[oe] meta-linaro and toolchain-layer

[Denys Dmytriyenko]

On Sat, Apr 07, 2012 at 02:08:38PM -0700, Khem Raj wrote:
> -----BEGIN PGP SIGNED MESSAGE-----
> Hash: SHA1
> 
> Hi,
> 
> Ken Werner @ Linaro has created a meta-linaro layer. I have created a
> github repo of same here https://github.com/kraj/meta-linaro

FWIW, I've been closely monitoring the progress of meta-linaro layer for past 
month and its status as applicable to meta-ti:

https://lists.yoctoproject.org/pipermail/meta-ti/2012-March/000747.html

When I tried it last time to build some of our machines in meta-ti, there were 
issues, but I didn't have time to follow up or investigate and I was busy with 
the BSP presentation at the time...

As a parallel effort, I was looking into working on the prebuilt toolchain 
support - i.e. recipes to use binary Linaro toolchain in OE/Yocto. I grabbed 
the latest 2012.03 release before leaving for the BSP Summit and Linux Collab 
and will give it a try ASAP.


> Moving forward soon gcc 4.7 will land in OE-Core and 4.6 will be
> more or less retired. In natural progression it would move to
> toolchain-layer if there are consumers of it.
> 
> linaro is also working on gcc-4.7 improvements in  same manner as
> 4.6  and there could be more tools e.g. gdb binutils etc. that could
> be useful for armv7+ from that layer.
> 
> I would like to propose few things we could do.
> 
> Use gcc-4.6 from meta-linaro and retire it from toolchain-layer
> which means toolchain layer only has gcc-4.5 and eventually
> This also means that we don't move gcc-4.6 into toolchain-layer
> when its relegated from OE-Core
> 
> In similar fashion add recipes for gcc-linaro-4.7 whenever linaro
> makes first 4.7 based release
> 
> Does anybody see downsides to this approach ?

Sounds like a decent plan, but we need to validate the newest toolchain 
versions with the real hardware before making the switch and dropping the old 
versions - 4.5 is still the most stable build for me and the broad range of 
architectures and platforms I work with at TI from ARM9 to Cortex-A15...


> This could mean that distro may have multiple compilers for different
> architectures e.g. linaro toolchain for arm
> architecture and may be OE-Core provided toolchain for rest of them
> 
> another option is that we do the same thing where we cherry-pick
> linaro patches into toolchain-layer and append them on top gcc from
> OE-Core which we have been doing with 4.6 it does mean extra work
> validation and maintenance that I would like to avoid.

-- 
Denys