2018-01-12 06:48:10

by Ulf Magnusson

Subject: [PATCH] kconfig: Warn if there is more than one help text

Avoids mistakes like in the following real-world example, where only the
final help string ("Say Y...") was used. This particular example was
fixed in commit 561b29e4ec8d ("media: fix media Kconfig help syntax
issues").

config DVB_NETUP_UNIDVB
...
select DVB_CXD2841ER if MEDIA_SUBDRV_AUTOSELECT
---help---
Support for NetUP PCI express Universal DVB card.
help
Say Y when you want to support NetUP Dual Universal DVB card
...

This now prints the following warning:

drivers/media/pci/netup_unidvb:13: warning: 'DVB_NETUP_UNIDVB' defined with more than one help text -- only the last one will be used

Also free() any extra help strings.

Signed-off-by: Ulf Magnusson <[email protected]>
---
scripts/kconfig/zconf.y | 5 +++++
1 file changed, 5 insertions(+)

diff --git a/scripts/kconfig/zconf.y b/scripts/kconfig/zconf.y
index c1e4e82f56b5..06ef304ee325 100644
--- a/scripts/kconfig/zconf.y
+++ b/scripts/kconfig/zconf.y
@@ -435,6 +435,11 @@ help_start: T_HELP T_EOL

help: help_start T_HELPTEXT
{
+ if (current_entry->help) {
+ free(current_entry->help);
+ zconfprint("warning: '%s' defined with more than one help text -- only the last one will be used",
+ current_entry->sym->name ?: "<choice>");
+ }
current_entry->help = $2;
};

--
2.14.1

2018-01-13 13:19:44

by Masahiro Yamada

Subject: Re: [PATCH] kconfig: Warn if there is more than one help text

2018-01-12 15:47 GMT+09:00 Ulf Magnusson <[email protected]>:
> Avoids mistakes like in the following real-world example, where only the
> final help string ("Say Y...") was used. This particular example was
> fixed in commit 561b29e4ec8d ("media: fix media Kconfig help syntax
> issues").
>
> config DVB_NETUP_UNIDVB
> ...
> select DVB_CXD2841ER if MEDIA_SUBDRV_AUTOSELECT
> ---help---
> Support for NetUP PCI express Universal DVB card.
> help
> Say Y when you want to support NetUP Dual Universal DVB card
> ...
>
> This now prints the following warning:
>
> drivers/media/pci/netup_unidvb:13: warning: 'DVB_NETUP_UNIDVB' defined with more than one help text -- only the last one will be used
>
> Also free() any extra help strings.
>
> Signed-off-by: Ulf Magnusson <[email protected]>
> ---

Applied to linux-kbuild/kconfig
replacing "kconfig: Don't leak help strings during parsing"

Thanks!

--
Best Regards
Masahiro Yamada