90th Cygnus<->FSF quick merge

From-SVN: r13831

1 files changed, 414 insertions, 0 deletions

diff --git a/gcc/cp/friend.c b/gcc/cp/friend.c
new file mode 100644
index 0000000..6d7d9d5
--- /dev/null
+++ b/gcc/cp/friend.c
@@ -0,0 +1,414 @@
+/* Help friends in C++.
+   Copyright (C) 1997 Free Software Foundation, Inc.
+
+This file is part of GNU CC.
+
+GNU CC is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2, or (at your option)
+any later version.
+
+GNU CC is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with GNU CC; see the file COPYING.  If not, write to
+the Free Software Foundation, 59 Temple Place - Suite 330,
+Boston, MA 02111-1307, USA.  */
+
+#include "config.h"
+#include "tree.h"
+#include "rtl.h"
+#include "cp-tree.h"
+#include "flags.h"
+#include "output.h"
+
+/* Friend data structures:
+
+   Lists of friend functions come from TYPE_DECL nodes.  Since all
+   aggregate types are automatically typedef'd, these nodes are guaranteed
+   to exist.
+
+   The TREE_PURPOSE of a friend list is the name of the friend,
+   and its TREE_VALUE is another list.
+
+   For each element of that list, either the TREE_VALUE or the TREE_PURPOSE
+   will be filled in, but not both.  The TREE_VALUE of that list is an
+   individual function which is a friend.  The TREE_PURPOSE of that list
+   indicates a type in which all functions by that name are friends.
+
+   Lists of friend classes come from _TYPE nodes.  Love that consistency
+   thang.  */
+
+int
+is_friend (type, supplicant)
+     tree type, supplicant;
+{
+  int declp;
+  register tree list;
+
+  if (supplicant == NULL_TREE || type == NULL_TREE)
+    return 0;
+
+  declp = (TREE_CODE_CLASS (TREE_CODE (supplicant)) == 'd');
+
+  if (declp)
+    /* It's a function decl.  */
+    {
+      tree list = DECL_FRIENDLIST (TYPE_MAIN_DECL (type));
+      tree name = DECL_NAME (supplicant);
+      tree ctype;
+
+      if (DECL_FUNCTION_MEMBER_P (supplicant))
+	ctype = DECL_CLASS_CONTEXT (supplicant);
+      else
+	ctype = NULL_TREE;
+
+      for (; list ; list = TREE_CHAIN (list))
+	{
+	  if (name == TREE_PURPOSE (list))
+	    {
+	      tree friends = TREE_VALUE (list);
+	      for (; friends ; friends = TREE_CHAIN (friends))
+		{
+		  if (ctype == TREE_PURPOSE (friends))
+		    return 1;
+		  if (comptypes (TREE_TYPE (supplicant),
+				 TREE_TYPE (TREE_VALUE (friends)), 1))
+		    return 1;
+		}
+	      break;
+	    }
+	}
+    }
+  else
+    /* It's a type.  */
+    {
+      if (type == supplicant)
+	return 1;
+      
+      list = CLASSTYPE_FRIEND_CLASSES (TREE_TYPE (TYPE_MAIN_DECL (type)));
+      for (; list ; list = TREE_CHAIN (list))
+	if (supplicant == TREE_VALUE (list))
+	  return 1;
+    }      
+
+  {
+    tree context;
+
+    if (! declp)
+      {
+	/* Are we a nested or local class?  If so, we aren't friends
+           with the CONTEXT.  */
+	if (IS_AGGR_TYPE (supplicant))
+	  context = NULL_TREE;
+	else
+	  context = DECL_CONTEXT (TYPE_MAIN_DECL (supplicant));
+      }
+    else if (DECL_FUNCTION_MEMBER_P (supplicant))
+      context = DECL_CLASS_CONTEXT (supplicant);
+    else
+      context = NULL_TREE;
+
+    if (context)
+      return is_friend (type, context);
+  }
+
+  return 0;
+}
+
+/* Add a new friend to the friends of the aggregate type TYPE.
+   DECL is the FUNCTION_DECL of the friend being added.  */
+
+static void
+add_friend (type, decl)
+     tree type, decl;
+{
+  tree typedecl = TYPE_MAIN_DECL (type);
+  tree list = DECL_FRIENDLIST (typedecl);
+  tree name = DECL_NAME (decl);
+
+  while (list)
+    {
+      if (name == TREE_PURPOSE (list))
+	{
+	  tree friends = TREE_VALUE (list);
+	  for (; friends ; friends = TREE_CHAIN (friends))
+	    {
+	      if (decl == TREE_VALUE (friends))
+		{
+		  cp_warning ("`%D' is already a friend of class `%T'",
+			      decl, type);
+		  cp_warning_at ("previous friend declaration of `%D'",
+				 TREE_VALUE (friends));
+		  return;
+		}
+	    }
+	  TREE_VALUE (list) = tree_cons (error_mark_node, decl,
+					 TREE_VALUE (list));
+	  return;
+	}
+      list = TREE_CHAIN (list);
+    }
+  DECL_FRIENDLIST (typedecl)
+    = tree_cons (DECL_NAME (decl), build_tree_list (error_mark_node, decl),
+		 DECL_FRIENDLIST (typedecl));
+  if (DECL_NAME (decl) == ansi_opname[(int) MODIFY_EXPR])
+    {
+      tree parmtypes = TYPE_ARG_TYPES (TREE_TYPE (decl));
+      TYPE_HAS_ASSIGNMENT (TREE_TYPE (typedecl)) = 1;
+      if (parmtypes && TREE_CHAIN (parmtypes))
+	{
+	  tree parmtype = TREE_VALUE (TREE_CHAIN (parmtypes));
+	  if (TREE_CODE (parmtype) == REFERENCE_TYPE
+	      && TREE_TYPE (parmtypes) == TREE_TYPE (typedecl))
+	    TYPE_HAS_ASSIGN_REF (TREE_TYPE (typedecl)) = 1;
+	}
+    }
+}
+
+/* Declare that every member function NAME in FRIEND_TYPE
+   (which may be NULL_TREE) is a friend of type TYPE.  */
+
+static void
+add_friends (type, name, friend_type)
+     tree type, name, friend_type;
+{
+  tree typedecl = TYPE_MAIN_DECL (type);
+  tree list = DECL_FRIENDLIST (typedecl);
+
+  while (list)
+    {
+      if (name == TREE_PURPOSE (list))
+	{
+	  tree friends = TREE_VALUE (list);
+	  while (friends && TREE_PURPOSE (friends) != friend_type)
+	    friends = TREE_CHAIN (friends);
+	  if (friends)
+	    if (friend_type)
+	      warning ("method `%s::%s' is already a friend of class",
+		       TYPE_NAME_STRING (friend_type),
+		       IDENTIFIER_POINTER (name));
+	    else
+	      warning ("function `%s' is already a friend of class `%s'",
+		       IDENTIFIER_POINTER (name),
+		       IDENTIFIER_POINTER (DECL_NAME (typedecl)));
+	  else
+	    TREE_VALUE (list) = tree_cons (friend_type, NULL_TREE,
+					   TREE_VALUE (list));
+	  return;
+	}
+      list = TREE_CHAIN (list);
+    }
+  DECL_FRIENDLIST (typedecl) =
+    tree_cons (name,
+	       build_tree_list (friend_type, NULL_TREE),
+	       DECL_FRIENDLIST (typedecl));
+  if (! strncmp (IDENTIFIER_POINTER (name),
+		 IDENTIFIER_POINTER (ansi_opname[(int) MODIFY_EXPR]),
+		 strlen (IDENTIFIER_POINTER (ansi_opname[(int) MODIFY_EXPR]))))
+    {
+      TYPE_HAS_ASSIGNMENT (TREE_TYPE (typedecl)) = 1;
+      sorry ("declaring \"friend operator =\" will not find \"operator = (X&)\" if it exists");
+    }
+}
+
+/* Make FRIEND_TYPE a friend class to TYPE.  If FRIEND_TYPE has already
+   been defined, we make all of its member functions friends of
+   TYPE.  If not, we make it a pending friend, which can later be added
+   when its definition is seen.  If a type is defined, then its TYPE_DECL's
+   DECL_UNDEFINED_FRIENDS contains a (possibly empty) list of friend
+   classes that are not defined.  If a type has not yet been defined,
+   then the DECL_WAITING_FRIENDS contains a list of types
+   waiting to make it their friend.  Note that these two can both
+   be in use at the same time!  */
+
+void
+make_friend_class (type, friend_type)
+     tree type, friend_type;
+{
+  tree classes;
+
+  if (IS_SIGNATURE (type))
+    {
+      error ("`friend' declaration in signature definition");
+      return;
+    }
+  if (IS_SIGNATURE (friend_type))
+    {
+      error ("signature type `%s' declared `friend'",
+	     IDENTIFIER_POINTER (TYPE_IDENTIFIER (friend_type)));
+      return;
+    }
+  if (type == friend_type)
+    {
+      pedwarn ("class `%s' is implicitly friends with itself",
+	       TYPE_NAME_STRING (type));
+      return;
+    }
+
+  GNU_xref_hier (TYPE_NAME_STRING (type),
+		 TYPE_NAME_STRING (friend_type), 0, 0, 1);
+
+  classes = CLASSTYPE_FRIEND_CLASSES (type);
+  while (classes && TREE_VALUE (classes) != friend_type)
+    classes = TREE_CHAIN (classes);
+  if (classes)
+    warning ("class `%s' is already friends with class `%s'",
+	     TYPE_NAME_STRING (TREE_VALUE (classes)), TYPE_NAME_STRING (type));
+  else
+    {
+      CLASSTYPE_FRIEND_CLASSES (type)
+	= tree_cons (NULL_TREE, friend_type, CLASSTYPE_FRIEND_CLASSES (type));
+    }
+}
+
+/* Main friend processor.  This is large, and for modularity purposes,
+   has been removed from grokdeclarator.  It returns `void_type_node'
+   to indicate that something happened, though a FIELD_DECL is
+   not returned.
+
+   CTYPE is the class this friend belongs to.
+
+   DECLARATOR is the name of the friend.
+
+   DECL is the FUNCTION_DECL that the friend is.
+
+   In case we are parsing a friend which is part of an inline
+   definition, we will need to store PARM_DECL chain that comes
+   with it into the DECL_ARGUMENTS slot of the FUNCTION_DECL.
+
+   FLAGS is just used for `grokclassfn'.
+
+   QUALS say what special qualifies should apply to the object
+   pointed to by `this'.  */
+
+tree
+do_friend (ctype, declarator, decl, parmdecls, flags, quals, funcdef_flag)
+     tree ctype, declarator, decl, parmdecls;
+     enum overload_flags flags;
+     tree quals;
+     int funcdef_flag;
+{
+  /* Every decl that gets here is a friend of something.  */
+  DECL_FRIEND_P (decl) = 1;
+
+  if (ctype)
+    {
+      tree cname = TYPE_NAME (ctype);
+      if (TREE_CODE (cname) == TYPE_DECL)
+	cname = DECL_NAME (cname);
+
+      /* A method friend.  */
+      if (TREE_CODE (decl) == FUNCTION_DECL)
+	{
+	  if (flags == NO_SPECIAL && ctype && declarator == cname)
+	    DECL_CONSTRUCTOR_P (decl) = 1;
+
+	  /* This will set up DECL_ARGUMENTS for us.  */
+	  grokclassfn (ctype, cname, decl, flags, quals);
+	  if (TYPE_SIZE (ctype) != 0)
+	    decl = check_classfn (ctype, decl);
+
+	  if (TREE_TYPE (decl) != error_mark_node)
+	    {
+	      if (TYPE_SIZE (ctype))
+		add_friend (current_class_type, decl);
+	      else
+		{
+		  cp_error ("member `%D' declared as friend before type `%T' defined",
+			    decl, ctype);
+		}
+	    }
+	}
+      else
+	{
+	  /* Possibly a bunch of method friends.  */
+
+	  /* Get the class they belong to.  */
+	  tree ctype = IDENTIFIER_TYPE_VALUE (cname);
+	  tree fields = lookup_fnfields (TYPE_BINFO (ctype), declarator, 0);
+
+	  if (fields)
+	    add_friends (current_class_type, declarator, ctype);
+	  else
+	    error ("method `%s' is not a member of class `%s'",
+		   IDENTIFIER_POINTER (declarator),
+		   IDENTIFIER_POINTER (cname));
+	  decl = void_type_node;
+	}
+    }
+  else if (TREE_CODE (decl) == FUNCTION_DECL
+	   && ((IDENTIFIER_LENGTH (declarator) == 4
+		&& IDENTIFIER_POINTER (declarator)[0] == 'm'
+		&& ! strcmp (IDENTIFIER_POINTER (declarator), "main"))
+	       || (IDENTIFIER_LENGTH (declarator) > 10
+		   && IDENTIFIER_POINTER (declarator)[0] == '_'
+		   && IDENTIFIER_POINTER (declarator)[1] == '_'
+		   && strncmp (IDENTIFIER_POINTER (declarator)+2,
+			       "builtin_", 8) == 0)))
+    {
+      /* raw "main", and builtin functions never gets overloaded,
+	 but they can become friends.  */
+      add_friend (current_class_type, decl);
+      DECL_FRIEND_P (decl) = 1;
+      decl = void_type_node;
+    }
+  /* A global friend.
+     @@ or possibly a friend from a base class ?!?  */
+  else if (TREE_CODE (decl) == FUNCTION_DECL)
+    {
+      /* Friends must all go through the overload machinery,
+	 even though they may not technically be overloaded.
+
+	 Note that because classes all wind up being top-level
+	 in their scope, their friend wind up in top-level scope as well.  */
+      DECL_ASSEMBLER_NAME (decl)
+	= build_decl_overload (declarator, TYPE_ARG_TYPES (TREE_TYPE (decl)),
+			       TREE_CODE (TREE_TYPE (decl)) == METHOD_TYPE);
+      DECL_ARGUMENTS (decl) = parmdecls;
+      if (funcdef_flag)
+	DECL_CLASS_CONTEXT (decl) = current_class_type;
+
+      /* We can call pushdecl here, because the TREE_CHAIN of this
+	 FUNCTION_DECL is not needed for other purposes.  */
+      decl = pushdecl (decl);
+
+      make_decl_rtl (decl, NULL_PTR, 1);
+      add_friend (current_class_type, decl);
+
+      DECL_FRIEND_P (decl) = 1;
+    }
+  else
+    {
+      /* @@ Should be able to ingest later definitions of this function
+	 before use.  */
+      tree decl = lookup_name_nonclass (declarator);
+      if (decl == NULL_TREE)
+	{
+	  warning ("implicitly declaring `%s' as struct",
+		   IDENTIFIER_POINTER (declarator));
+	  decl = xref_tag (record_type_node, declarator, NULL_TREE, 1);
+	  decl = TYPE_MAIN_DECL (decl);
+	}
+
+      /* Allow abbreviated declarations of overloaded functions,
+	 but not if those functions are really class names.  */
+      if (TREE_CODE (decl) == TREE_LIST && TREE_TYPE (TREE_PURPOSE (decl)))
+	{
+	  warning ("`friend %s' archaic, use `friend class %s' instead",
+		   IDENTIFIER_POINTER (declarator),
+		   IDENTIFIER_POINTER (declarator));
+	  decl = TREE_TYPE (TREE_PURPOSE (decl));
+	}
+
+      if (TREE_CODE (decl) == TREE_LIST)
+	add_friends (current_class_type, TREE_PURPOSE (decl), NULL_TREE);
+      else
+	make_friend_class (current_class_type, TREE_TYPE (decl));
+      decl = void_type_node;
+    }
+  return decl;
+}