kconfig: promote invalid numeric reference from warning to error

The Kconfig interpreter already warns if a numeric option attempts to use
a non-numeric option (bool, tristate, or string) to set its value (for
example, with a 'default' or 'range').

Since there is nowhere in the tree that attempts this, we can safely
promote this check from warning to error.

Assisted-by: LLM
Signed-off-by: Julian Braha <julianbraha@gmail.com>
Reviewed-by: Nicolas Schier <n.schier@fritz.com>
Link: https://patch.msgid.link/20260915211508.291790-2-julianbraha@gmail.com
Signed-off-by: Nathan Chancellor <nathan@kernel.org>

scripts/kconfig/lkc.h

@@ -89,7 +89,7 @@ struct property *menu_add_prompt(enum prop_type type, const char *prompt,
 				 struct expr *dep);
 void menu_add_expr(enum prop_type type, struct expr *expr, struct expr *dep);
 void menu_add_symbol(enum prop_type type, struct symbol *sym, struct expr *dep);
-void menu_finalize(void);
+int menu_finalize(void);
 void menu_set_type(int type);
 
 extern struct menu rootmenu;

scripts/kconfig/menu.c

@@ -240,11 +240,12 @@ static int menu_validate_number(struct symbol *sym, struct symbol *sym2)
 	       (sym2->type == S_UNKNOWN && sym_string_valid(sym, sym2->name));
 }
 
-static void sym_check_prop(struct symbol *sym)
+static int sym_check_prop(struct symbol *sym)
 {
 	struct property *prop;
 	struct symbol *sym2;
 	char *use;
+	int errors = 0;
 
 	for (prop = sym->prop; prop; prop = prop->next) {
 		switch (prop->type) {
@@ -258,10 +259,13 @@ static void sym_check_prop(struct symbol *sym)
 				break;
 			sym2 = prop_get_symbol(prop);
 			if (sym->type == S_HEX || sym->type == S_INT) {
-				if (!menu_validate_number(sym, sym2))
-					prop_warn(prop,
-					    "'%s': number is invalid",
-					    sym->name);
+				if (!menu_validate_number(sym, sym2)) {
+					fprintf(stderr,
+						"%s:%d: error: '%s': number is invalid\n",
+						prop->filename, prop->lineno,
+						sym->name);
+					errors++;
+				}
 			}
 			if (sym_is_choice(sym)) {
 				struct menu *choice = sym_get_choice_menu(sym2);
@@ -293,21 +297,28 @@ static void sym_check_prop(struct symbol *sym)
 				prop_warn(prop, "range is only allowed "
 						"for int or hex symbols");
 			if (!menu_validate_number(sym, prop->expr->left.sym) ||
-			    !menu_validate_number(sym, prop->expr->right.sym))
-				prop_warn(prop, "range is invalid");
+			    !menu_validate_number(sym, prop->expr->right.sym)) {
+				fprintf(stderr,
+					"%s:%d: error: range is invalid\n",
+					prop->filename, prop->lineno);
+				errors++;
+			}
 			break;
 		default:
 			;
 		}
 	}
+
+	return errors;
 }
 
-static void _menu_finalize(struct menu *parent, bool inside_choice)
+static int _menu_finalize(struct menu *parent, bool inside_choice)
 {
 	struct menu *menu, *last_menu;
 	struct symbol *sym;
 	struct property *prop;
 	struct expr *basedep, *dep, *dep2;
+	int errors = 0;
 
 	sym = parent->sym;
 	if (parent->list) {
@@ -393,7 +404,7 @@ static void _menu_finalize(struct menu *parent, bool inside_choice)
 		 * moving on
 		 */
 		for (menu = parent->list; menu; menu = menu->next)
-			_menu_finalize(menu, sym && sym_is_choice(sym));
+			errors += _menu_finalize(menu, sym && sym_is_choice(sym));
 	} else if (!inside_choice && sym) {
 		/*
 		 * Automatic submenu creation. If sym is a symbol and A, B, C,
@@ -461,7 +472,7 @@ static void _menu_finalize(struct menu *parent, bool inside_choice)
 			}
 			/* Superset, put in submenu */
 		next:
-			_menu_finalize(menu, false);
+			errors += _menu_finalize(menu, false);
 			menu->parent = parent;
 			last_menu = menu;
 		}
@@ -519,14 +530,16 @@ static void _menu_finalize(struct menu *parent, bool inside_choice)
 			menu_warn(parent, "config symbol defined without type");
 
 		/* Check properties connected to this symbol */
-		sym_check_prop(sym);
+		errors += sym_check_prop(sym);
 		sym->flags |= SYMBOL_WARNED;
 	}
+
+	return errors;
 }
 
-void menu_finalize(void)
+int menu_finalize(void)
 {
-	_menu_finalize(&rootmenu, false);
+	return _menu_finalize(&rootmenu, false);
 }
 
 bool menu_has_prompt(const struct menu *menu)

scripts/kconfig/parser.y

@@ -587,7 +587,7 @@ void conf_parse(const char *name)
 		menu_add_prompt(P_MENU, "Main menu", NULL);
 	}
 
-	menu_finalize();
+	yynerrs += menu_finalize();
 
 	menu_for_each_entry(menu) {
 		struct menu *child;

scripts/kconfig/tests/err_num_non_numeric_ref/Kconfig

@@ -0,0 +1,75 @@
+# SPDX-License-Identifier: GPL-2.0
+# Test non-numeric symbol references from numeric symbols
+
+config BOOL_SOURCE
+	bool
+
+config TRISTATE_SOURCE
+	tristate
+
+config STRING_SOURCE
+	string
+
+# Invalid int defaults
+
+config INT_DEFAULT_BOOL
+	int
+	default BOOL_SOURCE
+
+config INT_DEFAULT_TRISTATE
+	int
+	default TRISTATE_SOURCE
+
+config INT_DEFAULT_STRING
+	int
+	default STRING_SOURCE
+
+# Invalid hex defaults
+
+config HEX_DEFAULT_BOOL
+	hex
+	default BOOL_SOURCE
+
+config HEX_DEFAULT_TRISTATE
+	hex
+	default TRISTATE_SOURCE
+
+config HEX_DEFAULT_STRING
+	hex
+	default STRING_SOURCE
+
+# Invalid int ranges
+
+config INT_RANGE_BOOL
+	int
+	range BOOL_SOURCE 1
+
+config INT_RANGE_TRISTATE
+	int
+	range TRISTATE_SOURCE 1
+
+config INT_RANGE_STRING
+	int
+	range STRING_SOURCE 1
+
+config INT_RANGE_MULTIPLE
+	int
+	range BOOL_SOURCE TRISTATE_SOURCE
+
+# Invalid hex ranges
+
+config HEX_RANGE_BOOL
+	hex
+	range BOOL_SOURCE 0x1
+
+config HEX_RANGE_TRISTATE
+	hex
+	range TRISTATE_SOURCE 0x1
+
+config HEX_RANGE_STRING
+	hex
+	range STRING_SOURCE 0x1
+
+config HEX_RANGE_MULTIPLE
+	hex
+	range BOOL_SOURCE TRISTATE_SOURCE

scripts/kconfig/tests/err_num_non_numeric_ref/__init__.py

@@ -0,0 +1,9 @@
+# SPDX-License-Identifier: GPL-2.0
+"""
+Reject nonnumeric symbol references from int and hex properties.
+"""
+
+
+def test(conf):
+    assert conf.olddefconfig() == 1
+    assert conf.stderr_matches('expected_stderr')

scripts/kconfig/tests/err_num_non_numeric_ref/expected_stderr

@@ -0,0 +1,14 @@
+Kconfig:17: error: 'INT_DEFAULT_BOOL': number is invalid
+Kconfig:21: error: 'INT_DEFAULT_TRISTATE': number is invalid
+Kconfig:25: error: 'INT_DEFAULT_STRING': number is invalid
+Kconfig:31: error: 'HEX_DEFAULT_BOOL': number is invalid
+Kconfig:35: error: 'HEX_DEFAULT_TRISTATE': number is invalid
+Kconfig:39: error: 'HEX_DEFAULT_STRING': number is invalid
+Kconfig:45: error: range is invalid
+Kconfig:49: error: range is invalid
+Kconfig:53: error: range is invalid
+Kconfig:57: error: range is invalid
+Kconfig:63: error: range is invalid
+Kconfig:67: error: range is invalid
+Kconfig:71: error: range is invalid
+Kconfig:75: error: range is invalid