[Buildroot] [RFC 1/1] br2-external: Alow to include toolchain from external tree

[Arnout Vandecappelle]

 Hi Yann,

On 20/04/2019 22:54, Yann E. MORIN wrote:
> Vadim, Arnout, All,
> 
> Here's my take on the topic (still WIP, but mostly there, needs commit
> log):
> 
>     https://git.buildroot.org/~ymorin/git/buildroot/log/?h=yem/br2-ext-toolchain
> 
> I'll be off until Monday, when I'll write proper commit log before
> submitting it.

 A few comments:

- The rule for internal variables being prefixed by BR_ instead of BR2_ is
written down, in some BR developer days report.

- Bikeshed: call the "dir" variable "outputdir" or something that makes it clear
it's the output.

- For the removal of prepare-kconfig, maybe mention that it reverts
9429e7b698638399ecfd73aa37545594f253a074

- I think it's worth adding a flag that checks if there is any external
toolchain at all, and to put a comment in br2-external.toolchains.in why it is
empty.

 Regards,
 Arnout