[Buildroot] [PATCH] change default location for local.mk to $(CONFIG_DIR)

[Arnout Vandecappelle <arnout@mind.be>]

On 03/14/13 09:37, Jeremy Rosen wrote:
>>
>>    But $(CONFIG_DIR) is not a good location then... $(CONFIG_DIR) is
>> $(TOPDIR) if doing in-tree build, and $(O) if doing out-of-tree
>> build.
>> When you delete your out-of-tree dir, local.mk will also be gone...
>>
>
> when you build out-of-tree, you want your config to be in the O=
> directory (that's the whole point of O= as I understand it) so when
> you remove that directory you loose your .config and thus all your
> customisation. It makes sense to have local.mk there too, since
> it's also customisation. But maybe I am missing something and that's
> not the point of O=

  Indeed, it does make sense. But on the other hand, when you do a 'make 
savedefconfig', the saved config still points to that local.mk.


> but in that case, what is the recommanded way of not having the .config
> in $(TOPDIR) ? is that not what I am supposed to do ? how can I save my
> .config in a git repo if I have to keep it in $(TOPDIR) which is already
> a buildroot repo ?

  Use savedefconfig to save a defconfig and copy that to the configs/ 
directory.


> I don't want to commit my .config in the buildroot repo because if I
> want to upstream my changes to $(TOPDIR) at any point, the changes to
> .config will be mangled in the middle. My philosophy is that $(TOPDIR)
> changes should only be potentially upstreamable stuff...

  I agree with your philosophy, but at the last BR develop days it was 
decided that we will recommend only one way of working, and that is to 
put everything (including non-upstreamable changes) in the buildroot 
directory. Note that we will try not to make the  other option impossible 
(cfr. Thomas's earlier comment about a potential use of local.mk).

  What we definitely _don't_ recommend, is putting an output dir or a 
.config under version control.

  So if your use case is that you want to put local.mk under version 
control, then you should change it from its default value in every 
configuration you have, and make it point to a per-project location, e.g. 
boards/mycompany/myboard/local.mk.



  Regards,
  Arnout


>>    I also don't really like the idea that with a defconfig, the build
>> result will be different when you change the O= command line
>> parameter.
>>
>
> again, I might misunderstand the point of O= but I thought that was the
> very idea behind it... have multiple projects sharing their $(TOPDIR),
> maybe their dl/ subdirectory, but not their .config
>
> there is no risk of accidentally using an incorrect O= since O= is only
> used for initialisation. After that, there is a makefile in $(CONFIG_DIR)
> that properly redirect you

-- 
Arnout Vandecappelle                          arnout at mind be
Senior Embedded Software Architect            +32-16-286500
Essensium/Mind                                http://www.mind.be
G.Geenslaan 9, 3001 Leuven, Belgium           BE 872 984 063 RPR Leuven
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