Re: [PATCH] kconfig: warn about complex selects

["Vegard Nossum" <vegard.nossum@gmail.com>]

On Sun, May 4, 2008 at 10:21 AM, Sam Ravnborg <sam@ravnborg.org> wrote:
>
> On Sun, May 04, 2008 at 07:40:44AM +0200, Vegard Nossum wrote:
>  > Hi,
>  >
>  > Given recent discussion about kconfig and the "select" feature, I have made
>  > the following quick & dirty patch to detect what I call "complex selects".
>  >
>  > For v2.6.25, I get these warnings:
>  > sound/pci/Kconfig:512:error: found complex select: SND_FM801_TEA575X -> VIDEO_V4L1
>  > drivers/ide/Kconfig:890:error: found complex select: ETRAX_IDE -> BLK_DEV_IDEDMA
>  > drivers/acpi/Kconfig:185:error: found complex select: ACPI_HOTPLUG_CPU -> ACPI_CONTAINER
>  >
>  > While for v2.6.26-rc1, I get these:
>  > sound/pci/Kconfig:528:error: found complex select: SND_FM801_TEA575X -> VIDEO_V4L1
>  > drivers/media/video/em28xx/Kconfig:2:error: found complex select: VIDEO_EM28XX -> MEDIA_TUNER
>  > drivers/media/video/bt8xx/Kconfig:2:error: found complex select: VIDEO_BT848 -> MEDIA_TUNER
>  > drivers/media/video/saa7134/Kconfig:2:error: found complex select: VIDEO_SAA7134 -> MEDIA_TUNER
>  > drivers/media/video/cx88/Kconfig:2:error: found complex select: VIDEO_CX88 -> MEDIA_TUNER
>  > drivers/media/video/cx23885/Kconfig:2:error: found complex select: VIDEO_CX23885 -> MEDIA_TUNER
>  > drivers/media/video/ivtv/Kconfig:2:error: found complex select: VIDEO_IVTV -> MEDIA_TUNER
>  > drivers/media/video/cx18/Kconfig:2:error: found complex select: VIDEO_CX18 -> MEDIA_TUNER
>  > drivers/media/video/pvrusb2/Kconfig:2:error: found complex select: VIDEO_PVRUSB2 -> MEDIA_TUNER
>  > drivers/media/video/Kconfig:690:error: found complex select: VIDEO_MXB -> MEDIA_TUNER
>  > drivers/media/video/usbvision/Kconfig:2:error: found complex select: VIDEO_USBVISION -> MEDIA_TUNER
>  > drivers/acpi/Kconfig:188:error: found complex select: ACPI_HOTPLUG_CPU -> ACPI_CONTAINER
>  >
>  > (In other words, the number of these has increased significantly since the
>  > last release, and these will probably be hit as compile errors at one point
>  > or another.)
>  >
>  > I am not a kconfig expert, so I might have missed some things. Roman, is this
>  > even remotely good? I think it's probably a good start anyway.
>
>  I did a small test of this using following configuration:
>  config A
>         bool "a"
>
>  config B
>         bool "b"
>         depends on A
>         default AA || AAA
>
>  config BB
>         bool "bb"
>         depends on A
>
>  config C
>         bool "c"
>         select B
>
>  config CC
>         bool "cc"
>         select BB
>
>
>  I had expected a warning about complex select for
>  both C and CC. But only C triggered the warning
>  due to the complex default value of B.
>  So we need to work on this a bit more.

Oops, yes. What I am checking is in fact only the "default" property,
not the "depends on". Hm. How to get the list of dependencies? :-)


Vegard

-- 
"The animistic metaphor of the bug that maliciously sneaked in while
the programmer was not looking is intellectually dishonest as it
disguises that the error is the programmer's own creation."
	-- E. W. Dijkstra, EWD1036