Re: [PATCH] kconfig: Document SYMBOL_OPTIONAL logic

From: Masahiro Yamada
Date: Thu Jan 18 2018 - 08:51:09 EST


2018-01-14 18:56 GMT+09:00 Ulf Magnusson <ulfalizer@xxxxxxxxx>:
> Not obvious, especially if you don't already know how choices are
> implemented.
>
> No functional changes. Only comments added.
>
> Signed-off-by: Ulf Magnusson <ulfalizer@xxxxxxxxx>
> ---
> scripts/kconfig/menu.c | 9 +++++++++
> 1 file changed, 9 insertions(+)
>
> diff --git a/scripts/kconfig/menu.c b/scripts/kconfig/menu.c
> index 92d3f06cd8a2..372eb5d9fef3 100644
> --- a/scripts/kconfig/menu.c
> +++ b/scripts/kconfig/menu.c
> @@ -548,6 +548,15 @@ void menu_finalize(struct menu *parent)
> sym->flags |= SYMBOL_WARNED;
> }
>
> + /*
> + * For non-optional choices, add a reverse dependency (corresponding to
> + * a select) of '<visibility> && m'. This prevents the user from
> + * setting the choice mode to 'n' when the choice is visible.
> + *
> + * This would also work for non-choice symbols, but only non-optional
> + * choices clear SYMBOL_OPTIONAL as of writing. Choices are implemented
> + * as a type of symbol.
> + */
> 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,
> --


Applied to linux-kbuild/kconfig. Thanks!



--
Best Regards
Masahiro Yamada