Re: Using Debian sources
Hello Neil!
Thanks for your feedback!
(For the records on the ML: this is discussion about bug 437422:
http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=437422 )
On Wednesday 05 September 2007 14:30, you wrote:
> Building toolchains from the upstream sources for installation on
> Debian would appear to be asking for problems. Emdebian is building
> toolchains for cross-building using the Debian packages so that the
> toolchain should be more easily installable alongside the native
> toolchain. This also means that patches that may be needed for
> generating a cross-building toolchain can be committed upstream. This
> has also helped make gcc-4.2 build a "reverse cross" - where build !=
> host, host == target as opposed to the usual cross build of build ==
> host, host != target in order to provide libraries for installation
> alongside the packages built with the toolchain.
> So I'm not sure about crosstool-ng - I'm not sure where it would fit.
Interesting evaluation. But let me make my points, if you will:
- Regarding the build tools for Debian and its derivatives:
From the beginning, I was *not* regarding crosstool-NG as a replacement for
the build environement to build Debian and its derivatives.
crosstool-NG aims at being a convenient way of building toolchains, most
notably to embedded developpers, but also for all kind of projects. The
targeted system need not be running a Debian derivative. With crosstool-NG,
one can build a toolchain dedicated to its target machine, and use it to build
the software to run on it. Many projects, such as PDAs, routers,NASes and
other mebedded stuff may not have enough storage capability to hold a Debian
distribution (as is said on emdebian, most have a few Mebibytes of flash and
not much more RAM). So projects targetting these devices need to be able to
build specific toolchains, and carefully configured software, more often than
not with a dedicated and "home"-made build system.
- Regarding pushing patches upstream:
I don't have the time to push patches upstream (because I do that at home,
not at work). So I just 'vampirise' patches here and there, mostly from the
buildroot and the original crosstool. Some I did write myself.
Getting patches from the Debian packages seemed difficult to me as not all
patches are applied for all architectures (the gcc package has patches that
gets applied when targetting x86_64 but not when targetting MIPS, for
example). Unless I was mistaken... And I want the toolchains to be all built
with the same code base.
- Regarding what you call a "reverse cross":
crosstool-NG calls it "canadian cross" and is not yet functional. I'm working
on it, but this not the main interest of crosstool-NG right now, for the
reason explained above: targeted audience are those that want a toolchain to
cross-build software for their target, not necessarily those who want a
toolchain to run _on_ their target. But yet, I do know the need is there, as
I might soon have that need myself :-)
> Your website only mentions gcc-4.1 but Emdebian is currently updating to
> build 4.2.
Ah yes. The latest gcc was being used by most sample configurations, but the
table was not up-to-date. It now is. Thanks for pointing out the lag. :-)
On the other hand, this table is but an example of what is possible and that
I have tested. crosstool-NG does propose the latest versions, as well as some
older ones (under the OBSOLETE option), and even experimental versions (under
the EXPERIMENTAL option).
> http://www.emdebian.org/
Been there! Thanks for the pointer, I'll look more closely at what's going on
there.
> You are welcome to discuss toolchain-stuff on the debian-embedded
> mailing list or #emdebian IRC channel - details on the website.
ML in CC:.
> Another problem is that your website doesn't provide access to the SVN
> without checking out the sources locally so I can't look at the code.
> Would it be possible to install websvn or something similar so that
> interested visitors can take a look at the actual code?
In fact, the repository in browseable on-line already: the scheme used to
access the SVN repository is http, so you can at least browse the HEAD.
But as you suggested, I did install websvn, which is accessible from the
project page. Thanks for the hint!
> The Emdebian script that prepares our toolchains is visible at:
> http://buildd.emdebian.org/svn/browser/current/emdebian/trunk/buildcross/trunk
> and is currently being rewritten by Hector Oron (zumbi).
I'll have a look, thank you!
Again, Neil, thank you for your feedback!
Regards,
Yann E. MORIN.
PS. I'm not sure wether I should keep the bug report CC:ed, so feel free to
drop this CC: on subsequent replies.
YEM.
--
.-----------------.--------------------.------------------.--------------------.
| Yann E. MORIN | Real-Time Embedded | /"\ ASCII RIBBON | Erics' conspiracy: |
| +0/33 662376056 | Software Designer | \ / CAMPAIGN | ^ |
| --==< °_° >==-- °------------.-------: X AGAINST | /e\ There is no |
| http://ymorin.is-a-geek.org/ | (*_*) | / \ HTML MAIL | """ conspiracy. |
°------------------------------°-------°------------------°--------------------°
Reply to: