS_ONLY (flags)
+		 && !DECL_TYPE_TEMPLATE_P (val)))
+	      val = NULL_TREE;
+	    break;
+	  case TYPE_DECL:
+	    if (LOOKUP_NAMESPACES_ONLY (flags)
+		|| (type && (flags & LOOKUP_PREFER_TYPES)))
+	      val = NULL_TREE;
+	    break;
+	  case NAMESPACE_DECL:
+	    if (LOOKUP_TYPES_ONLY (flags))
+	      val = NULL_TREE;
+	    break;
+	  case FUNCTION_DECL:
+	    /* Ignore built-in functions that are still anticipated.  */
+	    if (LOOKUP_QUALIFIERS_ONLY (flags))
+	      val = NULL_TREE;
+	    break;
+	  default:
+	    if (LOOKUP_QUALIFIERS_ONLY (flags))
+	      val = NULL_TREE;
+	  }
+    }
 
-  /* Try the "starts_decl_specifier_p" keywords to detect
-     "singed" vs "signed" typos.  */
-  for (unsigned i = 0; i < num_c_common_reswords; i++)
+  /* If val is hidden, shift down any class or enumeration name.  */
+  if (!val)
     {
-      const c_common_resword *resword = &c_common_reswords[i];
-
-      if (kind == FUZZY_LOOKUP_TYPENAME)
-	if (!cp_keyword_starts_decl_specifier_p (resword->rid))
-	  continue;
-
-      tree resword_identifier = ridpointers [resword->rid];
-      if (!resword_identifier)
-	continue;
-      gcc_assert (TREE_CODE (resword_identifier) == IDENTIFIER_NODE);
+      val = type;
+      type = NULL_TREE;
+    }
 
-      /* Only consider reserved words that survived the
-	 filtering in init_reswords (e.g. for -std).  */
-      if (!C_IS_RESERVED_WORD (resword_identifier))
-	continue;
+  if (!old->value)
+    old->value = val;
+  else if (val && !same_entity_p (val, old->value))
+    {
+      if (is_overloaded_fn (old->value) && is_overloaded_fn (val))
+	old->value = merge_functions (old->value, val);
+      else
+	{
+	  old->value = tree_cons (NULL_TREE, old->value,
+				  build_tree_list (NULL_TREE, val));
+	  TREE_TYPE (old->value) = error_mark_node;
+	}
+    }
 
-      bm.consider (IDENTIFIER_POINTER (resword_identifier));
+  if (!old->type)
+    old->type = type;
+  else if (type && old->type != type)
+    {
+      old->type = tree_cons (NULL_TREE, old->type,
+			     build_tree_list (NULL_TREE, type));
+      TREE_TYPE (old->type) = error_mark_node;
     }
+}
 
-  return bm.get_best_meaningful_candidate ();
+/* Return the declarations that are members of the namespace NS.  */
+
+tree
+cp_namespace_decls (tree ns)
+{
+  return NAMESPACE_LEVEL (ns)->names;
 }
 
-/* Subroutine of outer_binding.
+/* Combine prefer_type and namespaces_only into flags.  */
 
-   Returns TRUE if BINDING is a binding to a template parameter of
-   SCOPE.  In that case SCOPE is the scope of a primary template
-   parameter -- in the sense of G++, i.e, a template that has its own
-   template header.
+static int
+lookup_flags (int prefer_type, int namespaces_only)
+{
+  if (namespaces_only)
+    return LOOKUP_PREFER_NAMESPACES;
+  if (prefer_type > 1)
+    return LOOKUP_PREFER_TYPES;
+  if (prefer_type > 0)
+    return LOOKUP_PREFER_BOTH;
+  return 0;
+}
 
-   Returns FALSE otherwise.  */
+/* Given a lookup that returned VAL, use FLAGS to decide if we want to
+   ignore it or not.  Subroutine of lookup_name_real and
+   lookup_type_scope.  */
 
 static bool
-binding_to_template_parms_of_scope_p (cxx_binding *binding,
-				      cp_binding_level *scope)
+qualify_lookup (tree val, int flags)
 {
-  tree binding_value, tmpl, tinfo;
-  int level;
-
-  if (!binding || !scope || !scope->this_entity)
+  if (val == NULL_TREE)
     return false;
-
-  binding_value = binding->value ?  binding->value : binding->type;
-  tinfo = get_template_info (scope->this_entity);
-
-  /* BINDING_VALUE must be a template parm.  */
-  if (binding_value == NULL_TREE
-      || (!DECL_P (binding_value)
-          || !DECL_TEMPLATE_PARM_P (binding_value)))
+  if ((flags & LOOKUP_PREFER_NAMESPACES) && TREE_CODE (val) == NAMESPACE_DECL)
+    return true;
+  if (flags & LOOKUP_PREFER_TYPES)
+    {
+      tree target_val = strip_using_decl (val);
+      if (TREE_CODE (target_val) == TYPE_DECL
+	  || TREE_CODE (target_val) == TEMPLATE_DECL)
+	return true;
+    }
+  if (flags & (LOOKUP_PREFER_NAMESPACES | LOOKUP_PREFER_TYPES))
     return false;
+  /* Look through lambda things that we shouldn't be able to see.  */
+  if (is_lambda_ignored_entity (val))
+    return false;
+  return true;
+}
 
-  /*  The level of BINDING_VALUE.  */
-  level =
-    template_type_parameter_p (binding_value)
-    ? TEMPLATE_PARM_LEVEL (TEMPLATE_TYPE_PARM_INDEX
-			 (TREE_TYPE (binding_value)))
-    : TEMPLATE_PARM_LEVEL (DECL_INITIAL (binding_value));
-
-  /* The template of the current scope, iff said scope is a primary
-     template.  */
-  tmpl = (tinfo
-	  && PRIMARY_TEMPLATE_P (TI_TEMPLATE (tinfo))
-	  ? TI_TEMPLATE (tinfo)
-	  : NULL_TREE);
+/* Given a lookup that returned VAL, decide if we want to ignore it or
+   not based on DECL_ANTICIPATED.  */
 
-  /* If the level of the parm BINDING_VALUE equals the depth of TMPL,
-     then BINDING_VALUE is a parameter of TMPL.  */
-  return (tmpl && level == TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl)));
+bool
+hidden_name_p (tree val)
+{
+  if (DECL_P (val)
+      && DECL_LANG_SPECIFIC (val)
+      && TYPE_FUNCTION_OR_TEMPLATE_DECL_P (val)
+      && DECL_ANTICIPATED (val))
+    return true;
+  if (TREE_CODE (val) == OVERLOAD)
+    {
+      for (tree o = val; o; o = OVL_CHAIN (o))
+	if (!hidden_name_p (OVL_FUNCTION (o)))
+	  return false;
+      return true;
+    }
+  return false;
 }
 
-/* Return the innermost non-namespace binding for NAME from a scope
-   containing BINDING, or, if BINDING is NULL, the current scope.
-   Please note that for a given template, the template parameters are
-   considered to be in the scope containing the current scope.
-   If CLASS_P is false, then class bindings are ignored.  */
+/* Remove any hidden declarations from a possibly overloaded set
+   of functions.  */
 
-cxx_binding *
-outer_binding (tree name,
-	       cxx_binding *binding,
-	       bool class_p)
+tree
+remove_hidden_names (tree fns)
 {
-  cxx_binding *outer;
-  cp_binding_level *scope;
-  cp_binding_level *outer_scope;
+  if (!fns)
+    return fns;
 
-  if (binding)
-    {
-      scope = binding->scope->level_chain;
-      outer = binding->previous;
-    }
-  else
+  if (DECL_P (fns) && hidden_name_p (fns))
+    fns = NULL_TREE;
+  else if (TREE_CODE (fns) == OVERLOAD)
     {
-      scope = current_binding_level;
-      outer = IDENTIFIER_BINDING (name);
-    }
-  outer_scope = outer ? outer->scope : NULL;
-
-  /* Because we create class bindings lazily, we might be missing a
-     class binding for NAME.  If there are any class binding levels
-     between the LAST_BINDING_LEVEL and the scope in which OUTER was
-     declared, we must lookup NAME in those class scopes.  */
-  if (class_p)
-    while (scope && scope != outer_scope && scope->kind != sk_namespace)
-      {
-	if (scope->kind == sk_class)
-	  {
-	    cxx_binding *class_binding;
+      tree o;
 
-	    class_binding = get_class_binding (name, scope);
-	    if (class_binding)
-	      {
-		/* Thread this new class-scope binding onto the
-		   IDENTIFIER_BINDING list so that future lookups
-		   find it quickly.  */
-		class_binding->previous = outer;
-		if (binding)
-		  binding->previous = class_binding;
-		else
-		  IDENTIFIER_BINDING (name) = class_binding;
-		return class_binding;
-	      }
-	  }
-	/* If we are in a member template, the template parms of the member
-	   template are considered to be inside the scope of the containing
-	   class, but within G++ the class bindings are all pushed between the
-	   template parms and the function body.  So if the outer binding is
-	   a template parm for the current scope, return it now rather than
-	   look for a class binding.  */
-	if (outer_scope && outer_scope->kind == sk_template_parms
-	    && binding_to_template_parms_of_scope_p (outer, scope))
-	  return outer;
+      for (o = fns; o; o = OVL_NEXT (o))
+	if (hidden_name_p (OVL_CURRENT (o)))
+	  break;
+      if (o)
+	{
+	  tree n = NULL_TREE;
 
-	scope = scope->level_chain;
-      }
+	  for (o = fns; o; o = OVL_NEXT (o))
+	    if (!hidden_name_p (OVL_CURRENT (o)))
+	      n = build_overload (OVL_CURRENT (o), n);
+	  fns = n;
+	}
+    }
 
-  return outer;
+  return fns;
 }
 
-/* Return the innermost block-scope or class-scope value binding for
-   NAME, or NULL_TREE if there is no such binding.  */
+/* Suggest alternatives for NAME, an IDENTIFIER_NODE for which name
+   lookup failed.  Search through all available namespaces and print out
+   possible candidates.  If no exact matches are found, and
+   SUGGEST_MISSPELLINGS is true, then also look for near-matches and
+   suggest the best near-match, if there is one.  */
 
-tree
-innermost_non_namespace_value (tree name)
+void
+suggest_alternatives_for (location_t location, tree name,
+			  bool suggest_misspellings)
 {
-  cxx_binding *binding;
-  binding = outer_binding (name, /*binding=*/NULL, /*class_p=*/true);
-  return binding ? binding->value : NULL_TREE;
-}
+  vec<tree> candidates = vNULL;
+  vec<tree> namespaces_to_search = vNULL;
+  int max_to_search = PARAM_VALUE (CXX_MAX_NAMESPACES_FOR_DIAGNOSTIC_HELP);
+  int n_searched = 0;
+  tree t;
+  unsigned ix;
+
+  namespaces_to_search.safe_push (global_namespace);
+
+  while (!namespaces_to_search.is_empty ()
+	 && n_searched < max_to_search)
+    {
+      tree scope = namespaces_to_search.pop ();
+      struct scope_binding binding = EMPTY_SCOPE_BINDING;
+      cp_binding_level *level = NAMESPACE_LEVEL (scope);
 
-/* Look up NAME in the current binding level and its superiors in the
-   namespace of variables, functions and typedefs.  Return a ..._DECL
-   node of some kind representing its definition if there is only one
-   such declaration, or return a TREE_LIST with all the overloaded
-   definitions if there are many, or return 0 if it is undefined.
-   Hidden name, either friend declaration or built-in function, are
-   not ignored.
+      /* Look in this namespace.  */
+      qualified_lookup_using_namespace (name, scope, &binding, 0);
 
-   If PREFER_TYPE is > 0, we prefer TYPE_DECLs or namespaces.
-   If PREFER_TYPE is > 1, we reject non-type decls (e.g. namespaces).
-   Otherwise we prefer non-TYPE_DECLs.
+      n_searched++;
 
-   If NONCLASS is nonzero, bindings in class scopes are ignored.  If
-   BLOCK_P is false, bindings in block scopes are ignored.  */
+      if (binding.value)
+	candidates.safe_push (binding.value);
 
-static tree
-lookup_name_real_1 (tree name, int prefer_type, int nonclass, bool block_p,
-		    int namespaces_only, int flags)
-{
-  cxx_binding *iter;
-  tree val = NULL_TREE;
+      /* Add child namespaces.  */
+      for (t = level->namespaces; t; t = DECL_CHAIN (t))
+	namespaces_to_search.safe_push (t);
+    }
 
-  query_oracle (name);
+  /* If we stopped before we could examine all namespaces, inform the
+     user.  Do this even if we don't have any candidates, since there
+     might be more candidates further down that we weren't able to
+     find.  */
+  if (n_searched >= max_to_search
+      && !namespaces_to_search.is_empty ())
+    inform (location,
+	    "maximum limit of %d namespaces searched for %qE",
+	    max_to_search, name);
 
-  /* Conversion operators are handled specially because ordinary
-     unqualified name lookup will not find template conversion
-     operators.  */
-  if (IDENTIFIER_TYPENAME_P (name))
-    {
-      cp_binding_level *level;
+  namespaces_to_search.release ();
 
-      for (level = current_binding_level;
-	   level && level->kind != sk_namespace;
-	   level = level->level_chain)
+  /* Nothing useful to report for NAME.  Report on likely misspellings,
+     or do nothing.  */
+  if (candidates.is_empty ())
+    {
+      if (suggest_misspellings)
 	{
-	  tree class_type;
-	  tree operators;
+	  const char *fuzzy_name = lookup_name_fuzzy (name, FUZZY_LOOKUP_NAME);
+	  if (fuzzy_name)
+	    {
+	      gcc_rich_location richloc (location);
+	      richloc.add_fixit_replace (fuzzy_name);
+	      inform_at_rich_loc (&richloc, "suggested alternative: %qs",
+				  fuzzy_name);
+	    }
+	}
+      return;
+    }
 
-	  /* A conversion operator can only be declared in a class
-	     scope.  */
-	  if (level->kind != sk_class)
-	    continue;
+  inform_n (location, candidates.length (),
+	    "suggested alternative:",
+	    "suggested alternatives:");
 
-	  /* Lookup the conversion operator in the class.  */
-	  class_type = level->this_entity;
-	  operators = lookup_fnfields (class_type, name, /*protect=*/0);
-	  if (operators)
-	    return operators;
-	}
+  FOR_EACH_VEC_ELT (candidates, ix, t)
+    inform (location_of (t), "  %qE", t);
 
-      return NULL_TREE;
-    }
+  candidates.release ();
+}
 
-  flags |= lookup_flags (prefer_type, namespaces_only);
+/* Subroutine of maybe_suggest_missing_header for handling unrecognized names
+   for some of the most common names within "std::".
+   Given non-NULL NAME, a name for lookup within "std::", return the header
+   name defining it within the C++ Standard Library (without '<' and '>'),
+   or NULL.  */
 
-  /* First, look in non-namespace scopes.  */
+static const char *
+get_std_name_hint (const char *name)
+{
+  struct std_name_hint
+  {
+    const char *name;
+    const char *header;
+  };
+  static const std_name_hint hints[] = {
+    /* <array>.  */
+    {"array", "array"}, // C++11
+    /* <deque>.  */
+    {"deque", "deque"},
+    /* <forward_list>.  */
+    {"forward_list", "forward_list"},  // C++11
+    /* <fstream>.  */
+    {"basic_filebuf", "fstream"},
+    {"basic_ifstream", "fstream"},
+    {"basic_ofstream", "fstream"},
+    {"basic_fstream", "fstream"},
+    /* <iostream>.  */
+    {"cin", "iostream"},
+    {"cout", "iostream"},
+    {"cerr", "iostream"},
+    {"clog", "iostream"},
+    {"wcin", "iostream"},
+    {"wcout", "iostream"},
+    {"wclog", "iostream"},
+    /* <list>.  */
+    {"list", "list"},
+    /* <map>.  */
+    {"map", "map"},
+    {"multimap", "map"},
+    /* <queue>.  */
+    {"queue", "queue"},
+    {"priority_queue", "queue"},
+    /* <ostream>.  */
+    {"ostream", "ostream"},
+    {"wostream", "ostream"},
+    {"ends", "ostream"},
+    {"flush", "ostream"},
+    {"endl", "ostream"},
+    /* <set>.  */
+    {"set", "set"},
+    {"multiset", "set"},
+    /* <sstream>.  */
+    {"basic_stringbuf", "sstream"},
+    {"basic_istringstream", "sstream"},
+    {"basic_ostringstream", "sstream"},
+    {"basic_stringstream", "sstream"},
+    /* <stack>.  */
+    {"stack", "stack"},
+    /* <string>.  */
+    {"string", "string"},
+    {"wstring", "string"},
+    {"u16string", "string"},
+    {"u32string", "string"},
+    /* <unordered_map>.  */
+    {"unordered_map", "unordered_map"}, // C++11
+    {"unordered_multimap", "unordered_map"}, // C++11
+    /* <unordered_set>.  */
+    {"unordered_set", "unordered_set"}, // C++11
+    {"unordered_multiset", "unordered_set"}, // C++11
+    /* <vector>.  */
+    {"vector", "vector"},
+  };
+  const size_t num_hints = sizeof (hints) / sizeof (hints[0]);
+  for (size_t i = 0; i < num_hints; i++)
+    {
+      if (0 == strcmp (name, hints[i].name))
+	return hints[i].header;
+    }
+  return NULL;
+}
 
-  if (current_class_type == NULL_TREE)
-    nonclass = 1;
+/* Subroutine of suggest_alternative_in_explicit_scope, for use when we have no
+   suggestions to offer.
+   If SCOPE is the "std" namespace, then suggest pertinent header
+   files for NAME.  */
 
-  if (block_p || !nonclass)
-    for (iter = outer_binding (name, NULL, !nonclass);
-	 iter;
-	 iter = outer_binding (name, iter, !nonclass))
-      {
-	tree binding;
+static void
+maybe_suggest_missing_header (location_t location, tree name, tree scope)
+{
+  if (scope == NULL_TREE)
+    return;
+  if (TREE_CODE (scope) != NAMESPACE_DECL)
+    return;
+  /* We only offer suggestions for the "std" namespace.  */
+  if (scope != std_node)
+    return;
+  gcc_assert (TREE_CODE (name) == IDENTIFIER_NODE);
 
-	/* Skip entities we don't want.  */
-	if (LOCAL_BINDING_P (iter) ? !block_p : nonclass)
-	  continue;
+  const char *name_str = IDENTIFIER_POINTER (name);
+  const char *header_hint = get_std_name_hint (name_str);
+  if (header_hint)
+    inform (location,
+	    "%<std::%s%> is defined in header %<<%s>%>;"
+	    " did you forget to %<#include <%s>%>?",
+	    name_str, header_hint, header_hint);
+}
 
-	/* If this is the kind of thing we're looking for, we're done.  */
-	if (qualify_lookup (iter->value, flags))
-	  binding = iter->value;
-	else if ((flags & LOOKUP_PREFER_TYPES)
-		 && qualify_lookup (iter->type, flags))
-	  binding = iter->type;
-	else
-	  binding = NULL_TREE;
+/* Look for alternatives for NAME, an IDENTIFIER_NODE for which name
+   lookup failed within the explicitly provided SCOPE.  Suggest the
+   the best meaningful candidates (if any) as a fix-it hint.
+   Return true iff a suggestion was provided.  */
 
-	if (binding)
-	  {
-	    if (hidden_name_p (binding))
-	      {
-		/* A non namespace-scope binding can only be hidden in the
-		   presence of a local class, due to friend declarations.
+bool
+suggest_alternative_in_explicit_scope (location_t location, tree name,
+				       tree scope)
+{
+  /* Resolve any namespace aliases.  */
+  scope = ORIGINAL_NAMESPACE (scope);
 
-		   In particular, consider:
+  cp_binding_level *level = NAMESPACE_LEVEL (scope);
 
-		   struct C;
-		   void f() {
-		     struct A {
-		       friend struct B;
-		       friend struct C;
-		       void g() {
-		         B* b; // error: B is hidden
-			 C* c; // OK, finds ::C
-		       } 
-		     };
-		     B *b;  // error: B is hidden
-		     C *c;  // OK, finds ::C
-		     struct B {};
-		     B *bb; // OK
-		   }
+  best_match <tree, const char *> bm (name);
+  consider_binding_level (name, bm, level, false, FUZZY_LOOKUP_NAME);
 
-		   The standard says that "B" is a local class in "f"
-		   (but not nested within "A") -- but that name lookup
-		   for "B" does not find this declaration until it is
-		   declared directly with "f".
+  /* See if we have a good suggesion for the user.  */
+  const char *fuzzy_name = bm.get_best_meaningful_candidate ();
+  if (fuzzy_name)
+    {
+      gcc_rich_location richloc (location);
+      richloc.add_fixit_replace (fuzzy_name);
+      inform_at_rich_loc (&richloc, "suggested alternative: %qs",
+			  fuzzy_name);
+      return true;
+    }
+  else
+    maybe_suggest_missing_header (location, name, scope);
 
-		   In particular:
+  return false;
+}
 
-		   [class.friend]
+/* Unscoped lookup of a global: iterate over current namespaces,
+   considering using-directives.  */
 
-		   If a friend declaration appears in a local class and
-		   the name specified is an unqualified name, a prior
-		   declaration is looked up without considering scopes
-		   that are outside the innermost enclosing non-class
-		   scope. For a friend function declaration, if there is
-		   no prior declaration, the program is ill-formed. For a
-		   friend class declaration, if there is no prior
-		   declaration, the class that is specified belongs to the
-		   innermost enclosing non-class scope, but if it is
-		   subsequently referenced, its name is not found by name
-		   lookup until a matching declaration is provided in the
-		   innermost enclosing nonclass scope.
+static tree
+unqualified_namespace_lookup_1 (tree name, int flags)
+{
+  tree initial = current_decl_namespace ();
+  tree scope = initial;
+  tree siter;
+  cp_binding_level *level;
+  tree val = NULL_TREE;
 
-		   So just keep looking for a non-hidden binding.
-		*/
-		gcc_assert (TREE_CODE (binding) == TYPE_DECL);
-		continue;
-	      }
-	    val = binding;
-	    break;
-	  }
-      }
+  for (; !val; scope = CP_DECL_CONTEXT (scope))
+    {
+      struct scope_binding binding = EMPTY_SCOPE_BINDING;
+      cxx_binding *b =
+	 cp_binding_level_find_binding_for_name (NAMESPACE_LEVEL (scope), name);
 
-  /* Now lookup in namespace scopes.  */
-  if (!val)
-    val = unqualified_namespace_lookup (name, flags);
+      if (b)
+	ambiguous_decl (&binding, b, flags);
 
-  /* Anticipated built-ins and friends aren't found by normal lookup.  */
-  if (val && !(flags & LOOKUP_HIDDEN))
-    val = remove_hidden_names (val);
+      /* Add all _DECLs seen through local using-directives.  */
+      for (level = current_binding_level;
+	   level->kind != sk_namespace;
+	   level = level->level_chain)
+	if (!lookup_using_namespace (name, &binding, level->using_directives,
+				     scope, flags))
+	  /* Give up because of error.  */
+	  return error_mark_node;
 
-  /* If we have a single function from a using decl, pull it out.  */
-  if (val && TREE_CODE (val) == OVERLOAD && !really_overloaded_fn (val))
-    val = OVL_FUNCTION (val);
+      /* Add all _DECLs seen through global using-directives.  */
+      /* XXX local and global using lists should work equally.  */
+      siter = initial;
+      while (1)
+	{
+	  if (!lookup_using_namespace (name, &binding,
+				       DECL_NAMESPACE_USING (siter),
+				       scope, flags))
+	    /* Give up because of error.  */
+	    return error_mark_node;
+	  if (siter == scope) break;
+	  siter = CP_DECL_CONTEXT (siter);
+	}
 
+      val = binding.value;
+      if (scope == global_namespace)
+	break;
+    }
   return val;
 }
 
-/* Wrapper for lookup_name_real_1.  */
+/* Wrapper for unqualified_namespace_lookup_1.  */
 
-tree
-lookup_name_real (tree name, int prefer_type, int nonclass, bool block_p,
-		  int namespaces_only, int flags)
+static tree
+unqualified_namespace_lookup (tree name, int flags)
 {
   tree ret;
   bool subtime = timevar_cond_start (TV_NAME_LOOKUP);
-  ret = lookup_name_real_1 (name, prefer_type, nonclass, block_p,
-			    namespaces_only, flags);
+  ret = unqualified_namespace_lookup_1 (name, flags);
   timevar_cond_stop (TV_NAME_LOOKUP, subtime);
   return ret;
 }
 
-tree
-lookup_name_nonclass (tree name)
-{
-  return lookup_name_real (name, 0, 1, /*block_p=*/true, 0, 0);
-}
+/* Look up NAME (an IDENTIFIER_NODE) in SCOPE (either a NAMESPACE_DECL
+   or a class TYPE).
 
-tree
-lookup_function_nonclass (tree name, vec<tree, va_gc> *args, bool block_p)
-{
-  return
-    lookup_arg_dependent (name,
-			  lookup_name_real (name, 0, 1, block_p, 0, 0),
-			  args);
-}
+   If PREFER_TYPE is > 0, we only return TYPE_DECLs or namespaces.
+   If PREFER_TYPE is > 1, we only return TYPE_DECLs.
 
-tree
-lookup_name (tree name)
-{
-  return lookup_name_real (name, 0, 0, /*block_p=*/true, 0, 0);
-}
+   Returns a DECL (or OVERLOAD, or BASELINK) representing the
+   declaration found.  If no suitable declaration can be found,
+   ERROR_MARK_NODE is returned.  If COMPLAIN is true and SCOPE is
+   neither a class-type nor a namespace a diagnostic is issued.  */
 
 tree
-lookup_name_prefer_type (tree name, int prefer_type)
+lookup_qualified_name (tree scope, tree name, int prefer_type, bool complain,
+		       bool find_hidden)
 {
-  return lookup_name_real (name, prefer_type, 0, /*block_p=*/true, 0, 0);
+  tree t = NULL_TREE;
+
+  if (TREE_CODE (scope) == NAMESPACE_DECL)
+    {
+      struct scope_binding binding = EMPTY_SCOPE_BINDING;
+
+      int flags = lookup_flags (prefer_type, /*namespaces_only*/false);
+      if (find_hidden)
+	flags |= LOOKUP_HIDDEN;
+      if (qualified_lookup_using_namespace (name, scope, &binding, flags))
+	t = binding.value;
+    }
+  else if (cxx_dialect != cxx98 && TREE_CODE (scope) == ENUMERAL_TYPE)
+    t = lookup_enumerator (scope, name);
+  else if (is_class_type (scope, complain))
+    t = lookup_member (scope, name, 2, prefer_type, tf_warning_or_error);
+
+  if (!t)
+    return error_mark_node;
+  return t;
 }
 
-/* Look up NAME for type used in elaborated name specifier in
-   the scopes given by SCOPE.  SCOPE can be either TS_CURRENT or
-   TS_WITHIN_ENCLOSING_NON_CLASS.  Although not implied by the
-   name, more scopes are checked if cleanup or template parameter
-   scope is encountered.
+/* Subroutine of unqualified_namespace_lookup:
+   Add the bindings of NAME in used namespaces to VAL.
+   We are currently looking for names in namespace SCOPE, so we
+   look through USINGS for using-directives of namespaces
+   which have SCOPE as a common ancestor with the current scope.
+   Returns false on errors.  */
 
-   Unlike lookup_name_real, we make sure that NAME is actually
-   declared in the desired scope, not from inheritance, nor using
-   directive.  For using declaration, there is DR138 still waiting
-   to be resolved.  Hidden name coming from an earlier friend
-   declaration is also returned.
+static bool
+lookup_using_namespace (tree name, struct scope_binding *val,
+			tree usings, tree scope, int flags)
+{
+  tree iter;
+  bool subtime = timevar_cond_start (TV_NAME_LOOKUP);
+  /* Iterate over all used namespaces in current, searching for using
+     directives of scope.  */
+  for (iter = usings; iter; iter = TREE_CHAIN (iter))
+    if (TREE_VALUE (iter) == scope)
+      {
+	tree used = ORIGINAL_NAMESPACE (TREE_PURPOSE (iter));
+	cxx_binding *val1 =
+	  cp_binding_level_find_binding_for_name (NAMESPACE_LEVEL (used), name);
+	/* Resolve ambiguities.  */
+	if (val1)
+	  ambiguous_decl (val, val1, flags);
+      }
+  timevar_cond_stop (TV_NAME_LOOKUP, subtime);
+  return val->value != error_mark_node;
+}
 
-   A TYPE_DECL best matching the NAME is returned.  Catching error
-   and issuing diagnostics are caller's responsibility.  */
+/* Returns true iff VEC contains TARGET.  */
 
-static tree
-lookup_type_scope_1 (tree name, tag_scope scope)
+static bool
+tree_vec_contains (vec<tree, va_gc> *vec, tree target)
 {
-  cxx_binding *iter = NULL;
-  tree val = NULL_TREE;
+  unsigned int i;
+  tree elt;
+  FOR_EACH_VEC_SAFE_ELT (vec,i,elt)
+    if (elt == target)
+      return true;
+  return false;
+}
 
-  /* Look in non-namespace scope first.  */
-  if (current_binding_level->kind != sk_namespace)
-    iter = outer_binding (name, NULL, /*class_p=*/ true);
-  for (; iter; iter = outer_binding (name, iter, /*class_p=*/ true))
-    {
-      /* Check if this is the kind of thing we're looking for.
-	 If SCOPE is TS_CURRENT, also make sure it doesn't come from
-	 base class.  For ITER->VALUE, we can simply use
-	 INHERITED_VALUE_BINDING_P.  For ITER->TYPE, we have to use
-	 our own check.
+/* [namespace.qual]
+   Accepts the NAME to lookup and its qualifying SCOPE.
+   Returns the name/type pair found into the cxx_binding *RESULT,
+   or false on error.  */
 
-	 We check ITER->TYPE before ITER->VALUE in order to handle
-	   typedef struct C {} C;
-	 correctly.  */
+static bool
+qualified_lookup_using_namespace (tree name, tree scope,
+				  struct scope_binding *result, int flags)
+{
+  /* Maintain a list of namespaces visited...  */
+  vec<tree, va_gc> *seen = NULL;
+  vec<tree, va_gc> *seen_inline = NULL;
+  /* ... and a list of namespace yet to see.  */
+  vec<tree, va_gc> *todo = NULL;
+  vec<tree, va_gc> *todo_maybe = NULL;
+  vec<tree, va_gc> *todo_inline = NULL;
+  tree usings;
+  timevar_start (TV_NAME_LOOKUP);
+  /* Look through namespace aliases.  */
+  scope = ORIGINAL_NAMESPACE (scope);
 
-      if (qualify_lookup (iter->type, LOOKUP_PREFER_TYPES)
-	  && (scope != ts_current
-	      || LOCAL_BINDING_P (iter)
-	      || DECL_CONTEXT (iter->type) == iter->scope->this_entity))
-	val = iter->type;
-      else if ((scope != ts_current
-		|| !INHERITED_VALUE_BINDING_P (iter))
-	       && qualify_lookup (iter->value, LOOKUP_PREFER_TYPES))
-	val = iter->value;
+  query_oracle (name);
 
-      if (val)
-	break;
-    }
+  /* Algorithm: Starting with SCOPE, walk through the set of used
+     namespaces.  For each used namespace, look through its inline
+     namespace set for any bindings and usings.  If no bindings are
+     found, add any usings seen to the set of used namespaces.  */
+  vec_safe_push (todo, scope);
 
-  /* Look in namespace scope.  */
-  if (!val)
+  while (todo->length ())
     {
-      iter = cp_binding_level_find_binding_for_name
-	       (NAMESPACE_LEVEL (current_decl_namespace ()), name);
+      bool found_here;
+      scope = todo->pop ();
+      if (tree_vec_contains (seen, scope))
+	continue;
+      vec_safe_push (seen, scope);
+      vec_safe_push (todo_inline, scope);
 
-      if (iter)
+      found_here = false;
+      while (todo_inline->length ())
 	{
-	  /* If this is the kind of thing we're looking for, we're done.  */
-	  if (qualify_lookup (iter->type, LOOKUP_PREFER_TYPES))
-	    val = iter->type;
-	  else if (qualify_lookup (iter->value, LOOKUP_PREFER_TYPES))
-	    val = iter->value;
-	}
+	  cxx_binding *binding;
 
-    }
+	  scope = todo_inline->pop ();
+	  if (tree_vec_contains (seen_inline, scope))
+	    continue;
+	  vec_safe_push (seen_inline, scope);
 
-  /* Type found, check if it is in the allowed scopes, ignoring cleanup
-     and template parameter scopes.  */
-  if (val)
-    {
-      cp_binding_level *b = current_binding_level;
-      while (b)
-	{
-	  if (iter->scope == b)
-	    return val;
+	  binding =
+	    cp_binding_level_find_binding_for_name (NAMESPACE_LEVEL (scope), name);
+	  if (binding)
+	    {
+	      ambiguous_decl (result, binding, flags);
+	      if (result->type || result->value)
+		found_here = true;
+	    }
 
-	  if (b->kind == sk_cleanup || b->kind == sk_template_parms
-	      || b->kind == sk_function_parms)
-	    b = b->level_chain;
-	  else if (b->kind == sk_class
-		   && scope == ts_within_enclosing_non_class)
-	    b = b->level_chain;
-	  else
-	    break;
+	  for (usings = DECL_NAMESPACE_USING (scope); usings;
+	       usings = TREE_CHAIN (usings))
+	    if (!TREE_INDIRECT_USING (usings))
+	      {
+		if (is_associated_namespace (scope, TREE_PURPOSE (usings)))
+		  vec_safe_push (todo_inline, TREE_PURPOSE (usings));
+		else
+		  vec_safe_push (todo_maybe, TREE_PURPOSE (usings));
+	      }
 	}
-    }
-
-  return NULL_TREE;
-}
- 
-/* Wrapper for lookup_type_scope_1.  */
 
-tree
-lookup_type_scope (tree name, tag_scope scope)
-{
-  tree ret;
-  bool subtime = timevar_cond_start (TV_NAME_LOOKUP);
-  ret = lookup_type_scope_1 (name, scope);
-  timevar_cond_stop (TV_NAME_LOOKUP, subtime);
-  return ret;
+      if (found_here)
+	vec_safe_truncate (todo_maybe, 0);
+      else
+	while (vec_safe_length (todo_maybe))
+	  vec_safe_push (todo, todo_maybe->pop ());
+    }
+  vec_free (todo);
+  vec_free (todo_maybe);
+  vec_free (todo_inline);
+  vec_free (seen);
+  vec_free (seen_inline);
+  timevar_stop (TV_NAME_LOOKUP);
+  return result->value != error_mark_node;
 }
 
-
-/* Similar to `lookup_name' but look only in the innermost non-class
-   binding level.  */
-
-static tree
-lookup_name_innermost_nonclass_level_1 (tree name)
+/* Helper function for lookup_name_fuzzy.
+   Traverse binding level LVL, looking for good name matches for NAME
+   (and BM).  */
+static void
+consider_binding_level (tree name, best_match <tree, const char *> &bm,
+			cp_binding_level *lvl, bool look_within_fields,
+			enum lookup_name_fuzzy_kind kind)
 {
-  cp_binding_level *b;
-  tree t = NULL_TREE;
-
-  b = innermost_nonclass_level ();
+  if (look_within_fields)
+    if (lvl->this_entity && TREE_CODE (lvl->this_entity) == RECORD_TYPE)
+      {
+	tree type = lvl->this_entity;
+	bool want_type_p = (kind == FUZZY_LOOKUP_TYPENAME);
+	tree best_matching_field
+	  = lookup_member_fuzzy (type, name, want_type_p);
+	if (best_matching_field)
+	  bm.consider (IDENTIFIER_POINTER (best_matching_field));
+      }
 
-  if (b->kind == sk_namespace)
+  for (tree t = lvl->names; t; t = TREE_CHAIN (t))
     {
-      t = IDENTIFIER_NAMESPACE_VALUE (name);
+      tree d = t;
 
-      /* extern "C" function() */
-      if (t != NULL_TREE && TREE_CODE (t) == TREE_LIST)
-	t = TREE_VALUE (t);
-    }
-  else if (IDENTIFIER_BINDING (name)
-	   && LOCAL_BINDING_P (IDENTIFIER_BINDING (name)))
-    {
-      cxx_binding *binding;
-      binding = IDENTIFIER_BINDING (name);
-      while (1)
+      /* OVERLOADs or decls from using declaration are wrapped into
+	 TREE_LIST.  */
+      if (TREE_CODE (d) == TREE_LIST)
 	{
-	  if (binding->scope == b
-	      && !(VAR_P (binding->value)
-		   && DECL_DEAD_FOR_LOCAL (binding->value)))
-	    return binding->value;
-
-	  if (b->kind == sk_cleanup)
-	    b = b->level_chain;
-	  else
-	    break;
+	  d = TREE_VALUE (d);
+	  d = OVL_CURRENT (d);
 	}
-    }
 
-  return t;
-}
+      /* Don't use bindings from implicitly declared functions,
+	 as they were likely misspellings themselves.  */
+      if (TREE_TYPE (d) == error_mark_node)
+	continue;
 
-/* Wrapper for lookup_name_innermost_nonclass_level_1.  */
+      /* Skip anticipated decls of builtin functions.  */
+      if (TREE_CODE (d) == FUNCTION_DECL
+	  && DECL_BUILT_IN (d)
+	  && DECL_ANTICIPATED (d))
+	continue;
 
-tree
-lookup_name_innermost_nonclass_level (tree name)
-{
-  tree ret;
-  bool subtime = timevar_cond_start (TV_NAME_LOOKUP);
-  ret = lookup_name_innermost_nonclass_level_1 (name);
-  timevar_cond_stop (TV_NAME_LOOKUP, subtime);
-  return ret;
+      if (tree name = DECL_NAME (d))
+	/* Ignore internal names with spaces in them.  */
+	if (!strchr (IDENTIFIER_POINTER (name), ' '))
+	  bm.consider (IDENTIFIER_POINTER (name));
+    }
 }
 
+/* Search for near-matches for NAME within the current bindings, and within
+   macro names, returning the best match as a const char *, or NULL if
+   no reasonable match is found.  */
 
-/* Returns true iff DECL is a block-scope extern declaration of a function
-   or variable.  */
-
-bool
-is_local_extern (tree decl)
+const char *
+lookup_name_fuzzy (tree name, enum lookup_name_fuzzy_kind kind)
 {
-  cxx_binding *binding;
+  gcc_assert (TREE_CODE (name) == IDENTIFIER_NODE);
 
-  /* For functions, this is easy.  */
-  if (TREE_CODE (decl) == FUNCTION_DECL)
-    return DECL_LOCAL_FUNCTION_P (decl);
+  best_match <tree, const char *> bm (name);
 
-  if (!VAR_P (decl))
-    return false;
-  if (!current_function_decl)
-    return false;
+  cp_binding_level *lvl;
+  for (lvl = scope_chain->class_bindings; lvl; lvl = lvl->level_chain)
+    consider_binding_level (name, bm, lvl, true, kind);
 
-  /* For variables, this is not easy.  We need to look at the binding stack
-     for the identifier to see whether the decl we have is a local.  */
-  for (binding = IDENTIFIER_BINDING (DECL_NAME (decl));
-       binding && binding->scope->kind != sk_namespace;
-       binding = binding->previous)
-    if (binding->value == decl)
-      return LOCAL_BINDING_P (binding);
+  for (lvl = current_binding_level; lvl; lvl = lvl->level_chain)
+    consider_binding_level (name, bm, lvl, false, kind);
 
-  return false;
-}
+  /* Consider macros: if the user misspelled a macro name e.g. "SOME_MACRO"
+     as:
+       x = SOME_OTHER_MACRO (y);
+     then "SOME_OTHER_MACRO" will survive to the frontend and show up
+     as a misspelled identifier.
 
-/* Like lookup_name_innermost_nonclass_level, but for types.  */
+     Use the best distance so far so that a candidate is only set if
+     a macro is better than anything so far.  This allows early rejection
+     (without calculating the edit distance) of macro names that must have
+     distance >= bm.get_best_distance (), and means that we only get a
+     non-NULL result for best_macro_match if it's better than any of
+     the identifiers already checked.  */
+  best_macro_match bmm (name, bm.get_best_distance (), parse_in);
+  cpp_hashnode *best_macro = bmm.get_best_meaningful_candidate ();
+  /* If a macro is the closest so far to NAME, consider it.  */
+  if (best_macro)
+    bm.consider ((const char *)best_macro->ident.str);
 
-static tree
-lookup_type_current_level (tree name)
-{
-  tree t = NULL_TREE;
+  /* Try the "starts_decl_specifier_p" keywords to detect
+     "singed" vs "signed" typos.  */
+  for (unsigned i = 0; i < num_c_common_reswords; i++)
+    {
+      const c_common_resword *resword = &c_common_reswords[i];
 
-  timevar_start (TV_NAME_LOOKUP);
-  gcc_assert (current_binding_level->kind != sk_namespace);
+      if (kind == FUZZY_LOOKUP_TYPENAME)
+	if (!cp_keyword_starts_decl_specifier_p (resword->rid))
+	  continue;
 
-  if (REAL_IDENTIFIER_TYPE_VALUE (name) != NULL_TREE
-      && REAL_IDENTIFIER_TYPE_VALUE (name) != global_type_node)
-    {
-      cp_binding_level *b = current_binding_level;
-      while (1)
-	{
-	  if (purpose_member (name, b->type_shadowed))
-	    {
-	      t = REAL_IDENTIFIER_TYPE_VALUE (name);
-	      break;
-	    }
-	  if (b->kind == sk_cleanup)
-	    b = b->level_chain;
-	  else
-	    break;
-	}
-    }
+      tree resword_identifier = ridpointers [resword->rid];
+      if (!resword_identifier)
+	continue;
+      gcc_assert (TREE_CODE (resword_identifier) == IDENTIFIER_NODE);
 
-  timevar_stop (TV_NAME_LOOKUP);
-  return t;
-}
+      /* Only consider reserved words that survived the
+	 filtering in init_reswords (e.g. for -std).  */
+      if (!C_IS_RESERVED_WORD (resword_identifier))
+	continue;
 
-/* [basic.lookup.koenig] */
-/* A nonzero return value in the functions below indicates an error.  */
+      bm.consider (IDENTIFIER_POINTER (resword_identifier));
+    }
+
+  return bm.get_best_meaningful_candidate ();
+}
 
-struct arg_lookup
-{
-  tree name;
-  vec<tree, va_gc> *args;
-  vec<tree, va_gc> *namespaces;
-  vec<tree, va_gc> *classes;
-  tree functions;
-  hash_set<tree> *fn_set;
-};
+/* Subroutine of outer_binding.
 
-static bool arg_assoc (struct arg_lookup*, tree);
-static bool arg_assoc_args (struct arg_lookup*, tree);
-static bool arg_assoc_args_vec (struct arg_lookup*, vec<tree, va_gc> *);
-static bool arg_assoc_type (struct arg_lookup*, tree);
-static bool add_function (struct arg_lookup *, tree);
-static bool arg_assoc_namespace (struct arg_lookup *, tree);
-static bool arg_assoc_class_only (struct arg_lookup *, tree);
-static bool arg_assoc_bases (struct arg_lookup *, tree);
-static bool arg_assoc_class (struct arg_lookup *, tree);
-static bool arg_assoc_template_arg (struct arg_lookup*, tree);
+   Returns TRUE if BINDING is a binding to a template parameter of
+   SCOPE.  In that case SCOPE is the scope of a primary template
+   parameter -- in the sense of G++, i.e, a template that has its own
+   template header.
 
-/* Add a function to the lookup structure.
-   Returns true on error.  */
+   Returns FALSE otherwise.  */
 
 static bool
-add_function (struct arg_lookup *k, tree fn)
+binding_to_template_parms_of_scope_p (cxx_binding *binding,
+				      cp_binding_level *scope)
 {
-  if (!is_overloaded_fn (fn))
-    /* All names except those of (possibly overloaded) functions and
-       function templates are ignored.  */;
-  else if (k->fn_set && k->fn_set->add (fn))
-    /* It's already in the list.  */;
-  else if (!k->functions && TREE_CODE (fn) != TEMPLATE_DECL)
-    k->functions = fn;
-  else if (fn == k->functions)
-    ;
-  else
-    {
-      k->functions = build_overload (fn, k->functions);
-      if (TREE_CODE (k->functions) == OVERLOAD)
-	OVL_ARG_DEPENDENT (k->functions) = true;
-    }
+  tree binding_value, tmpl, tinfo;
+  int level;
 
-  return false;
+  if (!binding || !scope || !scope->this_entity)
+    return false;
+
+  binding_value = binding->value ?  binding->value : binding->type;
+  tinfo = get_template_info (scope->this_entity);
+
+  /* BINDING_VALUE must be a template parm.  */
+  if (binding_value == NULL_TREE
+      || (!DECL_P (binding_value)
+          || !DECL_TEMPLATE_PARM_P (binding_value)))
+    return false;
+
+  /*  The level of BINDING_VALUE.  */
+  level =
+    template_type_parameter_p (binding_value)
+    ? TEMPLATE_PARM_LEVEL (TEMPLATE_TYPE_PARM_INDEX
+			 (TREE_TYPE (binding_value)))
+    : TEMPLATE_PARM_LEVEL (DECL_INITIAL (binding_value));
+
+  /* The template of the current scope, iff said scope is a primary
+     template.  */
+  tmpl = (tinfo
+	  && PRIMARY_TEMPLATE_P (TI_TEMPLATE (tinfo))
+	  ? TI_TEMPLATE (tinfo)
+	  : NULL_TREE);
+
+  /* If the level of the parm BINDING_VALUE equals the depth of TMPL,
+     then BINDING_VALUE is a parameter of TMPL.  */
+  return (tmpl && level == TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl)));
 }
 
-/* Returns true iff CURRENT has declared itself to be an associated
-   namespace of SCOPE via a strong using-directive (or transitive chain
-   thereof).  Both are namespaces.  */
+/* Return the innermost non-namespace binding for NAME from a scope
+   containing BINDING, or, if BINDING is NULL, the current scope.
+   Please note that for a given template, the template parameters are
+   considered to be in the scope containing the current scope.
+   If CLASS_P is false, then class bindings are ignored.  */
 
-bool
-is_associated_namespace (tree current, tree scope)
+cxx_binding *
+outer_binding (tree name,
+	       cxx_binding *binding,
+	       bool class_p)
 {
-  vec<tree, va_gc> *seen = make_tree_vector ();
-  vec<tree, va_gc> *todo = make_tree_vector ();
-  tree t;
-  bool ret;
+  cxx_binding *outer;
+  cp_binding_level *scope;
+  cp_binding_level *outer_scope;
 
-  while (1)
+  if (binding)
     {
-      if (scope == current)
-	{
-	  ret = true;
-	  break;
-	}
-      vec_safe_push (seen, scope);
-      for (t = DECL_NAMESPACE_ASSOCIATIONS (scope); t; t = TREE_CHAIN (t))
-	if (!vec_member (TREE_PURPOSE (t), seen))
-	  vec_safe_push (todo, TREE_PURPOSE (t));
-      if (!todo->is_empty ())
-	{
-	  scope = todo->last ();
-	  todo->pop ();
-	}
-      else
-	{
-	  ret = false;
-	  break;
-	}
+      scope = binding->scope->level_chain;
+      outer = binding->previous;
+    }
+  else
+    {
+      scope = current_binding_level;
+      outer = IDENTIFIER_BINDING (name);
     }
+  outer_scope = outer ? outer->scope : NULL;
 
-  release_tree_vector (seen);
-  release_tree_vector (todo);
+  /* Because we create class bindings lazily, we might be missing a
+     class binding for NAME.  If there are any class binding levels
+     between the LAST_BINDING_LEVEL and the scope in which OUTER was
+     declared, we must lookup NAME in those class scopes.  */
+  if (class_p)
+    while (scope && scope != outer_scope && scope->kind != sk_namespace)
+      {
+	if (scope->kind == sk_class)
+	  {
+	    cxx_binding *class_binding;
 
-  return ret;
+	    class_binding = get_class_binding (name, scope);
+	    if (class_binding)
+	      {
+		/* Thread this new class-scope binding onto the
+		   IDENTIFIER_BINDING list so that future lookups
+		   find it quickly.  */
+		class_binding->previous = outer;
+		if (binding)
+		  binding->previous = class_binding;
+		else
+		  IDENTIFIER_BINDING (name) = class_binding;
+		return class_binding;
+	      }
+	  }
+	/* If we are in a member template, the template parms of the member
+	   template are considered to be inside the scope of the containing
+	   class, but within G++ the class bindings are all pushed between the
+	   template parms and the function body.  So if the outer binding is
+	   a template parm for the current scope, return it now rather than
+	   look for a class binding.  */
+	if (outer_scope && outer_scope->kind == sk_template_parms
+	    && binding_to_template_parms_of_scope_p (outer, scope))
+	  return outer;
+
+	scope = scope->level_chain;
+      }
+
+  return outer;
 }
 
-/* Add functions of a namespace to the lookup structure.
-   Returns true on error.  */
+/* Return the innermost block-scope or class-scope value binding for
+   NAME, or NULL_TREE if there is no such binding.  */
 
-static bool
-arg_assoc_namespace (struct arg_lookup *k, tree scope)
+tree
+innermost_non_namespace_value (tree name)
 {
-  tree value;
+  cxx_binding *binding;
+  binding = outer_binding (name, /*binding=*/NULL, /*class_p=*/true);
+  return binding ? binding->value : NULL_TREE;
+}
 
-  if (vec_member (scope, k->namespaces))
-    return false;
-  vec_safe_push (k->namespaces, scope);
+/* Look up NAME in the current binding level and its superiors in the
+   namespace of variables, functions and typedefs.  Return a ..._DECL
+   node of some kind representing its definition if there is only one
+   such declaration, or return a TREE_LIST with all the overloaded
+   definitions if there are many, or return 0 if it is undefined.
+   Hidden name, either friend declaration or built-in function, are
+   not ignored.
 
-  /* Check out our super-users.  */
-  for (value = DECL_NAMESPACE_ASSOCIATIONS (scope); value;
-       value = TREE_CHAIN (value))
-    if (arg_assoc_namespace (k, TREE_PURPOSE (value)))
-      return true;
+   If PREFER_TYPE is > 0, we prefer TYPE_DECLs or namespaces.
+   If PREFER_TYPE is > 1, we reject non-type decls (e.g. namespaces).
+   Otherwise we prefer non-TYPE_DECLs.
 
-  /* Also look down into inline namespaces.  */
-  for (value = DECL_NAMESPACE_USING (scope); value;
-       value = TREE_CHAIN (value))
-    if (is_associated_namespace (scope, TREE_PURPOSE (value)))
-      if (arg_assoc_namespace (k, TREE_PURPOSE (value)))
-	return true;
+   If NONCLASS is nonzero, bindings in class scopes are ignored.  If
+   BLOCK_P is false, bindings in block scopes are ignored.  */
 
-  value = namespace_binding (k->name, scope);
-  if (!value)
-    return false;
+static tree
+lookup_name_real_1 (tree name, int prefer_type, int nonclass, bool block_p,
+		    int namespaces_only, int flags)
+{
+  cxx_binding *iter;
+  tree val = NULL_TREE;
 
-  for (; value; value = OVL_NEXT (value))
+  query_oracle (name);
+
+  /* Conversion operators are handled specially because ordinary
+     unqualified name lookup will not find template conversion
+     operators.  */
+  if (IDENTIFIER_TYPENAME_P (name))
     {
-      /* We don't want to find arbitrary hidden functions via argument
-	 dependent lookup.  We only want to find friends of associated
-	 classes, which we'll do via arg_assoc_class.  */
-      if (hidden_name_p (OVL_CURRENT (value)))
-	continue;
+      cp_binding_level *level;
 
-      if (add_function (k, OVL_CURRENT (value)))
-	return true;
+      for (level = current_binding_level;
+	   level && level->kind != sk_namespace;
+	   level = level->level_chain)
+	{
+	  tree class_type;
+	  tree operators;
+
+	  /* A conversion operator can only be declared in a class
+	     scope.  */
+	  if (level->kind != sk_class)
+	    continue;
+
+	  /* Lookup the conversion operator in the class.  */
+	  class_type = level->this_entity;
+	  operators = lookup_fnfields (class_type, name, /*protect=*/0);
+	  if (operators)
+	    return operators;
+	}
+
+      return NULL_TREE;
     }
 
-  return false;
-}
+  flags |= lookup_flags (prefer_type, namespaces_only);
+
+  /* First, look in non-namespace scopes.  */
+
+  if (current_class_type == NULL_TREE)
+    nonclass = 1;
 
-/* Adds everything associated with a template argument to the lookup
-   structure.  Returns true on error.  */
+  if (block_p || !nonclass)
+    for (iter = outer_binding (name, NULL, !nonclass);
+	 iter;
+	 iter = outer_binding (name, iter, !nonclass))
+      {
+	tree binding;
 
-static bool
-arg_assoc_template_arg (struct arg_lookup *k, tree arg)
-{
-  /* [basic.lookup.koenig]
+	/* Skip entities we don't want.  */
+	if (LOCAL_BINDING_P (iter) ? !block_p : nonclass)
+	  continue;
 
-     If T is a template-id, its associated namespaces and classes are
-     ... the namespaces and classes associated with the types of the
-     template arguments provided for template type parameters
-     (excluding template template parameters); the namespaces in which
-     any template template arguments are defined; and the classes in
-     which any member templates used as template template arguments
-     are defined.  [Note: non-type template arguments do not
-     contribute to the set of associated namespaces.  ]  */
+	/* If this is the kind of thing we're looking for, we're done.  */
+	if (qualify_lookup (iter->value, flags))
+	  binding = iter->value;
+	else if ((flags & LOOKUP_PREFER_TYPES)
+		 && qualify_lookup (iter->type, flags))
+	  binding = iter->type;
+	else
+	  binding = NULL_TREE;
 
-  /* Consider first template template arguments.  */
-  if (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
-      || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE)
-    return false;
-  else if (TREE_CODE (arg) == TEMPLATE_DECL)
-    {
-      tree ctx = CP_DECL_CONTEXT (arg);
+	if (binding)
+	  {
+	    if (hidden_name_p (binding))
+	      {
+		/* A non namespace-scope binding can only be hidden in the
+		   presence of a local class, due to friend declarations.
 
-      /* It's not a member template.  */
-      if (TREE_CODE (ctx) == NAMESPACE_DECL)
-	return arg_assoc_namespace (k, ctx);
-      /* Otherwise, it must be member template.  */
-      else
-	return arg_assoc_class_only (k, ctx);
-    }
-  /* It's an argument pack; handle it recursively.  */
-  else if (ARGUMENT_PACK_P (arg))
-    {
-      tree args = ARGUMENT_PACK_ARGS (arg);
-      int i, len = TREE_VEC_LENGTH (args);
-      for (i = 0; i < len; ++i) 
-	if (arg_assoc_template_arg (k, TREE_VEC_ELT (args, i)))
-	  return true;
+		   In particular, consider:
 
-      return false;
-    }
-  /* It's not a template template argument, but it is a type template
-     argument.  */
-  else if (TYPE_P (arg))
-    return arg_assoc_type (k, arg);
-  /* It's a non-type template argument.  */
-  else
-    return false;
-}
+		   struct C;
+		   void f() {
+		     struct A {
+		       friend struct B;
+		       friend struct C;
+		       void g() {
+		         B* b; // error: B is hidden
+			 C* c; // OK, finds ::C
+		       } 
+		     };
+		     B *b;  // error: B is hidden
+		     C *c;  // OK, finds ::C
+		     struct B {};
+		     B *bb; // OK
+		   }
 
-/* Adds the class and its friends to the lookup structure.
-   Returns true on error.  */
+		   The standard says that "B" is a local class in "f"
+		   (but not nested within "A") -- but that name lookup
+		   for "B" does not find this declaration until it is
+		   declared directly with "f".
 
-static bool
-arg_assoc_class_only (struct arg_lookup *k, tree type)
-{
-  tree list, friends, context;
+		   In particular:
 
-  /* Backend-built structures, such as __builtin_va_list, aren't
-     affected by all this.  */
-  if (!CLASS_TYPE_P (type))
-    return false;
+		   [class.friend]
 
-  context = decl_namespace_context (type);
-  if (arg_assoc_namespace (k, context))
-    return true;
+		   If a friend declaration appears in a local class and
+		   the name specified is an unqualified name, a prior
+		   declaration is looked up without considering scopes
+		   that are outside the innermost enclosing non-class
+		   scope. For a friend function declaration, if there is
+		   no prior declaration, the program is ill-formed. For a
+		   friend class declaration, if there is no prior
+		   declaration, the class that is specified belongs to the
+		   innermost enclosing non-class scope, but if it is
+		   subsequently referenced, its name is not found by name
+		   lookup until a matching declaration is provided in the
+		   innermost enclosing nonclass scope.
 
-  complete_type (type);
+		   So just keep looking for a non-hidden binding.
+		*/
+		gcc_assert (TREE_CODE (binding) == TYPE_DECL);
+		continue;
+	      }
+	    val = binding;
+	    break;
+	  }
+      }
 
-  /* Process friends.  */
-  for (list = DECL_FRIENDLIST (TYPE_MAIN_DECL (type)); list;
-       list = TREE_CHAIN (list))
-    if (k->name == FRIEND_NAME (list))
-      for (friends = FRIEND_DECLS (list); friends;
-	   friends = TREE_CHAIN (friends))
-	{
-	  tree fn = TREE_VALUE (friends);
+  /* Now lookup in namespace scopes.  */
+  if (!val)
+    val = unqualified_namespace_lookup (name, flags);
 
-	  /* Only interested in global functions with potentially hidden
-	     (i.e. unqualified) declarations.  */
-	  if (CP_DECL_CONTEXT (fn) != context)
-	    continue;
-	  /* Template specializations are never found by name lookup.
-	     (Templates themselves can be found, but not template
-	     specializations.)  */
-	  if (TREE_CODE (fn) == FUNCTION_DECL && DECL_USE_TEMPLATE (fn))
-	    continue;
-	  if (add_function (k, fn))
-	    return true;
-	}
+  /* Anticipated built-ins and friends aren't found by normal lookup.  */
+  if (val && !(flags & LOOKUP_HIDDEN))
+    val = remove_hidden_names (val);
 
-  return false;
+  /* If we have a single function from a using decl, pull it out.  */
+  if (val && TREE_CODE (val) == OVERLOAD && !really_overloaded_fn (val))
+    val = OVL_FUNCTION (val);
+
+  return val;
 }
 
-/* Adds the class and its bases to the lookup structure.
-   Returns true on error.  */
+/* Wrapper for lookup_name_real_1.  */
 
-static bool
-arg_assoc_bases (struct arg_lookup *k, tree type)
+tree
+lookup_name_real (tree name, int prefer_type, int nonclass, bool block_p,
+		  int namespaces_only, int flags)
 {
-  if (arg_assoc_class_only (k, type))
-    return true;
-
-  if (TYPE_BINFO (type))
-    {
-      /* Process baseclasses.  */
-      tree binfo, base_binfo;
-      int i;
-
-      for (binfo = TYPE_BINFO (type), i = 0;
-	   BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
-	if (arg_assoc_bases (k, BINFO_TYPE (base_binfo)))
-	  return true;
-    }
+  tree ret;
+  bool subtime = timevar_cond_start (TV_NAME_LOOKUP);
+  ret = lookup_name_real_1 (name, prefer_type, nonclass, block_p,
+			    namespaces_only, flags);
+  timevar_cond_stop (TV_NAME_LOOKUP, subtime);
+  return ret;
+}
 
-  return false;
+tree
+lookup_name_nonclass (tree name)
+{
+  return lookup_name_real (name, 0, 1, /*block_p=*/true, 0, 0);
 }
 
-/* Adds everything associated with a class argument type to the lookup
-   structure.  Returns true on error.
+tree
+lookup_function_nonclass (tree name, vec<tree, va_gc> *args, bool block_p)
+{
+  return
+    lookup_arg_dependent (name,
+			  lookup_name_real (name, 0, 1, block_p, 0, 0),
+			  args);
+}
 
-   If T is a class type (including unions), its associated classes are: the
-   class itself; the class of which it is a member, if any; and its direct
-   and indirect base classes. Its associated namespaces are the namespaces
-   of which its associated classes are members. Furthermore, if T is a
-   class template specialization, its associated namespaces and classes
-   also include: the namespaces and classes associated with the types of
-   the template arguments provided for template type parameters (excluding
-   template template parameters); the namespaces of which any template
-   template arguments are members; and the classes of which any member
-   templates used as template template arguments are members. [ Note:
-   non-type template arguments do not contribute to the set of associated
-   namespaces.  --end note] */
+tree
+lookup_name (tree name)
+{
+  return lookup_name_real (name, 0, 0, /*block_p=*/true, 0, 0);
+}
 
-static bool
-arg_assoc_class (struct arg_lookup *k, tree type)
+tree
+lookup_name_prefer_type (tree name, int prefer_type)
 {
-  tree list;
-  int i;
+  return lookup_name_real (name, prefer_type, 0, /*block_p=*/true, 0, 0);
+}
 
-  /* Backend build structures, such as __builtin_va_list, aren't
-     affected by all this.  */
-  if (!CLASS_TYPE_P (type))
-    return false;
+/* Look up NAME for type used in elaborated name specifier in
+   the scopes given by SCOPE.  SCOPE can be either TS_CURRENT or
+   TS_WITHIN_ENCLOSING_NON_CLASS.  Although not implied by the
+   name, more scopes are checked if cleanup or template parameter
+   scope is encountered.
 
-  if (vec_member (type, k->classes))
-    return false;
-  vec_safe_push (k->classes, type);
+   Unlike lookup_name_real, we make sure that NAME is actually
+   declared in the desired scope, not from inheritance, nor using
+   directive.  For using declaration, there is DR138 still waiting
+   to be resolved.  Hidden name coming from an earlier friend
+   declaration is also returned.
 
-  if (TYPE_CLASS_SCOPE_P (type)
-      && arg_assoc_class_only (k, TYPE_CONTEXT (type)))
-    return true;
+   A TYPE_DECL best matching the NAME is returned.  Catching error
+   and issuing diagnostics are caller's responsibility.  */
 
-  if (arg_assoc_bases (k, type))
-    return true;
+static tree
+lookup_type_scope_1 (tree name, tag_scope scope)
+{
+  cxx_binding *iter = NULL;
+  tree val = NULL_TREE;
 
-  /* Process template arguments.  */
-  if (CLASSTYPE_TEMPLATE_INFO (type)
-      && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (type)))
+  /* Look in non-namespace scope first.  */
+  if (current_binding_level->kind != sk_namespace)
+    iter = outer_binding (name, NULL, /*class_p=*/ true);
+  for (; iter; iter = outer_binding (name, iter, /*class_p=*/ true))
     {
-      list = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type));
-      for (i = 0; i < TREE_VEC_LENGTH (list); ++i)
-	if (arg_assoc_template_arg (k, TREE_VEC_ELT (list, i)))
-	  return true;
-    }
+      /* Check if this is the kind of thing we're looking for.
+	 If SCOPE is TS_CURRENT, also make sure it doesn't come from
+	 base class.  For ITER->VALUE, we can simply use
+	 INHERITED_VALUE_BINDING_P.  For ITER->TYPE, we have to use
+	 our own check.
 
-  return false;
-}
+	 We check ITER->TYPE before ITER->VALUE in order to handle
+	   typedef struct C {} C;
+	 correctly.  */
 
-/* Adds everything associated with a given type.
-   Returns 1 on error.  */
+      if (qualify_lookup (iter->type, LOOKUP_PREFER_TYPES)
+	  && (scope != ts_current
+	      || LOCAL_BINDING_P (iter)
+	      || DECL_CONTEXT (iter->type) == iter->scope->this_entity))
+	val = iter->type;
+      else if ((scope != ts_current
+		|| !INHERITED_VALUE_BINDING_P (iter))
+	       && qualify_lookup (iter->value, LOOKUP_PREFER_TYPES))
+	val = iter->value;
 
-static bool
-arg_assoc_type (struct arg_lookup *k, tree type)
-{
-  /* As we do not get the type of non-type dependent expressions
-     right, we can end up with such things without a type.  */
-  if (!type)
-    return false;
+      if (val)
+	break;
+    }
 
-  if (TYPE_PTRDATAMEM_P (type))
+  /* Look in namespace scope.  */
+  if (!val)
     {
-      /* Pointer to member: associate class type and value type.  */
-      if (arg_assoc_type (k, TYPE_PTRMEM_CLASS_TYPE (type)))
-	return true;
-      return arg_assoc_type (k, TYPE_PTRMEM_POINTED_TO_TYPE (type));
+      iter = cp_binding_level_find_binding_for_name
+	       (NAMESPACE_LEVEL (current_decl_namespace ()), name);
+
+      if (iter)
+	{
+	  /* If this is the kind of thing we're looking for, we're done.  */
+	  if (qualify_lookup (iter->type, LOOKUP_PREFER_TYPES))
+	    val = iter->type;
+	  else if (qualify_lookup (iter->value, LOOKUP_PREFER_TYPES))
+	    val = iter->value;
+	}
+
     }
-  else switch (TREE_CODE (type))
+
+  /* Type found, check if it is in the allowed scopes, ignoring cleanup
+     and template parameter scopes.  */
+  if (val)
     {
-    case ERROR_MARK:
-      return false;
-    case VOID_TYPE:
-    case INTEGER_TYPE:
-    case REAL_TYPE:
-    case COMPLEX_TYPE:
-    case VECTOR_TYPE:
-    case BOOLEAN_TYPE:
-    case FIXED_POINT_TYPE:
-    case DECLTYPE_TYPE:
-    case NULLPTR_TYPE:
-      return false;
-    case RECORD_TYPE:
-      if (TYPE_PTRMEMFUNC_P (type))
-	return arg_assoc_type (k, TYPE_PTRMEMFUNC_FN_TYPE (type));
-      /* FALLTHRU */
-    case UNION_TYPE:
-      return arg_assoc_class (k, type);
-    case POINTER_TYPE:
-    case REFERENCE_TYPE:
-    case ARRAY_TYPE:
-      return arg_assoc_type (k, TREE_TYPE (type));
-    case ENUMERAL_TYPE:
-      if (TYPE_CLASS_SCOPE_P (type)
-	  && arg_assoc_class_only (k, TYPE_CONTEXT (type)))
-	return true;
-      return arg_assoc_namespace (k, decl_namespace_context (type));
-    case METHOD_TYPE:
-      /* The basetype is referenced in the first arg type, so just
-	 fall through.  */
-    case FUNCTION_TYPE:
-      /* Associate the parameter types.  */
-      if (arg_assoc_args (k, TYPE_ARG_TYPES (type)))
-	return true;
-      /* Associate the return type.  */
-      return arg_assoc_type (k, TREE_TYPE (type));
-    case TEMPLATE_TYPE_PARM:
-    case BOUND_TEMPLATE_TEMPLATE_PARM:
-      return false;
-    case TYPENAME_TYPE:
-      return false;
-    case LANG_TYPE:
-      gcc_assert (type == unknown_type_node
-		  || type == init_list_type_node);
-      return false;
-    case TYPE_PACK_EXPANSION:
-      return arg_assoc_type (k, PACK_EXPANSION_PATTERN (type));
+      cp_binding_level *b = current_binding_level;
+      while (b)
+	{
+	  if (iter->scope == b)
+	    return val;
 
-    default:
-      gcc_unreachable ();
+	  if (b->kind == sk_cleanup || b->kind == sk_template_parms
+	      || b->kind == sk_function_parms)
+	    b = b->level_chain;
+	  else if (b->kind == sk_class
+		   && scope == ts_within_enclosing_non_class)
+	    b = b->level_chain;
+	  else
+	    break;
+	}
     }
-  return false;
-}
 
-/* Adds everything associated with arguments.  Returns true on error.  */
-
-static bool
-arg_assoc_args (struct arg_lookup *k, tree args)
-{
-  for (; args; args = TREE_CHAIN (args))
-    if (arg_assoc (k, TREE_VALUE (args)))
-      return true;
-  return false;
+  return NULL_TREE;
 }
+ 
+/* Wrapper for lookup_type_scope_1.  */
 
-/* Adds everything associated with an argument vector.  Returns true
-   on error.  */
-
-static bool
-arg_assoc_args_vec (struct arg_lookup *k, vec<tree, va_gc> *args)
+tree
+lookup_type_scope (tree name, tag_scope scope)
 {
-  unsigned int ix;
-  tree arg;
-
-  FOR_EACH_VEC_SAFE_ELT (args, ix, arg)
-    if (arg_assoc (k, arg))
-      return true;
-  return false;
+  tree ret;
+  bool subtime = timevar_cond_start (TV_NAME_LOOKUP);
+  ret = lookup_type_scope_1 (name, scope);
+  timevar_cond_stop (TV_NAME_LOOKUP, subtime);
+  return ret;
 }
 
-/* Adds everything associated with a given tree_node.  Returns 1 on error.  */
-
-static bool
-arg_assoc (struct arg_lookup *k, tree n)
-{
-  if (n == error_mark_node)
-    return false;
 
-  if (TYPE_P (n))
-    return arg_assoc_type (k, n);
+/* Similar to `lookup_name' but look only in the innermost non-class
+   binding level.  */
 
-  if (! type_unknown_p (n))
-    return arg_assoc_type (k, TREE_TYPE (n));
+static tree
+lookup_name_innermost_nonclass_level_1 (tree name)
+{
+  cp_binding_level *b;
+  tree t = NULL_TREE;
 
-  if (TREE_CODE (n) == ADDR_EXPR)
-    n = TREE_OPERAND (n, 0);
-  if (TREE_CODE (n) == COMPONENT_REF)
-    n = TREE_OPERAND (n, 1);
-  if (TREE_CODE (n) == OFFSET_REF)
-    n = TREE_OPERAND (n, 1);
-  while (TREE_CODE (n) == TREE_LIST)
-    n = TREE_VALUE (n);
-  if (BASELINK_P (n))
-    n = BASELINK_FUNCTIONS (n);
+  b = innermost_nonclass_level ();
 
-  if (TREE_CODE (n) == FUNCTION_DECL)
-    return arg_assoc_type (k, TREE_TYPE (n));
-  if (TREE_CODE (n) == TEMPLATE_ID_EXPR)
+  if (b->kind == sk_namespace)
     {
-      /* The working paper doesn't currently say how to handle template-id
-	 arguments.  The sensible thing would seem to be to handle the list
-	 of template candidates like a normal overload set, and handle the
-	 template arguments like we do for class template
-	 specializations.  */
-      tree templ = TREE_OPERAND (n, 0);
-      tree args = TREE_OPERAND (n, 1);
-      int ix;
-
-      /* First the templates.  */
-      if (arg_assoc (k, templ))
-	return true;
+      t = IDENTIFIER_NAMESPACE_VALUE (name);
 
-      /* Now the arguments.  */
-      if (args)
-	for (ix = TREE_VEC_LENGTH (args); ix--;)
-	  if (arg_assoc_template_arg (k, TREE_VEC_ELT (args, ix)) == 1)
-	    return true;
+      /* extern "C" function() */
+      if (t != NULL_TREE && TREE_CODE (t) == TREE_LIST)
+	t = TREE_VALUE (t);
     }
-  else if (TREE_CODE (n) == OVERLOAD)
+  else if (IDENTIFIER_BINDING (name)
+	   && LOCAL_BINDING_P (IDENTIFIER_BINDING (name)))
     {
-      for (; n; n = OVL_NEXT (n))
-	if (arg_assoc_type (k, TREE_TYPE (OVL_CURRENT (n))))
-	  return true;
+      cxx_binding *binding;
+      binding = IDENTIFIER_BINDING (name);
+      while (1)
+	{
+	  if (binding->scope == b
+	      && !(VAR_P (binding->value)
+		   && DECL_DEAD_FOR_LOCAL (binding->value)))
+	    return binding->value;
+
+	  if (b->kind == sk_cleanup)
+	    b = b->level_chain;
+	  else
+	    break;
+	}
     }
 
-  return false;
+  return t;
+}
+
+/* Wrapper for lookup_name_innermost_nonclass_level_1.  */
+
+tree
+lookup_name_innermost_nonclass_level (tree name)
+{
+  tree ret;
+  bool subtime = timevar_cond_start (TV_NAME_LOOKUP);
+  ret = lookup_name_innermost_nonclass_level_1 (name);
+  timevar_cond_stop (TV_NAME_LOOKUP, subtime);
+  return ret;
 }
 
-/* Performs Koenig lookup depending on arguments, where fns
-   are the functions found in normal lookup.  */
 
-static cp_expr
-lookup_arg_dependent_1 (tree name, tree fns, vec<tree, va_gc> *args)
+/* Returns true iff DECL is a block-scope extern declaration of a function
+   or variable.  */
+
+bool
+is_local_extern (tree decl)
 {
-  struct arg_lookup k;
+  cxx_binding *binding;
 
-  /* Remove any hidden friend functions from the list of functions
-     found so far.  They will be added back by arg_assoc_class as
-     appropriate.  */
-  fns = remove_hidden_names (fns);
+  /* For functions, this is easy.  */
+  if (TREE_CODE (decl) == FUNCTION_DECL)
+    return DECL_LOCAL_FUNCTION_P (decl);
 
-  k.name = name;
-  k.args = args;
-  k.functions = fns;
-  k.classes = make_tree_vector ();
+  if (!VAR_P (decl))
+    return false;
+  if (!current_function_decl)
+    return false;
 
-  /* We previously performed an optimization here by setting
-     NAMESPACES to the current namespace when it was safe. However, DR
-     164 says that namespaces that were already searched in the first
-     stage of template processing are searched again (potentially
-     picking up later definitions) in the second stage. */
-  k.namespaces = make_tree_vector ();
+  /* For variables, this is not easy.  We need to look at the binding stack
+     for the identifier to see whether the decl we have is a local.  */
+  for (binding = IDENTIFIER_BINDING (DECL_NAME (decl));
+       binding && binding->scope->kind != sk_namespace;
+       binding = binding->previous)
+    if (binding->value == decl)
+      return LOCAL_BINDING_P (binding);
 
-  /* We used to allow duplicates and let joust discard them, but
-     since the above change for DR 164 we end up with duplicates of
-     all the functions found by unqualified lookup.  So keep track
-     of which ones we've seen.  */
-  if (fns)
-    {
-      tree ovl;
-      /* We shouldn't be here if lookup found something other than
-	 namespace-scope functions.  */
-      gcc_assert (DECL_NAMESPACE_SCOPE_P (OVL_CURRENT (fns)));
-      k.fn_set = new hash_set<tree>;
-      for (ovl = fns; ovl; ovl = OVL_NEXT (ovl))
-	k.fn_set->add (OVL_CURRENT (ovl));
-    }
-  else
-    k.fn_set = NULL;
+  return false;
+}
 
-  arg_assoc_args_vec (&k, args);
+/* Like lookup_name_innermost_nonclass_level, but for types.  */
 
-  fns = k.functions;
-  
-  if (fns
-      && !VAR_P (fns)
-      && !is_overloaded_fn (fns))
-    {
-      error ("argument dependent lookup finds %q+D", fns);
-      error ("  in call to %qD", name);
-      fns = error_mark_node;
-    }
+static tree
+lookup_type_current_level (tree name)
+{
+  tree t = NULL_TREE;
 
-  release_tree_vector (k.classes);
-  release_tree_vector (k.namespaces);
-  delete k.fn_set;
-    
-  return fns;
-}
+  timevar_start (TV_NAME_LOOKUP);
+  gcc_assert (current_binding_level->kind != sk_namespace);
 
-/* Wrapper for lookup_arg_dependent_1.  */
+  if (REAL_IDENTIFIER_TYPE_VALUE (name) != NULL_TREE
+      && REAL_IDENTIFIER_TYPE_VALUE (name) != global_type_node)
+    {
+      cp_binding_level *b = current_binding_level;
+      while (1)
+	{
+	  if (purpose_member (name, b->type_shadowed))
+	    {
+	      t = REAL_IDENTIFIER_TYPE_VALUE (name);
+	      break;
+	    }
+	  if (b->kind == sk_cleanup)
+	    b = b->level_chain;
+	  else
+	    break;
+	}
+    }
 
-cp_expr
-lookup_arg_dependent (tree name, tree fns, vec<tree, va_gc> *args)
-{
-  cp_expr ret;
-  bool subtime;
-  subtime = timevar_cond_start (TV_NAME_LOOKUP);
-  ret = lookup_arg_dependent_1 (name, fns, args);
-  timevar_cond_stop (TV_NAME_LOOKUP, subtime);
-  return ret;
+  timevar_stop (TV_NAME_LOOKUP);
+  return t;
 }
 
-
 /* Add namespace to using_directives. Return NULL_TREE if nothing was
    changed (i.e. there was already a directive), or the fresh
    TREE_LIST otherwise.  */
@@ -6618,6 +6472,152 @@ pop_from_top_level (void)
   timevar_cond_stop (TV_NAME_LOOKUP, subtime);
 }
 
+/* Push into the scope of the NAME namespace.  If NAME is NULL_TREE, then we
+   select a name that is unique to this compilation unit.  Returns FALSE if
+   pushdecl fails, TRUE otherwise.  */
+
+bool
+push_namespace (tree name)
+{
+  tree d = NULL_TREE;
+  bool need_new = true;
+  bool implicit_use = false;
+  bool anon = !name;
+
+  bool subtime = timevar_cond_start (TV_NAME_LOOKUP);
+
+  /* We should not get here if the global_namespace is not yet constructed
+     nor if NAME designates the global namespace:  The global scope is
+     constructed elsewhere.  */
+  gcc_assert (global_namespace != NULL && name != global_scope_name);
+
+  if (anon)
+    {
+      name = get_anonymous_namespace_name();
+      d = IDENTIFIER_NAMESPACE_VALUE (name);
+      if (d)
+	/* Reopening anonymous namespace.  */
+	need_new = false;
+      implicit_use = true;
+    }
+  else
+    {
+      /* Check whether this is an extended namespace definition.  */
+      d = IDENTIFIER_NAMESPACE_VALUE (name);
+      if (d != NULL_TREE && TREE_CODE (d) == NAMESPACE_DECL)
+	{
+	  tree dna = DECL_NAMESPACE_ALIAS (d);
+	  if (dna)
+ 	    {
+	      /* We do some error recovery for, eg, the redeclaration
+		 of M here:
+
+		 namespace N {}
+		 namespace M = N;
+		 namespace M {}
+
+		 However, in nasty cases like:
+
+		 namespace N
+		 {
+		   namespace M = N;
+		   namespace M {}
+		 }
+
+		 we just error out below, in duplicate_decls.  */
+	      if (NAMESPACE_LEVEL (dna)->level_chain
+		  == current_binding_level)
+		{
+		  error ("namespace alias %qD not allowed here, "
+			 "assuming %qD", d, dna);
+		  d = dna;
+		  need_new = false;
+		}
+	    }
+	  else
+	    need_new = false;
+	}
+    }
+
+  if (need_new)
+    {
+      /* Make a new namespace, binding the name to it.  */
+      d = build_lang_decl (NAMESPACE_DECL, name, void_type_node);
+      DECL_CONTEXT (d) = FROB_CONTEXT (current_namespace);
+      /* The name of this namespace is not visible to other translation
+	 units if it is an anonymous namespace or member thereof.  */
+      if (anon || decl_anon_ns_mem_p (current_namespace))
+	TREE_PUBLIC (d) = 0;
+      else
+	TREE_PUBLIC (d) = 1;
+      if (pushdecl (d) == error_mark_node)
+	{
+	  timevar_cond_stop (TV_NAME_LOOKUP, subtime);
+	  return false;
+	}
+      if (anon)
+	{
+	  /* Clear DECL_NAME for the benefit of debugging back ends.  */
+	  SET_DECL_ASSEMBLER_NAME (d, name);
+	  DECL_NAME (d) = NULL_TREE;
+	}
+      begin_scope (sk_namespace, d);
+    }
+  else
+    resume_scope (NAMESPACE_LEVEL (d));
+
+  if (implicit_use)
+    do_using_directive (d);
+  /* Enter the name space.  */
+  current_namespace = d;
+
+  timevar_cond_stop (TV_NAME_LOOKUP, subtime);
+  return true;
+}
+
+/* Pop from the scope of the current namespace.  */
+
+void
+pop_namespace (void)
+{
+  gcc_assert (current_namespace != global_namespace);
+  current_namespace = CP_DECL_CONTEXT (current_namespace);
+  /* The binding level is not popped, as it might be re-opened later.  */
+  leave_scope ();
+}
+
+/* Push into the scope of the namespace NS, even if it is deeply
+   nested within another namespace.  */
+
+void
+push_nested_namespace (tree ns)
+{
+  if (ns == global_namespace)
+    push_to_top_level ();
+  else
+    {
+      push_nested_namespace (CP_DECL_CONTEXT (ns));
+      push_namespace (DECL_NAME (ns));
+    }
+}
+
+/* Pop back from the scope of the namespace NS, which was previously
+   entered with push_nested_namespace.  */
+
+void
+pop_nested_namespace (tree ns)
+{
+  bool subtime = timevar_cond_start (TV_NAME_LOOKUP);
+  gcc_assert (current_namespace == ns);
+  while (ns != global_namespace)
+    {
+      pop_namespace ();
+      ns = CP_DECL_CONTEXT (ns);
+    }
+
+  pop_from_top_level ();
+  timevar_cond_stop (TV_NAME_LOOKUP, subtime);
+}
 
 /* Pop off extraneous binding levels left over due to syntax errors.
 
