--- gcc/c-common.c.orig	Mon Jan 24 12:10:00 2000
+++ gcc/c-common.c	Tue Feb  1 02:43:39 2000
@@ -152,7 +152,7 @@
 						 int, int, int));
 static void init_attributes		PARAMS ((void));
 static void record_function_format	PARAMS ((tree, tree, enum format_type,
-						 int, int));
+						 int, int, int));
 static void record_international_format	PARAMS ((tree, tree, int));
 static tree c_find_base_decl            PARAMS ((tree));
 static int default_valid_lang_attribute PARAMS ((tree, tree, tree, tree));
@@ -812,6 +812,7 @@
 	      = TREE_VALUE (TREE_CHAIN (TREE_CHAIN (args)));
 	    int format_num;
 	    int first_arg_num;
+	    int null_format_ok;
 	    enum format_type format_type;
 	    tree argument;
 	    int arg_num;
@@ -825,7 +826,7 @@
 
 	    if (TREE_CODE (format_type_id) != IDENTIFIER_NODE)
 	      {
-		error ("unrecognized format specifier");
+		error_with_decl (decl, "unrecognized format specifier");
 		continue;
 	      }
 	    else
@@ -833,12 +834,26 @@
 		const char *p = IDENTIFIER_POINTER (format_type_id);
 
 		if (!strcmp (p, "printf") || !strcmp (p, "__printf__"))
+		  {
+		  format_type = printf_format_type;
+		  null_format_ok = 0;
+		  }
+		else if (!strcmp (p, "printf0") || !strcmp (p, "__printf0__"))
+		  {
 		  format_type = printf_format_type;
+		  null_format_ok = 1;
+		  }
 		else if (!strcmp (p, "scanf") || !strcmp (p, "__scanf__"))
+		  {
 		  format_type = scanf_format_type;
+		  null_format_ok = 0;
+		  }
 		else if (!strcmp (p, "strftime")
 			 || !strcmp (p, "__strftime__"))
+		  {
 		  format_type = strftime_format_type;
+		  null_format_ok = 0;
+		  }
 		else
 		  {
 		    warning ("`%s' is an unrecognized format function type", p);
@@ -909,7 +924,8 @@
 
 	    record_function_format (DECL_NAME (decl),
 				    DECL_ASSEMBLER_NAME (decl),
-				    format_type, format_num, first_arg_num);
+				    format_type,  null_format_ok, format_num,
+				    first_arg_num);
 	    break;
 	  }
 
@@ -1213,6 +1229,11 @@
 } format_char_info;
 
 static format_char_info print_char_table[] = {
+/* FreeBSD kernel extensions.  */
+  { "D",	1,	T_C,	T_C,	NULL,	NULL,	NULL,	NULL,	NULL,	"-wp"		},
+  { "b",	1,	T_C,	T_C,	NULL,	NULL,	NULL,	NULL,	NULL,	"-wp"		},
+  { "rz",	0,	NULL,	T_I,	T_I,	T_L,	NULL,	NULL,	NULL,	"-wp0 +#"	},
+#define unextended_print_char_table	(print_char_table + 3)
   { "di",	0,	T_I,	T_I,	T_I,	T_L,	T_LL,	T_LL,	T_ST,	"-wp0 +"	},
   { "oxX",	0,	T_UI,	T_UI,	T_UI,	T_UL,	T_ULL,	T_ULL,	T_ST,	"-wp0#"		},
   { "u",	0,	T_UI,	T_UI,	T_UI,	T_UL,	T_ULL,	T_ULL,	T_ST,	"-wp0"		},
@@ -1273,6 +1294,7 @@
   tree name;			/* identifier such as "printf" */
   tree assembler_name;		/* optional mangled identifier (for C++) */
   enum format_type format_type;	/* type of format (printf, scanf, etc.) */
+  int null_format_ok;		/* TRUE if the format string may be NULL */
   int format_num;		/* number of format argument */
   int first_arg_num;		/* number of first arg (zero for varargs) */
 } function_format_info;
@@ -1305,25 +1327,25 @@
 init_function_format_info ()
 {
   record_function_format (get_identifier ("printf"), NULL_TREE,
-			  printf_format_type, 1, 2);
+			  printf_format_type, 0, 1, 2);
   record_function_format (get_identifier ("fprintf"), NULL_TREE,
-			  printf_format_type, 2, 3);
+			  printf_format_type, 0, 2, 3);
   record_function_format (get_identifier ("sprintf"), NULL_TREE,
-			  printf_format_type, 2, 3);
+			  printf_format_type, 0, 2, 3);
   record_function_format (get_identifier ("scanf"), NULL_TREE,
-			  scanf_format_type, 1, 2);
+			  scanf_format_type, 0, 1, 2);
   record_function_format (get_identifier ("fscanf"), NULL_TREE,
-			  scanf_format_type, 2, 3);
+			  scanf_format_type, 0, 2, 3);
   record_function_format (get_identifier ("sscanf"), NULL_TREE,
-			  scanf_format_type, 2, 3);
+			  scanf_format_type, 0, 2, 3);
   record_function_format (get_identifier ("vprintf"), NULL_TREE,
-			  printf_format_type, 1, 0);
+			  printf_format_type, 0, 1, 0);
   record_function_format (get_identifier ("vfprintf"), NULL_TREE,
-			  printf_format_type, 2, 0);
+			  printf_format_type, 0, 2, 0);
   record_function_format (get_identifier ("vsprintf"), NULL_TREE,
-			  printf_format_type, 2, 0);
+			  printf_format_type, 0, 2, 0);
   record_function_format (get_identifier ("strftime"), NULL_TREE,
-			  strftime_format_type, 3, 0);
+			  strftime_format_type, 0, 3, 0);
 
   record_international_format (get_identifier ("gettext"), NULL_TREE, 1);
   record_international_format (get_identifier ("dgettext"), NULL_TREE, 2);
@@ -1340,11 +1362,12 @@
    (e.g. for varargs such as vfprintf).  */
 
 static void
-record_function_format (name, assembler_name, format_type,
+record_function_format (name, assembler_name, format_type, null_format_ok,
 			format_num, first_arg_num)
       tree name;
       tree assembler_name;
       enum format_type format_type;
+      int null_format_ok;
       int format_num;
       int first_arg_num;
 {
@@ -1368,6 +1391,7 @@
     }
 
   info->format_type = format_type;
+  info->null_format_ok = null_format_ok;
   info->format_num = format_num;
   info->first_arg_num = first_arg_num;
 }
@@ -1521,7 +1545,8 @@
 
   if (integer_zerop (format_tree))
     {
-      warning ("null format string");
+      if (!info->null_format_ok)
+	warning ("null format string");
       return;
     }
   if (TREE_CODE (format_tree) != ADDR_EXPR)
@@ -1710,12 +1735,13 @@
 		     It will work on most machines, because size_t and int
 		     have the same mode.  But might as well warn anyway,
 		     since it will fail on other machines.  */
+		  /* XXX should we allow unsigned ints here?  */
 		  if ((TYPE_MAIN_VARIANT (TREE_TYPE (cur_param))
 		       != integer_type_node)
 		      &&
 		      (TYPE_MAIN_VARIANT (TREE_TYPE (cur_param))
 		       != unsigned_type_node))
-		    warning ("field width is not type int (arg %d)", arg_num);
+		    warning ("precision is not type int (arg %d)", arg_num);
 		}
 	    }
 	  else
@@ -1760,6 +1786,53 @@
 		}
 	    }
 	}
+      if (*format_chars == 'b')
+	{
+	  /* There should be an int arg to control the string arg.  */
+	  if (params == 0)
+	    {
+	      warning (tfaff);
+	      return;
+	    }
+	    if (info->first_arg_num != 0)
+	    {
+	      cur_param = TREE_VALUE (params);
+	      params = TREE_CHAIN (params);
+	      ++arg_num;
+	      if ((TYPE_MAIN_VARIANT (TREE_TYPE (cur_param))
+		   != integer_type_node)
+		  &&
+		  (TYPE_MAIN_VARIANT (TREE_TYPE (cur_param))
+		   != unsigned_type_node))
+		{
+		  warning ("bitmap is not type int (arg %d)", arg_num);
+		}
+	    }
+	}
+      if (*format_chars == 'D')
+	{
+	  /* There should be an unsigned char * arg before the string arg.  */
+	  if (params == 0)
+	    {
+	      warning (tfaff);
+	      return;
+	    }
+	    if (info->first_arg_num != 0)
+	    {
+	      cur_param = TREE_VALUE (params);
+	      params = TREE_CHAIN (params);
+	      ++arg_num;
+	      cur_type = TREE_TYPE (cur_param);
+	      if (TREE_CODE (cur_type) != POINTER_TYPE
+		  || TYPE_MAIN_VARIANT (TREE_TYPE (cur_type))
+		     != unsigned_char_type_node)
+		{
+		  warning ("ethernet address is not type unsigned char *"
+			   " (arg %d)",
+			   arg_num);
+		}
+	    }
+	}
 
       aflag = 0;
 
@@ -1828,7 +1901,8 @@
       switch (info->format_type)
 	{
 	case printf_format_type:
-	  fci = print_char_table;
+	  fci = flag_format_extensions ? print_char_table
+	  	: unextended_print_char_table;
 	  break;
 	case scanf_format_type:
 	  fci = scan_char_table;