cp-tree.h (DECL_ANTICIPATED): New macro.

	* cp-tree.h (DECL_ANTICIPATED): New macro.
	Document new use of DECL_LANG_FLAG_7.
	* decl.c (builtin_function): Set DECL_ANTICIPATED on builtins
	in the user namespace.
	* lex.c (do_identifier): If the identifier's declaration has
	DECL_ANTICIPATED on, it has not yet been declared.  But do not
	replace it with an ordinary implicit declaration.

	* tinfo2.cc: Include stdlib.h.

From-SVN: r34267

gcc/cp/ChangeLog

+2000-05-30  Zack Weinberg  <zack@wolery.cumb.org>
+
+	* cp-tree.h (DECL_ANTICIPATED): New macro.
+	Document new use of DECL_LANG_FLAG_7.
+	* decl.c (builtin_function): Set DECL_ANTICIPATED on builtins
+	in the user namespace.
+	* lex.c (do_identifier): If the identifier's declaration has
+	DECL_ANTICIPATED on, it has not yet been declared.  But do not
+	replace it with an ordinary implicit declaration.             
+
+	* tinfo2.cc: Include stdlib.h.
+
 2000-05-29  Mark Mitchell  <mark@codesourcery.com>
 
 	* cp-tree.h (CLASSTYPE_ALIGN_UNIT): New macro.

gcc/cp/cp-tree.h

@@ -101,6 +101,7 @@ Boston, MA 02111-1307, USA.  */
    5: DECL_INTERFACE_KNOWN.
    6: DECL_THIS_STATIC (in VAR_DECL or FUNCTION_DECL).
    7: DECL_DEAD_FOR_LOCAL (in VAR_DECL).
+      DECL_ANTICIPATED (in FUNCTION_DECL).
 
    Usage of language-independent fields in a language-dependent manner:
    
@@ -2491,6 +2492,10 @@ extern int flag_new_for_scope;
 #define DECL_LOCAL_FUNCTION_P(NODE) \
   DECL_LANG_FLAG_0 (FUNCTION_DECL_CHECK (NODE))
 
+/* Nonzero if NODE is a FUNCTION_DECL for a built-in function, and we have
+   not yet seen a prototype for that function.  */
+#define DECL_ANTICIPATED(NODE) DECL_LANG_FLAG_7 (FUNCTION_DECL_CHECK (NODE))
+
 /* This _DECL represents a compiler-generated entity.  */
 #define SET_DECL_ARTIFICIAL(NODE) (DECL_ARTIFICIAL (NODE) = 1)
 

gcc/cp/decl.c

@@ -6770,6 +6770,12 @@ builtin_function (name, type, code, class, libname)
   if (libname)
     DECL_ASSEMBLER_NAME (decl) = get_identifier (libname);
   make_function_rtl (decl);
+
+  /* Warn if a function in the namespace for users
+     is used without an occasion to consider it declared.  */
+  if (name[0] != '_' || name[1] != '_')
+    DECL_ANTICIPATED (decl) = 1;
+
   return decl;
 }
 

gcc/cp/lex.c

@@ -3111,8 +3111,9 @@ do_identifier (token, parsing, args)
       id = lookup_name (token, 0);
       return error_mark_node;
     }
-      
-  if (!id)
+
+  if (!id || (TREE_CODE (id) == FUNCTION_DECL
+	      && DECL_ANTICIPATED (id)))
     {
       if (current_template_parms)
 	return build_min_nt (LOOKUP_EXPR, token);
@@ -3124,7 +3125,16 @@ do_identifier (token, parsing, args)
 	}
       else if (in_call && ! flag_strict_prototype)
 	{
-	  id = implicitly_declare (token);
+	  if (!id)
+	    id = implicitly_declare (token);
+	  else
+	    {
+	      /* Implicit declaration of built-in function.  Don't
+		 change the built-in declaration, but don't let this
+		 go by silently, either.  */
+	      cp_pedwarn ("implicit declaration of function `%D'", token);
+	      DECL_ANTICIPATED (id) = 0;  /* only issue this warning once */
+	    }
 	}
       else if (current_function_decl == 0)
 	{

gcc/cp/tinfo2.cc

@@ -28,6 +28,7 @@
 // the GNU General Public License.
 
 #include <stddef.h>
+#include <stdlib.h>		// for abort
 #include "tinfo.h"
 #include "new"			// for placement new