Improve dependency checks in kconfig

index 9d4cba1..455f2c8 100644
@@ -65,9 +65,13 @@ enum symbol_type {
 	S_UNKNOWN, S_BOOLEAN, S_TRISTATE, S_INT, S_HEX, S_STRING, S_OTHER
 };
 
+/* enum values are used as index to symbol.def[] */
 enum {
 	S_DEF_USER,		/* main user value */
-	S_DEF_AUTO,
+	S_DEF_AUTO,		/* values read from auto.conf */
+	S_DEF_DEF3,		/* Reserved for UI usage */
+	S_DEF_DEF4,		/* Reserved for UI usage */
+	S_DEF_COUNT
 };
 
 struct symbol {

@@ -75,7 +79,7 @@ struct symbol {
 	char *name;
 	enum symbol_type type;
 	struct symbol_value curr;
-	struct symbol_value def[4];
+	struct symbol_value def[S_DEF_COUNT];
 	tristate visible;
 	int flags;
 	struct property *prop;

index 455f2c8..0bdb58e 100644
@@ -88,22 +88,24 @@ struct symbol {
 
 #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_CONST		0x0001
-#define SYMBOL_CHECK		0x0008
-#define SYMBOL_CHOICE		0x0010
-#define SYMBOL_CHOICEVAL	0x0020
-#define SYMBOL_VALID		0x0080
-#define SYMBOL_OPTIONAL		0x0100
-#define SYMBOL_WRITE		0x0200
-#define SYMBOL_CHANGED		0x0400
-#define SYMBOL_AUTO		0x1000
-#define SYMBOL_CHECKED		0x2000
-#define SYMBOL_WARNED		0x8000
-#define SYMBOL_DEF		0x10000
-#define SYMBOL_DEF_USER		0x10000
-#define SYMBOL_DEF_AUTO		0x20000
-#define SYMBOL_DEF3		0x40000
-#define SYMBOL_DEF4		0x80000
+#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 */
 
 #define SYMBOL_MAXLENGTH	256
 #define SYMBOL_HASHSIZE		257

index 0bdb58e..6408fef 100644
@@ -111,21 +111,41 @@ struct symbol {
 #define SYMBOL_HASHSIZE		257
 #define SYMBOL_HASHMASK		0xff
 
+/* A property represent the config options that can be associated
+ * with a config "symbol".
+ * Sample:
+ * config FOO
+ *         default y
+ *         prompt "foo prompt"
+ *         select BAR
+ * config BAZ
+ *         int "BAZ Value"
+ *         range 1..255
+ */
 enum prop_type {
-	P_UNKNOWN, P_PROMPT, P_COMMENT, P_MENU, P_DEFAULT, P_CHOICE,
-	P_SELECT, P_RANGE, P_ENV
+	P_UNKNOWN,
+	P_PROMPT,   /* prompt "foo prompt" or "BAZ Value" */
+	P_COMMENT,  /* text associated with a comment */
+	P_MENU,     /* prompt associated with a menuconfig option */
+	P_DEFAULT,  /* default y */
+	P_CHOICE,   /* choice value */
+	P_SELECT,   /* select BAR */
+	P_RANGE,    /* range 7..100 (for a symbol) */
+	P_ENV,      /* value from environment variable */
 };
 
 struct property {
-	struct property *next;
-	struct symbol *sym;
-	enum prop_type type;
-	const char *text;
+	struct property *next;     /* next property - null if last */
+	struct symbol *sym;        /* the symbol for which the property is associated */
+	enum prop_type type;       /* type of property */
+	const char *text;          /* the prompt value - P_PROMPT, P_MENU, P_COMMENT */
 	struct expr_value visible;
-	struct expr *expr;
-	struct menu *menu;
-	struct file *file;
-	int lineno;
+	struct expr *expr;         /* the optional conditional part of the property */
+	struct menu *menu;         /* the menu the property are associated with
+	                            * valid for: P_SELECT, P_RANGE, P_CHOICE,
+	                            * P_PROMPT, P_DEFAULT, P_MENU, P_COMMENT */
+	struct file *file;         /* what file was this property defined */
+	int lineno;                /* what lineno was this property defined */
 };
 
 #define for_all_properties(sym, st, tok) \

index 6408fef..d587895 100644
@@ -132,6 +132,7 @@ enum prop_type {
 	P_SELECT,   /* select BAR */
 	P_RANGE,    /* range 7..100 (for a symbol) */
 	P_ENV,      /* value from environment variable */
+	P_SYMBOL,   /* where a symbol is defined */
 };
 
 struct property {

index 07ff8d1..aa0e2f2 100644
@@ -55,6 +55,8 @@ void menu_add_entry(struct symbol *sym)
 	*last_entry_ptr = menu;
 	last_entry_ptr = &menu->next;
 	current_entry = menu;
+	if (sym)
+		 menu_add_prop(P_SYMBOL, NULL, NULL, NULL);
 }
 
 void menu_end_entry(void)

index 18f3e5c..474dae2 100644
@@ -856,8 +856,9 @@ struct symbol *sym_check_deps(struct symbol *sym)
 	struct property *prop;
 
 	if (sym->flags & SYMBOL_CHECK) {
-		fprintf(stderr, "%s:%d:error: found recursive dependency: %s",
-		        sym->prop->file->name, sym->prop->lineno,
+		fprintf(stderr, "%s:%d:error: found recursive dependency:\n",
+		        sym->prop->file->name, sym->prop->lineno);
+		fprintf(stderr, "\t    %s\n",
 			sym->name ? sym->name : "<choice>");
 		return sym;
 	}

@@ -877,7 +878,9 @@ struct symbol *sym_check_deps(struct symbol *sym)
 	}
 
 	if (sym2) {
-		fprintf(stderr, " -> %s", sym->name ? sym->name : "<choice>");
+		fprintf(stderr, "\t -> %s (%s:%d)\n",
+		        sym->name ? sym->name : "<choice>",
+			sym->prop->file->name, sym->prop->lineno);
 		if (sym2 == sym) {
 			fprintf(stderr, "\n");
 			zconfnerrs++;

@@ -937,6 +940,8 @@ const char *prop_get_type_name(enum prop_type type)
 		return "select";
 	case P_RANGE:
 		return "range";
+	case P_SYMBOL:
+		return "symbol";
 	case P_UNKNOWN:
 		break;
 	}

index 474dae2..fc62f34 100644
@@ -790,6 +790,21 @@ static struct symbol *sym_check_expr_deps(struct expr *e)
 	return NULL;
 }
 
+static void print_symbol_location(struct symbol *sym)
+{
+	struct property *prop;
+	int comma = 0;
+
+	fprintf(stderr, "\t -> %s ", sym->name ? sym->name : "<choice>");
+	for (prop = sym->prop; prop; prop = prop->next) {
+		if (prop->type == P_SYMBOL) {
+			fprintf(stderr, "%s(%s:%d)",
+			comma ? "," : "", prop->file->name, prop->lineno);
+			comma = 1;
+		}
+	}
+	fprintf(stderr, "\n");
+}
 /* return NULL when dependencies are OK */
 static struct symbol *sym_check_sym_deps(struct symbol *sym)
 {

@@ -835,7 +850,7 @@ static struct symbol *sym_check_choice_deps(struct symbol *choice)
 	expr_list_for_each_sym(prop->expr, e, sym) {
 		sym2 = sym_check_sym_deps(sym);
 		if (sym2) {
-			fprintf(stderr, " -> %s", sym->name);
+			print_symbol_location(sym);
 			break;
 		}
 	}

@@ -856,7 +871,7 @@ struct symbol *sym_check_deps(struct symbol *sym)
 	struct property *prop;
 
 	if (sym->flags & SYMBOL_CHECK) {
-		fprintf(stderr, "%s:%d:error: found recursive dependency:\n",
+		fprintf(stderr, "%s:%d: found recursive dependency:\n",
 		        sym->prop->file->name, sym->prop->lineno);
 		fprintf(stderr, "\t    %s\n",
 			sym->name ? sym->name : "<choice>");

@@ -878,11 +893,8 @@ struct symbol *sym_check_deps(struct symbol *sym)
 	}
 
 	if (sym2) {
-		fprintf(stderr, "\t -> %s (%s:%d)\n",
-		        sym->name ? sym->name : "<choice>",
-			sym->prop->file->name, sym->prop->lineno);
+		print_symbol_location(sym);
 		if (sym2 == sym) {
-			fprintf(stderr, "\n");
 			zconfnerrs++;
 			sym2 = NULL;
 		}