c-parse.in (OBJC_NEED_RAW_IDENTIFIER): Define macro and flag for contextualizing…

c-parse.in (OBJC_NEED_RAW_IDENTIFIER): Define macro and flag for contextualizing Objective-C class name lookup by the...

2001-08-01  Ziemowit Laski  <zlaski@apple.com>

        * c-parse.in (OBJC_NEED_RAW_IDENTIFIER): Define macro and flag for
	contextualizing Objective-C class name lookup by the lexer.
	(typespec_reserved_nonattr): Disable ObjC class name lookup after
	seeing a TYPESPEC.
	(protocoldef): Add support for forward @protocol declarations.
	(yylexname): Suppress ObjC class name lookup in certain contexts;
	re-enable after lookup is complete.
	(_yylex): Re-enable ObjC class name lookup when certain
	punctuation marks are seen.

	* objc/objc-act.c (check_protocol_recursively): New function used
	for finding circular dependencies in protocols.
	(objc_declare_protocols): New function for handling forward
	@protocol declarations.
	(receiver_is_class_object): Detect the case when 'self' is used
	inside of a class method.
	(build_message_expr): Issue a warning if class method is desired
	but instance method is found instead.
	(conforms_to_protocol): Streamline.
	(objc_comptypes): Detect the fact that 'Bar<Foo> foo' conforms to
	protocol Foo, even if 'Bar foo' does not.
	(check_protocols): Streamline.
	(start_protocol): Add checks for circular and duplicate protocol
	definitions.
	(encode_aggregate_within): For typedefs of structs, encode the
	underlying struct.
	* objc/objc-act.h (PROTOCOL_DEFINED): New tree accessor.
	(objc_declare_protocols): New prototype.

From-SVN: r44536

gcc/ChangeLog

+2001-08-01  Ziemowit Laski  <zlaski@apple.com>
+
+        * c-parse.in (OBJC_NEED_RAW_IDENTIFIER): Define macro and flag for
+	contextualizing Objective-C class name lookup by the lexer.
+	(typespec_reserved_nonattr): Disable ObjC class name lookup after
+	seeing a TYPESPEC.
+	(protocoldef): Add support for forward @protocol declarations.
+	(yylexname): Suppress ObjC class name lookup in certain contexts;
+	re-enable after lookup is complete.
+	(_yylex): Re-enable ObjC class name lookup when certain
+	punctuation marks are seen.
+
+	* objc/objc-act.c (check_protocol_recursively): New function used
+	for finding circular dependencies in protocols.
+	(objc_declare_protocols): New function for handling forward
+	@protocol declarations.
+	(receiver_is_class_object): Detect the case when 'self' is used
+	inside of a class method.
+	(build_message_expr): Issue a warning if class method is desired
+	but instance method is found instead.
+	(conforms_to_protocol): Streamline.
+	(objc_comptypes): Detect the fact that 'Bar<Foo> foo' conforms to
+	protocol Foo, even if 'Bar foo' does not.
+	(check_protocols): Streamline.
+	(start_protocol): Add checks for circular and duplicate protocol
+	definitions.
+	(encode_aggregate_within): For typedefs of structs, encode the
+	underlying struct.
+	* objc/objc-act.h (PROTOCOL_DEFINED): New tree accessor.
+	(objc_declare_protocols): New prototype.
+
 2001-08-01  Neil Booth  <neil@cat.daikokuya.demon.co.uk>
 
 	* cpphash.h (struct cpp_reader): New members line, pseudo_newlines.

gcc/c-parse.in

@@ -29,10 +29,10 @@ Boston, MA 02111-1307, USA.  */
    written by AT&T, but I have never seen it.  */
 
 ifobjc
-%expect 31
+%expect 31 /* shift/reduce conflicts, and 1 reduce/reduce conflict.  */
 end ifobjc
 ifc
-%expect 10
+%expect 10 /* shift/reduce conflicts, and no reduce/reduce conflicts.  */
 end ifc
 
 %{
@@ -295,8 +295,18 @@ int objc_receiver_context;
 int objc_public_flag;
 int objc_pq_context;
 
+/* The following flag is needed to contextualize ObjC lexical analysis.
+   In some cases (e.g., 'int NSObject;'), it is undesirable to bind 
+   an identifier to an ObjC class, even if a class with that name 
+   exists.  */
+int objc_need_raw_identifier;
+#define OBJC_NEED_RAW_IDENTIFIER(VAL)	objc_need_raw_identifier = VAL
 end ifobjc
 
+ifc
+#define OBJC_NEED_RAW_IDENTIFIER(VAL)	/* nothing */
+end ifc
+
 /* Tell yyparse how to print a token's value, if yydebug is set.  */
 
 #define YYPRINT(FILE,YYCHAR,YYLVAL) yyprint(FILE,YYCHAR,YYLVAL)
@@ -1384,6 +1394,7 @@ typespec_attr:
 
 typespec_reserved_nonattr:
 	  TYPESPEC
+		{ OBJC_NEED_RAW_IDENTIFIER (1);	}
 	| structsp_nonattr
 	;
 
@@ -1694,6 +1705,9 @@ parm_declarator_starttypename:
 	| parm_declarator_starttypename array_declarator  %prec '.'
 		{ $$ = set_array_declarator_type ($2, $1, 0); }
 	| TYPENAME
+ifobjc
+	| OBJECTNAME
+end ifobjc
 	;
 
 parm_declarator_nostarttypename:
@@ -2836,6 +2850,13 @@ protocoldef:
 		  finish_protocol(objc_interface_context);
 		  objc_interface_context = NULL_TREE;
 		}
+	/* The @protocol forward-declaration production introduces a
+	   reduce/reduce conflict on ';', which should be resolved in
+	   favor of the production 'identifier_list -> identifier'.  */
+	| PROTOCOL identifier_list ';'
+		{
+		  objc_declare_protocols ($2);
+		}
 	;
 
 protocolrefs:
@@ -3120,6 +3141,7 @@ keywordselector:
 selector:
 	  IDENTIFIER
 	| TYPENAME
+	| CLASSNAME
 	| OBJECTNAME
 	| reservedwords
 	;
@@ -3616,11 +3638,25 @@ yylexname ()
 {
   tree decl;
   
+ifobjc
+  int objc_force_identifier = objc_need_raw_identifier;
+  OBJC_NEED_RAW_IDENTIFIER (0);
+end ifobjc
+  
   if (C_IS_RESERVED_WORD (yylval.ttype))
     {
       enum rid rid_code = C_RID_CODE (yylval.ttype);
 
 ifobjc
+      /* Turn non-typedefed refs to "id" into plain identifiers; this
+	 allows constructs like "void foo(id id);" to work.  */
+      if (rid_code == RID_ID)
+      {
+	decl = lookup_name (yylval.ttype);
+	if (decl == NULL_TREE || TREE_CODE (decl) != TYPE_DECL)
+	  return IDENTIFIER;
+      }
+
       if (!OBJC_IS_AT_KEYWORD (rid_code)
 	  && (!OBJC_IS_PQ_KEYWORD (rid_code) || objc_pq_context))
 end ifobjc
@@ -3653,8 +3689,11 @@ ifobjc
   else
     {
       tree objc_interface_decl = is_class_name (yylval.ttype);
-
-      if (objc_interface_decl)
+      /* ObjC class names are in the same namespace as variables and
+	 typedefs, and hence are shadowed by local declarations.  */
+      if (objc_interface_decl 
+	  && (global_bindings_p () 
+	      || (!objc_force_identifier && !decl)))
 	{
 	  yylval.ttype = objc_interface_decl;
 	  return CLASSNAME;
@@ -3692,10 +3731,7 @@ _yylex ()
     case CPP_AND_AND:					return ANDAND;
     case CPP_OR_OR:					return OROR;
     case CPP_QUERY:					return '?';
-    case CPP_COLON:					return ':';
-    case CPP_COMMA:					return ',';
     case CPP_OPEN_PAREN:				return '(';
-    case CPP_CLOSE_PAREN:				return ')';
     case CPP_EQ_EQ:	yylval.code = EQ_EXPR;		return EQCOMPARE;
     case CPP_NOT_EQ:	yylval.code = NE_EXPR;		return EQCOMPARE;
     case CPP_GREATER_EQ:yylval.code = GE_EXPR;		return ARITHCOMPARE;
@@ -3716,7 +3752,6 @@ _yylex ()
     case CPP_CLOSE_SQUARE:				return ']';
     case CPP_OPEN_BRACE:				return '{';
     case CPP_CLOSE_BRACE:				return '}';
-    case CPP_SEMICOLON:					return ';';
     case CPP_ELLIPSIS:					return ELLIPSIS;
 
     case CPP_PLUS_PLUS:					return PLUSPLUS;
@@ -3724,6 +3759,13 @@ _yylex ()
     case CPP_DEREF:					return POINTSAT;
     case CPP_DOT:					return '.';
 
+      /* The following tokens may affect the interpretation of any
+	 identifiers following, if doing Objective-C.  */
+    case CPP_COLON:		OBJC_NEED_RAW_IDENTIFIER (0);	return ':';
+    case CPP_COMMA:		OBJC_NEED_RAW_IDENTIFIER (0);	return ',';
+    case CPP_CLOSE_PAREN:	OBJC_NEED_RAW_IDENTIFIER (0);	return ')';
+    case CPP_SEMICOLON:		OBJC_NEED_RAW_IDENTIFIER (0);	return ';';
+
     case CPP_EOF:
       if (cpp_pop_buffer (parse_in) == 0)
 	return 0;
@@ -3741,8 +3783,8 @@ _yylex ()
     case CPP_WSTRING:
       return STRING;
       
-      /* This token is Objective-C specific.  It gives the next
-	 token special significance.  */
+      /* This token is Objective-C specific.  It gives the next token
+	 special significance.  */
     case CPP_ATSIGN:
 ifobjc
       {

gcc/objc/objc-act.c

@@ -253,6 +253,7 @@ static tree build_selector_reference_decl	PARAMS ((void));
 
 static tree add_protocol			PARAMS ((tree));
 static tree lookup_protocol			PARAMS ((tree));
+static void check_protocol_recursively		PARAMS ((tree, tree));
 static tree lookup_and_install_protocols	PARAMS ((tree));
 
 /* Type encoding.  */
@@ -336,6 +337,8 @@ static tree check_duplicates			PARAMS ((hash));
 static tree receiver_is_class_object		PARAMS ((tree));
 static int check_methods			PARAMS ((tree, tree, int));
 static int conforms_to_protocol			PARAMS ((tree, tree));
+static void check_protocol			PARAMS ((tree, const char *,
+						       const char *));
 static void check_protocols			PARAMS ((tree, const char *,
 						       const char *));
 static tree encode_method_def			PARAMS ((tree));
@@ -1010,6 +1013,12 @@ objc_comptypes (lhs, rhs, reflexive)
 		      tree cat;
 
 		      rproto_list = CLASS_PROTOCOL_LIST (rinter);
+		      /* If the underlying ObjC class does not have
+			 protocols attached to it, perhaps there are
+			 "one-off" protocols attached to the rhs?
+			 E.g., 'id<MyProt> foo;'.  */
+		      if (!rproto_list)
+			rproto_list = TYPE_PROTOCOL_LIST (TREE_TYPE (rhs));
 		      rproto = lookup_protocol_in_reflist (rproto_list, p);
 
 		      /* Check for protocols adopted by categories.  */
@@ -1202,6 +1211,32 @@ get_object_reference (protocols)
   return type;
 }
 
+/* Check for circular dependencies in protocols.  The arguments are
+   PROTO, the protocol to check, and LIST, a list of protocol it
+   conforms to.  */
+
+static void 
+check_protocol_recursively (proto, list)
+     tree proto;
+     tree list;
+{
+  tree p;
+
+  for (p = list; p; p = TREE_CHAIN (p))
+    {
+      tree pp = TREE_VALUE (p);
+
+      if (TREE_CODE (pp) == IDENTIFIER_NODE)
+	pp = lookup_protocol (pp);
+
+      if (pp == proto)
+	fatal_error ("protocol `%s' has circular dependency",
+		     IDENTIFIER_POINTER (PROTOCOL_NAME (pp)));      
+      if (pp)
+	check_protocol_recursively (proto, PROTOCOL_LIST (pp));
+    }
+}
+
 static tree
 lookup_and_install_protocols (protocols)
      tree protocols;
@@ -4871,18 +4906,27 @@ check_duplicates (hsh)
   return meth;
 }
 
-/* If RECEIVER is a class reference, return the identifier node for the
-   referenced class.  RECEIVER is created by get_class_reference, so we
-   check the exact form created depending on which runtimes are used.  */
+/* If RECEIVER is a class reference, return the identifier node for
+   the referenced class.  RECEIVER is created by get_class_reference,
+   so we check the exact form created depending on which runtimes are
+   used.  */
 
 static tree
 receiver_is_class_object (receiver)
       tree receiver;
 {
   tree chain, exp, arg;
+
   if (flag_next_runtime)
     {
-      /* The receiver is a variable created by build_class_reference_decl.  */
+      /* The receiver is 'self' in the context of a class method.  */
+      if (objc_method_context
+	  && receiver == self_decl
+	  && TREE_CODE (objc_method_context) == CLASS_METHOD_DECL)
+	return CLASS_NAME (objc_implementation_context);
+
+      /* The receiver is a variable created by
+         build_class_reference_decl.  */
       if (TREE_CODE (receiver) == VAR_DECL
 	  && TREE_TYPE (receiver) == objc_class_type)
 	/* Look up the identifier.  */
@@ -4899,7 +4943,7 @@ receiver_is_class_object (receiver)
 	  && (exp = TREE_OPERAND (exp, 0))
 	  && TREE_CODE (exp) == FUNCTION_DECL
 	  && exp == objc_get_class_decl
-	  /* we have a call to objc_getClass! */
+	  /* We have a call to objc_getClass!  */
 	  && (arg = TREE_OPERAND (receiver, 1))
 	  && TREE_CODE (arg) == TREE_LIST
 	  && (arg = TREE_VALUE (arg)))
@@ -5143,7 +5187,8 @@ build_message_expr (mess)
 	    method_prototype = lookup_class_method_static (iface, sel_name);
 	}
 
-      if (!method_prototype)
+      if (!method_prototype 
+          || TREE_CODE (method_prototype) != CLASS_METHOD_DECL)
 	{
 	  warning ("cannot find class (factory) method.");
 	  warning ("return type for `%s' defaults to id",
@@ -5960,16 +6005,17 @@ check_methods (chain, list, mtype)
     return first;
 }
 
+/* Check if CLASS, or its superclasses, explicitly conforms to PROTOCOL.  */
+
 static int
 conforms_to_protocol (class, protocol)
      tree class;
      tree protocol;
 {
-   while (protocol)
+   if (TREE_CODE (protocol) == PROTOCOL_INTERFACE_TYPE)
      {
        tree p = CLASS_PROTOCOL_LIST (class);
-
-       while (p && TREE_VALUE (p) != TREE_VALUE (protocol))
+       while (p && TREE_VALUE (p) != protocol)
 	 p = TREE_CHAIN (p);
 
        if (!p)
@@ -5981,8 +6027,6 @@ conforms_to_protocol (class, protocol)
 	   if (!tmp)
 	     return 0;
 	 }
-
-       protocol = TREE_CHAIN (protocol);
      }
 
    return 1;
@@ -6054,29 +6098,32 @@ check_methods_accessible (chain, context, mtype)
     return first;
 }
 
+/* Check whether the current interface (accessible via
+   'implementation_context') actually implements protocol P, along
+   with any protocols that P inherits.  */
+   
 static void
-check_protocols (proto_list, type, name)
-     tree proto_list;
+check_protocol (p, type, name)
+     tree p;
      const char *type;
      const char *name;
 {
-  for ( ; proto_list; proto_list = TREE_CHAIN (proto_list))
-    {
-      tree p = TREE_VALUE (proto_list);
-
   if (TREE_CODE (p) == PROTOCOL_INTERFACE_TYPE)
     {
       int f1, f2;
 
-	  /* Ensure that all protocols have bodies.  */
-	  if (flag_warn_protocol) {
+      /* Ensure that all protocols have bodies!  */
+      if (flag_warn_protocol)
+	{
 	  f1 = check_methods (PROTOCOL_CLS_METHODS (p),
 			      CLASS_CLS_METHODS (implementation_context),
 			      '+');
 	  f2 = check_methods (PROTOCOL_NST_METHODS (p),
 			      CLASS_NST_METHODS (implementation_context),
 			      '-');
-	  } else {
+	}
+      else
+	{
 	  f1 = check_methods_accessible (PROTOCOL_CLS_METHODS (p),
 					 implementation_context,
 					 '+');
@@ -6088,24 +6135,45 @@ check_protocols (proto_list, type, name)
       if (!f1 || !f2)
 	warning ("%s `%s' does not fully implement the `%s' protocol",
 		 type, name, IDENTIFIER_POINTER (PROTOCOL_NAME (p)));
-
-	}
-      else
-        {
-	  ; /* An identifier if we could not find a protocol.  */
     }
     
   /* Check protocols recursively.  */
   if (PROTOCOL_LIST (p))
     {
-	  tree super_class
-	    = lookup_interface (CLASS_SUPER_NAME (implementation_template));
-	  if (! conforms_to_protocol (super_class, PROTOCOL_LIST (p)))
-	    check_protocols (PROTOCOL_LIST (p), type, name);
+      tree subs = PROTOCOL_LIST (p);
+      tree super_class =
+	lookup_interface (CLASS_SUPER_NAME (implementation_template));
+      while (subs) 
+	{
+	  tree sub = TREE_VALUE (subs);
+
+	  /* If the superclass does not conform to the protocols
+	     inherited by P, then we must!  */
+	  if (!super_class || !conforms_to_protocol (super_class, sub))
+	    check_protocol (sub, type, name);
+	  subs = TREE_CHAIN (subs);
 	}
     }
 }
 	
+/* Check whether the current interface (accessible via
+   'implementation_context') actually implements the protocols listed
+   in PROTO_LIST.  */
+   
+static void
+check_protocols (proto_list, type, name)
+     tree proto_list;
+     const char *type;
+     const char *name;
+{
+  for ( ; proto_list; proto_list = TREE_CHAIN (proto_list))
+    {
+      tree p = TREE_VALUE (proto_list);
+
+      check_protocol (p, type, name);
+    }
+}
+
 /* Make sure that the class CLASS_NAME is defined
    CODE says which kind of thing CLASS_NAME ought to be.
    It can be CLASS_INTERFACE_TYPE, CLASS_IMPLEMENTATION_TYPE,
@@ -6430,6 +6498,33 @@ lookup_protocol (ident)
   return NULL_TREE;
 }
 
+/* This function forward declares the protocols named by NAMES.  If
+   they are already declared or defined, the function has no effect.  */
+
+void
+objc_declare_protocols (names)
+     tree names;
+{
+  tree list;
+
+  for (list = names; list; list = TREE_CHAIN (list))
+    {
+      tree name = TREE_VALUE (list);
+
+      if (lookup_protocol (name) == NULL_TREE)
+	{
+	  tree protocol = make_node (PROTOCOL_INTERFACE_TYPE);
+
+	  TYPE_BINFO (protocol) = make_tree_vec (2);
+	  PROTOCOL_NAME (protocol) = name;
+	  PROTOCOL_LIST (protocol) = NULL_TREE;
+	  add_protocol (protocol);
+	  PROTOCOL_DEFINED (protocol) = 0;
+	  PROTOCOL_FORWARD_DECL (protocol) = NULL_TREE;
+	}
+    }
+}
+
 tree
 start_protocol (code, name, list)
      enum tree_code code;
@@ -6438,26 +6533,38 @@ start_protocol (code, name, list)
 {
   tree protocol;
 
-  /* This is as good a place as any.  Need to invoke push_tag_toplevel.  */
+  /* This is as good a place as any.  Need to invoke
+     push_tag_toplevel.  */
   if (!objc_protocol_template)
     objc_protocol_template = build_protocol_template ();
 
+  protocol = lookup_protocol (name);
+
+  if (!protocol)
+    {
       protocol = make_node (code);
       TYPE_BINFO (protocol) = make_tree_vec (2);
 
       PROTOCOL_NAME (protocol) = name;
-  PROTOCOL_LIST (protocol) = list;
+      PROTOCOL_LIST (protocol) = lookup_and_install_protocols (list);
+      add_protocol (protocol);
+      PROTOCOL_DEFINED (protocol) = 1;
+      PROTOCOL_FORWARD_DECL (protocol) = NULL_TREE;
 
-  lookup_and_install_protocols (list);
+      check_protocol_recursively (protocol, list);
+    }
+  else if (! PROTOCOL_DEFINED (protocol))
+    {
+      PROTOCOL_DEFINED (protocol) = 1;
+      PROTOCOL_LIST (protocol) = lookup_and_install_protocols (list);
 
-  if (lookup_protocol (name))
+      check_protocol_recursively (protocol, list);
+    }
+  else
+    {
       warning ("duplicate declaration for protocol `%s'",
 	       IDENTIFIER_POINTER (name));
-  else
-    add_protocol (protocol);
-
-  PROTOCOL_FORWARD_DECL (protocol) = NULL_TREE;
-
+    }
   return protocol;
 }
 
@@ -6595,6 +6702,11 @@ encode_aggregate_within (type, curtype, format, left, right)
      int left;
      int right;
 {
+  /* The RECORD_TYPE may in fact be a typedef!  For purposes
+     of encoding, we need the real underlying enchilada.  */
+  if (TYPE_MAIN_VARIANT (type))
+    type = TYPE_MAIN_VARIANT (type);
+
   if (obstack_object_size (&util_obstack) > 0
       && *(obstack_next_free (&util_obstack) - 1) == '^')
     {

gcc/objc/objc-act.h

 /* Declarations for objc-act.c.
-   Copyright (C) 1990, 2000 Free Software Foundation, Inc.
+   Copyright (C) 1990, 2000, 2001 Free Software Foundation, Inc.
 
 This file is part of GNU CC.
 
@@ -59,6 +59,7 @@ extern tree objc_ellipsis_node;
 
 void objc_declare_alias				PARAMS ((tree, tree));
 void objc_declare_class				PARAMS ((tree));
+void objc_declare_protocols			PARAMS ((tree));
 
 extern int objc_receiver_context;
 
@@ -101,6 +102,7 @@ tree build_encode_expr				PARAMS ((tree));
 #define PROTOCOL_NST_METHODS(CLASS) ((CLASS)->type.minval)
 #define PROTOCOL_CLS_METHODS(CLASS) ((CLASS)->type.maxval)
 #define PROTOCOL_FORWARD_DECL(CLASS) TREE_VEC_ELT (TYPE_BINFO (CLASS), 1)
+#define PROTOCOL_DEFINED(CLASS) TREE_USED (CLASS)
 #define TYPE_PROTOCOL_LIST(TYPE) ((TYPE)->type.context)
 
 /* Define the Objective-C or Objective-C++ language-specific tree codes.  */