On 2014-05-16 06:42, Paul Eggleton wrote:
On Friday 16 May 2014 05:31:41 Gary Thomas wrote:
On 2014-05-16 05:16, Paul Eggleton wrote:
On Friday 16 May 2014 04:50:47 Gary Thomas wrote:
On 2014-05-15 14:53, Richard Purdie wrote:
On Wed, 2014-05-14 at 12:06 -0600, Gary Thomas wrote:
I have a number of platforms which [for whatever reason]
need older versions of GCC. I've been supporting this by
keeping the older code around in my own layers - I need
4.7.x for some targets, even 4.6.x for others.
With the changes in the latest master (post 1.6/daisy), I
am no longer able to build those older compilers :-( First
I had to fix up some core changes to just get the recipes to
even parse (bb.utils.contains), but now I get a slew of errors
like these:
NOTE: preferred version 4.7% of libgcc-initial not available (for
item libgcc-initial) NOTE: versions of libgcc-initial available:
4.8.2 4.9.0
I looked at the old recipes and they don't provide these
packages which make them unsuitable.
I know I should move these targets to the newer GCC, but at
this moment there simply are not the resources to do so, but
we still want to benefit from other improvements in OE-core
(and Poky/Yocto).
How can I move forward? Is there some way to retrofit the
older compilers into the new [required] structures? Perhaps
I could use the older compilers as external tool chain, but
the last time I tried to use this (in place of the internal,
build in place) tools, I could never make things happy :-(
Any suggestions more than welcome, thanks
How are you doing this? Have you a completely separate set of gcc
recipes including the include files or is this using the current include
files. You basically have two options:
I made a complete copy of recipes-devtools/gcc before the original 4.8
recipes were added.
a) Apply the changes that were made in master gcc to the 4.7 recipes,
you can then probably share includes.
b) Use a separate set of 4.7 files and "undo" some of the changes in
master using creative variable names. E.g., libgcc-initial was added:
recipes-core/eglibc/eglibc-initial.inc:DEPENDS = "linux-libc-headers
virtual/${TARGET_PREFIX}gcc-initial libgcc-initial"
recipes-core/eglibc/eglibc.inc:DEPENDS =
"virtual/${TARGET_PREFIX}gcc-initial libgcc-initial linux-libc-headers
virtual/${TARGET_PREFIX}libc-initial"
so you could do a:
DEPENDS_remove_pn-eglibc-initial - "libgcc-initial"
DEPENDS_remove_pn-eglibc - "libgcc-initial"
Thinking a bit more, the issue that is going to hit you hard are the -PN
additions to the cross recipe changes (and their change in arch). My
strong recommendation is therefore a) and then replaying the gcc changes
made in master against the 4.7 version. These were:
http://git.yoctoproject.org/cgit.cgi/poky/log/meta/recipes-devtools/gcc
there are about 10 or so changes there you'd need to check in your 4.7
recipes (since the 25th April) but nothing particularly difficult.
Thanks for these pointers. I've given them a quick look and indeed
they look manageable, so I'll probably give them a go.
Do you know if anyone has ever [successfully!] used an existing
Poky/Yocto toolchain via the EXTERNAL_TOOLCHAIN method, like is
done by the meta-sourcery layers/tools? I would think that would
be my safest bet - capture a working toolchain (I use both 4.6.3
and 4.7.2) and then enable the external support with the appropriate
toolchain/version (captured and managed out of band) for the targets
that need them. How hard might this be?
We don't support this usage at the moment in OE; if you use the OE
toolchain we recommend you let the system build it, and it will then be
restored from shared state for subsequent builds. I searched around for
discussion on this>
and coincidentally I turned up a thread you were on a few years ago:
http://comments.gmane.org/gmane.linux.embedded.poky/7049
There was some discussion at the OEDAM meeting recently about trying to
bring this back, but I'm pretty sure Richard is keen to avoid going down
that path for the same reasons we've been avoiding it so far.
I looked back through this thread and the enhancement bug I filed
(which for everyone but Richard seemed to be the way to go). The
result was to reuse sstate, but I don't see how that can solve the
problem I have today. How can I possibly create sstate cache files
for my old GCC/4.6.3 toolchain and allow them to be used with the
latest builds?
Well, it's true that sstate won't help you solve that problem since the recipe
still needs to be buildable (i.e. all dependencies need to be satisfied);
sstate is rather the answer to "I want an external toolchain to avoid having
to build the toolchain on every new build" which is a different problem.
However, the recipes for an external toolchain must satisfy the exact same
dependencies, so maintaining your old toolchain recipes isn't a whole lot
different than an external toolchain at least in that respect, although you
might argue that that maintenance would be taken care of by someone else
rather you having to do it.
BTW, in the meta-openembedded repository there is a toolchain-layer layer that
was intended to provide older versions of gcc; I think it hasn't been used
much lately so it may have bitrotted, but it may be helpful for people like
yourself who need older toolchains to club together and bring it up-to-date.
I just tried the meta-sourcery (old CSL) layer and it worked a treat.
I only had to add that layer and define a single variable to point to
their tools. Next week, I think I'll have a go at adapting their layer
to use an OE derived toolchain.
--
------------------------------------------------------------
Gary Thomas | Consulting for the
MLB Associates | Embedded world
------------------------------------------------------------
--
_______________________________________________
yocto mailing list
[email protected]
https://lists.yoctoproject.org/listinfo/yocto
