[PATCH 3/5] kconfig: improve error message for dependency between choice members

From: Masahiro Yamada
Date: Wed Jun 26 2024 - 14:23:05 EST


A choice member must not depend on another member within the same choice
block.

Kconfig detects this, but the error message is not sensible.

[Test Code]

choice
prompt "choose"

config A
bool "A"
depends on B

config B
bool "B"

endchoice

[Result]

Kconfig:1:error: recursive dependency detected!
Kconfig:1: choice <choice> contains symbol A
Kconfig:4: symbol A is part of choice B
Kconfig:8: symbol B is part of choice <choice>
For a resolution refer to Documentation/kbuild/kconfig-language.rst
subsection "Kconfig recursive dependency limitations"

The phrase "part of choice B" is weird because B is not a choice block,
but a choice member.

To determine whether the current symbol is a part of a choice block,
sym_is_choice(next_sym) must be checked.

This commit improves the error message to:

Kconfig:1:error: recursive dependency detected!
Kconfig:1: choice <choice> contains symbol A
Kconfig:4: symbol A symbol is visible depending on B
Kconfig:8: symbol B is part of choice <choice>
For a resolution refer to Documentation/kbuild/kconfig-language.rst
subsection "Kconfig recursive dependency limitations"

Signed-off-by: Masahiro Yamada <masahiroy@xxxxxxxxxx>
---

scripts/kconfig/symbol.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/scripts/kconfig/symbol.c b/scripts/kconfig/symbol.c
index 1cb8b6a22c5a..0c4b2894ac4e 100644
--- a/scripts/kconfig/symbol.c
+++ b/scripts/kconfig/symbol.c
@@ -1111,7 +1111,7 @@ static void sym_check_print_recursive(struct symbol *last_sym)
menu->filename, menu->lineno,
sym->name ? sym->name : "<choice>",
next_sym->name ? next_sym->name : "<choice>");
- } else if (sym_is_choice_value(sym)) {
+ } else if (sym_is_choice(next_sym)) {
fprintf(stderr, "%s:%d:\tsymbol %s is part of choice %s\n",
menu->filename, menu->lineno,
sym->name ? sym->name : "<choice>",
--
2.43.0