diff --git a/scripts/kconfig/expr.h b/scripts/kconfig/expr.h
index 7c329e1..017843c 100644
--- a/scripts/kconfig/expr.h
+++ b/scripts/kconfig/expr.h
@@ -1,6 +1,6 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 /*
  * Copyright (C) 2002 Roman Zippel <zippel@linux-m68k.org>
- * Released under the terms of the GNU GPL v2.0.
  */
 
 #ifndef EXPR_H
@@ -62,7 +62,7 @@
 };
 
 enum symbol_type {
-	S_UNKNOWN, S_BOOLEAN, S_TRISTATE, S_INT, S_HEX, S_STRING, S_OTHER
+	S_UNKNOWN, S_BOOLEAN, S_TRISTATE, S_INT, S_HEX, S_STRING
 };
 
 /* enum values are used as index to symbol.def[] */
@@ -131,7 +131,7 @@
 	struct expr_value implied;
 };
 
-#define for_all_symbols(i, sym) for (i = 0; i < SYMBOL_HASHSIZE; i++) for (sym = symbol_hash[i]; sym; sym = sym->next) if (sym->type != S_OTHER)
+#define for_all_symbols(i, sym) for (i = 0; i < SYMBOL_HASHSIZE; i++) for (sym = symbol_hash[i]; sym; sym = sym->next)
 
 #define SYMBOL_CONST      0x0001  /* symbol is const */
 #define SYMBOL_CHECK      0x0008  /* used during dependency checking */
@@ -141,6 +141,7 @@
 #define SYMBOL_OPTIONAL   0x0100  /* choice is optional - values can be 'n' */
 #define SYMBOL_WRITE      0x0200  /* write symbol to file (KCONFIG_CONFIG) */
 #define SYMBOL_CHANGED    0x0400  /* ? */
+#define SYMBOL_WRITTEN    0x0800  /* track info to avoid double-write to .config */
 #define SYMBOL_NO_WRITE   0x1000  /* Symbol for internal use only; it will not be written */
 #define SYMBOL_CHECKED    0x2000  /* used during dependency checking */
 #define SYMBOL_WARNED     0x8000  /* warning has been issued */
@@ -172,7 +173,7 @@
  *         int "BAZ Value"
  *         range 1..255
  *
- * Please, also check zconf.y:print_symbol() when modifying the
+ * Please, also check parser.y:print_symbol() when modifying the
  * list of property types!
  */
 enum prop_type {