[Buildroot] Nearly duplicate builds

On 29-08-16 19:54, Steve Calfee wrote:

HI Arnout,

On Sat, Aug 27, 2016 at 4:46 AM, Arnout Vandecappelle [off-list ref] wrote:

quoted

 Hi Kenneth,

 What you're asking is unfortunately not simple...

snip

quoted

externally. Any host tools that are needed by this script can be included in the
external toolchain.

Please explain this line?

It seems to me with an external toolchain, the biggest overhead after
a make clean is the host tools (especially if you build the linux
kernel separately too). If you need python or some other big package
building the host stuff is a major time sink. It would be wonderful if
the host tools could also be external to the build like the toolchain.
I did not know they could be part of the external toolchain?

 You can build anything as part of the external toolchain. However, buildroot
doesn't recognize whatever you have built as something that is already
available. In other words, if something depends on the things that you added to
the external toolchain, it will just get built again instead of using the
version from the external toolchain.

 For the host tools that you use in a post-build or post-image script, however,
that doesn't matter, because it's not considered a dependency by buildroot.

 In the proposal I made, the post-image script would be used outside of
buildroot, so you have to make sure that any host tools you want to use are
either available on the system, or are part of the external toolchain. The
latter is IMHO simpler and easier to control.

 Regards,
 Arnout


-- 
Arnout Vandecappelle                          arnout at mind be
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