[PATCH] add more warnings

Add a number of warnings to avoid misuse of the previously added features
(most important check for recursive dependencies).

scripts/kconfig/expr.h

@@ -92,6 +92,9 @@ struct symbol {
 #define SYMBOL_CHANGED		0x0400
 #define SYMBOL_NEW		0x0800
 #define SYMBOL_AUTO		0x1000
+#define SYMBOL_CHECKED		0x2000
+#define SYMBOL_CHECK_DONE	0x4000
+#define SYMBOL_WARNED		0x8000
 
 #define SYMBOL_MAXLENGTH	256
 #define SYMBOL_HASHSIZE		257

scripts/kconfig/menu.c

@@ -94,7 +94,7 @@ void menu_set_type(int type)
 		sym->type = type;
 		return;
 	}
-	fprintf(stderr, "%s:%d: type of '%s' redefined from '%s' to '%s'\n",
+	fprintf(stderr, "%s:%d:warning: type of '%s' redefined from '%s' to '%s'\n",
 		current_entry->file->name, current_entry->lineno,
 		sym->name ? sym->name : "<choice>", sym_type_name(sym->type), sym_type_name(type));
 }
@@ -248,6 +248,47 @@ void menu_finalize(struct menu *parent)
 		}
 	}
 
+	if (sym && !(sym->flags & SYMBOL_WARNED)) {
+		struct symbol *sym2;
+		if (sym->type == S_UNKNOWN)
+			fprintf(stderr, "%s:%d:warning: config symbol defined without type\n",
+				parent->file->name, parent->lineno);
+
+		if (sym_is_choice(sym) && !parent->prompt)
+			fprintf(stderr, "%s:%d:warning: choice must have a prompt\n",
+				parent->file->name, parent->lineno);
+
+		for (prop = sym->prop; prop; prop = prop->next) {
+			switch (prop->type) {
+			case P_DEFAULT:
+				if ((sym->type == S_STRING || sym->type == S_INT || sym->type == S_HEX) &&
+				    prop->expr->type != E_SYMBOL)
+					fprintf(stderr, "%s:%d:warning: default must be a single symbol\n",
+						prop->file->name, prop->lineno);
+				break;
+			case P_SELECT:
+				sym2 = prop_get_symbol(prop);
+				if ((sym->type != S_BOOLEAN && sym->type != S_TRISTATE) ||
+				    (sym2->type != S_BOOLEAN && sym2->type != S_TRISTATE))
+					fprintf(stderr, "%s:%d:warning: enable is only allowed with boolean and tristate symbols\n",
+						prop->file->name, prop->lineno);
+				break;
+			case P_RANGE:
+				if (sym->type != S_INT && sym->type != S_HEX)
+					fprintf(stderr, "%s:%d:warning: range is only allowed for int or hex symbols\n",
+						prop->file->name, prop->lineno);
+				if (!sym_string_valid(sym, prop->expr->left.sym->name) ||
+				    !sym_string_valid(sym, prop->expr->right.sym->name))
+					fprintf(stderr, "%s:%d:warning: range is invalid\n",
+						prop->file->name, prop->lineno);
+				break;
+			default:
+				;
+			}
+		}
+		sym->flags |= SYMBOL_WARNED;
+	}
+
 	if (sym && !sym_is_optional(sym) && parent->prompt) {
 		sym->rev_dep.expr = expr_alloc_or(sym->rev_dep.expr,
 				expr_alloc_and(parent->prompt->visible.expr,

scripts/kconfig/symbol.c

@@ -651,6 +651,74 @@ struct symbol *sym_find(const char *name)
 	return symbol;
 }
 
+struct symbol *sym_check_deps(struct symbol *sym);
+
+static struct symbol *sym_check_expr_deps(struct expr *e)
+{
+	struct symbol *sym;
+
+	if (!e)
+		return NULL;
+	switch (e->type) {
+	case E_OR:
+	case E_AND:
+		sym = sym_check_expr_deps(e->left.expr);
+		if (sym)
+			return sym;
+		return sym_check_expr_deps(e->right.expr);
+	case E_NOT:
+		return sym_check_expr_deps(e->left.expr);
+	case E_EQUAL:
+	case E_UNEQUAL:
+		sym = sym_check_deps(e->left.sym);
+		if (sym)
+			return sym;
+		return sym_check_deps(e->right.sym);
+	case E_SYMBOL:
+		return sym_check_deps(e->left.sym);
+	default:
+		break;
+	}
+	printf("Oops! How to check %d?\n", e->type);
+	return NULL;
+}
+
+struct symbol *sym_check_deps(struct symbol *sym)
+{
+	struct symbol *sym2;
+	struct property *prop;
+
+	if (sym->flags & SYMBOL_CHECK_DONE)
+		return NULL;
+	if (sym->flags & SYMBOL_CHECK) {
+		printf("Warning! Found recursive dependency: %s", sym->name);
+		return sym;
+	}
+
+	sym->flags |= (SYMBOL_CHECK | SYMBOL_CHECKED);
+	sym2 = sym_check_expr_deps(sym->rev_dep.expr);
+	if (sym2)
+		goto out;
+
+	for (prop = sym->prop; prop; prop = prop->next) {
+		if (prop->type == P_CHOICE)
+			continue;
+		sym2 = sym_check_expr_deps(prop->visible.expr);
+		if (sym2)
+			goto out;
+		if (prop->type != P_DEFAULT || sym_is_choice(sym))
+			continue;
+		sym2 = sym_check_expr_deps(prop->expr);
+		if (sym2)
+			goto out;
+	}
+out:
+	if (sym2)
+		printf(" %s", sym->name);
+	sym->flags &= ~SYMBOL_CHECK;
+	return sym2;
+}
+
 struct property *prop_alloc(enum prop_type type, struct symbol *sym)
 {
 	struct property *prop;

scripts/kconfig/zconf.tab.c_shipped

@@ -1915,6 +1915,9 @@ yyreturn:
 
 void conf_parse(const char *name)
 {
+	struct symbol *sym;
+	int i;
+
 	zconf_initscan(name);
 
 	sym_init();
@@ -1927,6 +1930,12 @@ void conf_parse(const char *name)
 	if (zconfnerrs)
 		exit(1);
 	menu_finalize(&rootmenu);
+	for_all_symbols(i, sym) {
+                if (!(sym->flags & SYMBOL_CHECKED) && sym_check_deps(sym))
+                        printf("\n");
+		else
+			sym->flags |= SYMBOL_CHECK_DONE;
+        }
 
 	sym_change_count = 1;
 }

scripts/kconfig/zconf.y

@@ -477,6 +477,9 @@ symbol:	  T_WORD	{ $$ = sym_lookup($1, 0); free($1); }
 
 void conf_parse(const char *name)
 {
+	struct symbol *sym;
+	int i;
+
 	zconf_initscan(name);
 
 	sym_init();
@@ -489,6 +492,12 @@ void conf_parse(const char *name)
 	if (zconfnerrs)
 		exit(1);
 	menu_finalize(&rootmenu);
+	for_all_symbols(i, sym) {
+                if (!(sym->flags & SYMBOL_CHECKED) && sym_check_deps(sym))
+                        printf("\n");
+		else
+			sym->flags |= SYMBOL_CHECK_DONE;
+        }
 
 	sym_change_count = 1;
 }