? o
Index: c-format.c
===================================================================
RCS file: /cvsroot/src/external/gpl3/gcc.old/dist/gcc/c-family/c-format.c,v
retrieving revision 1.4
diff -u -u -r1.4 c-format.c
--- c-format.c	23 Jul 2017 01:10:59 -0000	1.4
+++ c-format.c	11 Sep 2018 18:27:00 -0000
@@ -823,70 +823,70 @@
     printf_flag_specs, printf_flag_pairs,
     FMT_FLAG_ARG_CONVERT|FMT_FLAG_DOLLAR_MULTIPLE|FMT_FLAG_USE_DOLLAR|FMT_FLAG_EMPTY_PREC_OK,
     'w', 0, 'p', 0, 'L', 0,
-    &integer_type_node, &integer_type_node
+    &integer_type_node, &integer_type_node, format_type_error
   },
   { "asm_fprintf",   asm_fprintf_length_specs,  asm_fprintf_char_table, " +#0-", NULL,
     asm_fprintf_flag_specs, asm_fprintf_flag_pairs,
     FMT_FLAG_ARG_CONVERT|FMT_FLAG_EMPTY_PREC_OK,
     'w', 0, 'p', 0, 'L', 0,
-    NULL, NULL
+    NULL, NULL, format_type_error
   },
   { "gcc_diag",   gcc_diag_length_specs,  gcc_diag_char_table, "q+#", NULL,
     gcc_diag_flag_specs, gcc_diag_flag_pairs,
     FMT_FLAG_ARG_CONVERT|FMT_FLAG_M_OK,
     0, 0, 'p', 0, 'L', 0,
-    NULL, &integer_type_node
+    NULL, &integer_type_node, format_type_error
   },
   { "gcc_tdiag",   gcc_tdiag_length_specs,  gcc_tdiag_char_table, "q+#", NULL,
     gcc_tdiag_flag_specs, gcc_tdiag_flag_pairs,
     FMT_FLAG_ARG_CONVERT|FMT_FLAG_M_OK,
     0, 0, 'p', 0, 'L', 0,
-    NULL, &integer_type_node
+    NULL, &integer_type_node, format_type_error
   },
   { "gcc_cdiag",   gcc_cdiag_length_specs,  gcc_cdiag_char_table, "q+#", NULL,
     gcc_cdiag_flag_specs, gcc_cdiag_flag_pairs,
     FMT_FLAG_ARG_CONVERT|FMT_FLAG_M_OK,
     0, 0, 'p', 0, 'L', 0,
-    NULL, &integer_type_node
+    NULL, &integer_type_node, format_type_error
   },
   { "gcc_cxxdiag",   gcc_cxxdiag_length_specs,  gcc_cxxdiag_char_table, "q+#", NULL,
     gcc_cxxdiag_flag_specs, gcc_cxxdiag_flag_pairs,
     FMT_FLAG_ARG_CONVERT|FMT_FLAG_M_OK,
     0, 0, 'p', 0, 'L', 0,
-    NULL, &integer_type_node
+    NULL, &integer_type_node, format_type_error
   },
   { "gcc_gfc", gcc_gfc_length_specs, gcc_gfc_char_table, "q+#", NULL,
     gcc_gfc_flag_specs, gcc_gfc_flag_pairs,
     FMT_FLAG_ARG_CONVERT|FMT_FLAG_M_OK,
     0, 0, 0, 0, 0, 0,
-    NULL, NULL
+    NULL, NULL, format_type_error
   },
   { "NSString",   NULL,  NULL, NULL, NULL,
     NULL, NULL,
     FMT_FLAG_ARG_CONVERT|FMT_FLAG_PARSE_ARG_CONVERT_EXTERNAL, 0, 0, 0, 0, 0, 0,
-    NULL, NULL
+    NULL, NULL, format_type_error
   },
   { "gnu_scanf",    scanf_length_specs,   scan_char_table,  "*'I", NULL,
     scanf_flag_specs, scanf_flag_pairs,
     FMT_FLAG_ARG_CONVERT|FMT_FLAG_SCANF_A_KLUDGE|FMT_FLAG_USE_DOLLAR|FMT_FLAG_ZERO_WIDTH_BAD|FMT_FLAG_DOLLAR_GAP_POINTER_OK,
     'w', 0, 0, '*', 'L', 'm',
-    NULL, NULL
+    NULL, NULL, format_type_error
   },
   { "gnu_strftime", NULL,                 time_char_table,  "_-0^#", "EO",
     strftime_flag_specs, strftime_flag_pairs,
     FMT_FLAG_FANCY_PERCENT_OK|FMT_FLAG_M_OK, 'w', 0, 0, 0, 0, 0,
-    NULL, NULL
+    NULL, NULL, format_type_error
   },
   { "gnu_strfmon",  strfmon_length_specs, monetary_char_table, "=^+(!-", NULL,
     strfmon_flag_specs, strfmon_flag_pairs,
     FMT_FLAG_ARG_CONVERT, 'w', '#', 'p', 0, 'L', 0,
-    NULL, NULL
+    NULL, NULL, format_type_error
   },
   { "gnu_syslog",   printf_length_specs,  print_char_table, " +#0-'I", NULL,
     printf_flag_specs, printf_flag_pairs,
     FMT_FLAG_ARG_CONVERT|FMT_FLAG_DOLLAR_MULTIPLE|FMT_FLAG_USE_DOLLAR|FMT_FLAG_EMPTY_PREC_OK|FMT_FLAG_M_OK,
     'w', 0, 'p', 0, 'L', 0,
-    &integer_type_node, &integer_type_node
+    &integer_type_node, &integer_type_node, printf_format_type
   },
 };
 
@@ -1033,18 +1033,22 @@
 		params = tree_cons (NULL_TREE, argarray[i], params);
 	      check_format_info (&info, params);
 	    }
+	  format_kind_info *fi = &format_types[info.format_type];
 	  if (warn_suggest_attribute_format && info.first_arg_num == 0
-	      && (format_types[info.format_type].flags
-		  & (int) FMT_FLAG_ARG_CONVERT))
+	      && (fi->flags & (int) FMT_FLAG_ARG_CONVERT))
 	    {
 	      tree c;
 	      for (c = TYPE_ATTRIBUTES (TREE_TYPE (current_function_decl));
 		   c;
 		   c = TREE_CHAIN (c))
-		if (is_attribute_p ("format", TREE_PURPOSE (c))
-		    && (decode_format_type (IDENTIFIER_POINTER
-					    (TREE_VALUE (TREE_VALUE (c))))
-			== info.format_type))
+		if (!is_attribute_p ("format", TREE_PURPOSE (c)))
+		   continue;
+		int format_type = decode_format_type (
+		    IDENTIFIER_POINTER (TREE_VALUE (TREE_VALUE (c))));
+		if (format_type == format_type_error)
+		   continue;
+		if (format_type == info.format_type ||
+		    format_type == fi->parent_format_type)
 		  break;
 	      if (c == NULL_TREE)
 		{
@@ -1065,7 +1069,7 @@
 		  if (args != 0)
 		    warning (OPT_Wsuggest_attribute_format, "function might "
 			     "be possible candidate for %qs format attribute",
-			     format_types[info.format_type].name);
+			     fi->name);
 		}
 	    }
 	}
Index: c-format.h
===================================================================
RCS file: /cvsroot/src/external/gpl3/gcc.old/dist/gcc/c-family/c-format.h,v
retrieving revision 1.4
diff -u -u -r1.4 c-format.h
--- c-format.h	23 Jul 2017 01:10:59 -0000	1.4
+++ c-format.h	11 Sep 2018 18:27:00 -0000
@@ -253,6 +253,8 @@
   /* Pointer to type of argument expected if '*' is used for a precision,
      or NULL if '*' not used for precisions.  */
   tree *precision_type;
+  /* A format type that is a subset of our format */
+  int	parent_format_type;
 } format_kind_info;
 
 #define T_I	&integer_type_node