[Buildroot] How to rebuild following .config change?

[Grant Edwards <grant.b.edwards@gmail.com>]

On 2009-06-24, Thomas Petazzoni <thomas.petazzoni@free-electrons.com> wrote:
> Le Tue, 23 Jun 2009 20:05:06 +0000 (UTC),
> Grant Edwards <grant.b.edwards@gmail.com> a ??crit :
>
>> You can do a "distclean", but then all the sources get
>> re-downloaded and toolchains re-built -- which takes a _long_
>> time.
>
> It's true that Buildroot doesn't handle partial rebuilds very well.
> This is something we should improve.

Unfortunately, it's a very difficult problem -- especially for
something built up of several sort-of-independant subsystems.
It's pretty hard to automatically detect what depends on what
with 100% accuracy.

> In the mean time, here is how I use Buildroot :
>
>  * Set the BUILDROOT_DL_DIR environment variable, so that downloads are
>    made to a completely separate directory from the Buildroot source
>    and Buildroot build directories ;
>
>  * Use an external toolchain (such as one generated by Crosstool-NG,
>    for example). This way, the toolchain generation process is
>    independent from Buildroot, and you don't need to re-generate the
>    toolchain everytime you want to recompile the root filesystem from
>    scratch ;
>
>  * Use out-of-tree generation in Buildroot with "make
>    O=/path/to/somewhere". This way, all generated files are in a
>    separate directory, which makes it easy to clean everything.

Thanks, those are indeed valuable tips.

-- 
Grant Edwards                   grante             Yow! I am having FUN...
                                  at               I wonder if it's NET FUN or
                               visi.com            GROSS FUN?