Re: Cross compiler ITP (armel)

[Loïc Minier <lool@dooz.org>]

        Hi

 (We also had separate discussions Hector, Matthias and I, sometimes
 including debian-embedded@ and/or Neil Williams -- I'm catching up on
 the debian-devel@ thread.)

On Sun, Nov 01, 2009, Hector Oron wrote:
>   I would like to do a little explanation on the ITP I have filled for
> {linux,binutils,eglibc,gcc-4.3,gcc-4.4,gdb}-armel.

 Another approach which Matthias suggested (IIRC) is to use a single
 source package build-depending on all -source packages to build the
 cross-toolchain with a single upload.  With the split sources approach,
 you need something like 7 uploads to bootstrap the toolchain (I'm not
 counting gdb), and a close number if any of linux, binutils, eglibc or
 gcc change.  A single source package would be very heavy to build, but
 would be more effective.

 I worked on a linux/binutils/eglibc/gcc as separate source packages
 implementation recently, based on the Ubuntu toolchain (basically
 identical to Debian's for this discussion).  The resulting tree is at:
    bzr co lp:~lool/+junk/cross-toolchain
 and some binary packages for armel are available in my PPA, albeit
 these still suffer from a couple of important issues.

>   In order to avoid code duplication in the archive, this packages
> build depend on -source packages.

 I don't actually like the amount of logic/duplication with the
 toolchain source I ended up with; instead, it would make more sense to
 extend the rules in the real packages (gcc, eglibc, binutils etc.) to
 be able to produce first stage, second stage etc. cross-compilers and
 call them from a new cross-toolchain package.  I would also like to
 propose to change the -source packages to ship original .dsc, .diff.gz
 etc. instead of a patched or unpatched tarball with or without patches
 and/or rules to apply the patches.

>   As major technical issues,  I would try to build cross compilers
> with --sysroot support, but that means dpkg-cross need to be updated
> for sysroot paths. For now, we might take the road we have been doing
> at emdebian.org (for many years) and start changing bits towards a
> nice sysrooted solution.

 As we already discussed in private email, I find sysroot an interesting
 path forward, especially knowing that --with-headers/--with-libs is
 deprecated upstream, but I believe it's an orthogonal change which
 should be implemented in the toolchain as time permits.  I would also
 prefer relocatable toolchains, but using the cross-compiler locations
 is fine for now.


 I'd love to help on this cross-toolchain project for Debian and
 Ubuntu's uses and will look at discussing it with Matthias and other
 interested parties at UDS next week.

   Thanks,
-- 
Loïc Minier