Re: [build bug, 2.6.24-rc1] CONFIG_VIDEO_DEV=m & CONFIG_VIDEO_SAA7146_VV=y

[Randy Dunlap <randy.dunlap@oracle.com>]

On Sat, 27 Oct 2007 23:30:57 +0200 Johannes Stezenbach wrote:

> On Fri, Oct 26, 2007, Ingo Molnar wrote:
> > 
> > the attached config (generated via make randconfig) fails to build due 
> > to the combination of these config entries:
> > 
> >   CONFIG_VIDEO_DEV=m
> >   CONFIG_VIDEO_SAA7146_VV=y
> > 
> > i found no obvious Kconfig way to force VIDEO_SAA7146_VV to be modular 
> > when VIDEO_DEV is modular - is there a good solution for this?
> 
> According to http://lkml.org/lkml/2007/10/21/226 :
> 
> config VIDEO_SAA7146_VV
> 	tristate
> 	depends on VIDEO_DEV = y || VIDEO_DEV = VIDEO_SAA7146_VV
> 	select VIDEOBUF_DMA_SG
> 	select VIDEO_SAA7146
> 
> (untested)

Nope, won't work.  I tried that last night.  VIDEO_DEV_SAA7146_VV
has too many "select"s involved, but select doesn't follow the dependency
chains.  IOW, as written in Documentation/kbuild/kconfig-language.txt:

	select is evil.... select will by brute force set a symbol
	equal to 'y' without visiting the dependencies. So abusing
	select you are able to select a symbol FOO even if FOO depends
	on BAR that is not set.


---
~Randy