-#define for_all_symbols(i, sym) for (i = 0; i < 257; i++) for (sym = symbol_hash[i]; sym; sym = sym->next) if (sym->type != S_OTHER)
-
-#define SYMBOL_YES 0x0001
-#define SYMBOL_MOD 0x0002
-#define SYMBOL_NO 0x0004
-#define SYMBOL_CONST 0x0007
-#define SYMBOL_CHECK 0x0008
-#define SYMBOL_CHOICE 0x0010
-#define SYMBOL_CHOICEVAL 0x0020
-#define SYMBOL_PRINTED 0x0040
-#define SYMBOL_VALID 0x0080
-#define SYMBOL_OPTIONAL 0x0100
-#define SYMBOL_WRITE 0x0200
-#define SYMBOL_CHANGED 0x0400
-#define SYMBOL_NEW 0x0800
-#define SYMBOL_AUTO 0x1000
-#define SYMBOL_CHECKED 0x2000
-#define SYMBOL_WARNED 0x8000
+#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 SYMBOL_CONST 0x0001 /* symbol is const */
+#define SYMBOL_CHECK 0x0008 /* used during dependency checking */
+#define SYMBOL_CHOICE 0x0010 /* start of a choice block (null name) */
+#define SYMBOL_CHOICEVAL 0x0020 /* used as a value in a choice block */
+#define SYMBOL_VALID 0x0080 /* set when symbol.curr is calculated */
+#define SYMBOL_OPTIONAL 0x0100 /* choice is optional - values can be 'n' */
+#define SYMBOL_WRITE 0x0200 /* ? */
+#define SYMBOL_CHANGED 0x0400 /* ? */
+#define SYMBOL_AUTO 0x1000 /* value from environment variable */
+#define SYMBOL_CHECKED 0x2000 /* used during dependency checking */
+#define SYMBOL_WARNED 0x8000 /* warning has been issued */
+
+/* Set when symbol.def[] is used */
+#define SYMBOL_DEF 0x10000 /* First bit of SYMBOL_DEF */
+#define SYMBOL_DEF_USER 0x10000 /* symbol.def[S_DEF_USER] is valid */
+#define SYMBOL_DEF_AUTO 0x20000 /* symbol.def[S_DEF_AUTO] is valid */
+#define SYMBOL_DEF3 0x40000 /* symbol.def[S_DEF_3] is valid */
+#define SYMBOL_DEF4 0x80000 /* symbol.def[S_DEF_4] is valid */