On 2016-06-08 17:38, Joe Perches wrote: > (Adding Michal Marek and linux-kbuild) > > On Wed, 2016-06-08 at 18:11 +0300, Vladimir Zapolskiy wrote: >> On 08.06.2016 16:53, Guenter Roeck wrote: >>> On 06/08/2016 06:37 AM, Vladimir Zapolskiy wrote: >>>>>> +comment "Watchdog Pretimeout Governors" >>>>>> + >>>>>> +config WATCHDOG_PRETIMEOUT_GOV >>>>>> + bool "Enable watchdog pretimeout governors" >>>>>> + default n >>>>> I don't think 'default n" is needed. >>>>> >>>> No strict objections, but probably 'default n' may save quite many >>>> lines in defconfigs. >>>> >>> I always wondered why it would be necessary to say "default n". >>> What is the difference between "default n" and no explicit default ? >>> >> I pointed out that it may have impact on defconfig, but experimentally >> it has no effect. >> >> Users of "make oldconfig" get a prompt in both cases as well. >> >> Also I haven't found any difference for silentoldconfig, olddefconfig >> and alldefconfig, I assume explicit "default n" and "def_bool n" >> can be safely dropped. Yes, 'default n' is a noop. > It's not completely clear removals are always appropriate. > > from: Documentation/kbuild/kconfig-language.txt: > ------------------------------------------------------------------ > - default value: "default" <expr> ["if" <expr>] > A config option can have any number of default values. If multiple > default values are visible, only the first defined one is active. > Default values are not limited to the menu entry where they are > defined. This means the default can be defined somewhere else or be > overridden by an earlier definition. > The default value is only assigned to the config symbol if no other > value was set by the user (via the input prompt above). If an input > prompt is visible the default value is presented to the user and can > be overridden by him. > Optionally, dependencies only for this default value can be added with > "if". > ------------------------------------------------------------------ > > Michal? Do you have an opinion or clarification? As Guenter explained, there can be multiple default statements with different if conditions. The first statement to match applies. Michal -- To unsubscribe from this list: send the line "unsubscribe linux-kbuild" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
