Re: lfs -> Ubuntu cross compiler w/ apt?

On Mon, Feb 6, 2012 at 3:08 AM, Nathan Coulson <[email protected]> wrote:
> I built myself a compiler that can compile binaries for ubuntu (using
> their libraries).  Originally I just used the standard LFS compiler,
> but later on had a few messages that I believe were complaining that
> my glibc was newer then ubuntu's.  (was long ago,  don't quite recall
> the exact message).
>
> To work around this, I built a
>
> First, I grabbed a few of the ubuntu .deb files, and converted them w/
> the deb2tgz utility.
>
> install -d -m755 /usr/x86_64-ubuntu1104-linux-gnu/sysroot
>
> tar -xf src/libc6_2.13-0ubuntu13_amd64.tar.xz -C
> /usr/x86_64-ubuntu1104-linux-gnu/sysroot
> tar -xf src/libc6-i386_2.13-0ubuntu13_amd64.tar.xz -C
> /usr/x86_64-ubuntu1104-linux-gnu/sysroot
> tar -xf src/libc6-dev_2.13-0ubuntu13_amd64.tar.xz -C
> /usr/x86_64-ubuntu1104-linux-gnu/sysroot
> tar -xf src/libc6-dev-i386_2.13-0ubuntu13_amd64.tar.xz -C
> /usr/x86_64-ubuntu1104-linux-gnu/sysroot
> tar -xf src/linux-libc-dev_2.6.38-11.48_amd64.tar.xz -C
> /usr/x86_64-ubuntu1104-linux-gnu/sysroot
> tar -xf src/ia32-libs_20090808ubuntu13_amd64.tar.xz -C
> /usr/x86_64-ubuntu1104-linux-gnu/sysroot
> tar -xf src/libltdl7_2.2.6b-2ubuntu3_amd64.tar.xz -C
> /usr/x86_64-ubuntu1104-linux-gnu/sysroot
>
> fixed up a few absolute symlinks,
>
> rm /usr/x86_64-ubuntu1104-linux-gnu/sysroot/lib64
> ln -sv lib /usr/x86_64-ubuntu1104-linux-gnu/sysroot/lib64
> #fix absolute symlinks
> cd /usr/x86_64-ubuntu1104-linux-gnu/sysroot/usr/lib/x86_64-linux-gnu
> for x in *; do if [ -h "$x" ];then LINK=../..`readlink $x`; ln -sf
> $LINK $x; fi; done
> cd /usr/x86_64-ubuntu1104-linux-gnu/sysroot/usr/lib/
> ln -sf x86_64-linux-gnu/* .
> cd /usr/x86_64-ubuntu1104-linux-gnu/sysroot/lib
> ln -sf x86_64-linux-gnu/* .
>
> rm /usr/x86_64-ubuntu1104-linux-gnu/sysroot/usr/include/asm
> ln -sfv x86_64-linux-gnu/asm
> /usr/x86_64-ubuntu1104-linux-gnu/sysroot/usr/include/asm
>
> then rebuilt binutils/gcc using the sysroot flag  (I used the same
> versions from LFS, so perhaps a bit newer then ubuntu's)
> ../binutils-${BINUTILS_VERSION}/configure --prefix=/usr \
>  --target=x86_64-ubuntu1104-linux-gnu \
>  --with-sysroot=/usr/x86_64-ubuntu1104-linux-gnu/sysroot &&
> make &&
> make install &&
>
> ../gcc-${GCC_VERSION}/configure --prefix=/usr \
>  --target=x86_64-ubuntu1104-linux-gnu \
>  --with-sysroot=/usr/x86_64-ubuntu1104-linux-gnu/sysroot \
>  --enable-shared --enable-threads=posix \
>  --enable-__cxa_atexit --enable-languages=c \
>  --disable-libstdcxx-pch \
>  --enable-long-long \
>  --disable-libgomp --disable-libquadmath \
>  --without-ppl --without-cloog &&
> make -j6 &&
> make install &&
>
> (I based this upon my linux -> mingw64 compiler, may have a few extra
> flags.   I'll have to investigate later.  although I don't think I
> disabled any features I actually use)
>
>
>
>
>
>
> It works fine and dandy, but I was wondering if I should be worrying
> about the updates in ubuntu, and how hard it would be to setup an apt
> repository and just pull the updates directly from ubuntu into a
> sysroot folder.  Would save time compared to hunting down the .deb's
> then converting them manually.

Decided to polish my response a bit

To work around the fact that ubuntu apparantly chose to use different
versions then I decided to,  I built a cross compiler via sysroot.

The code I fixed the absolute symlinks was subpar,  replaced with the
following (been using this for half a year, wonder when I messed that
up)

echo > build_relink.sh << "EOF"
  ln -svf ../../..`readlink $1` $1
"EOF"
chmod 755 build_relink.sh

find  /usr/x86_64-ubuntu1104-linux-gnu/sysroot/usr/lib/x86_64-linux-gnu \
   -lname '/*' -exec ./build_relink.sh '{}' ';'


and fixed up gcc to use less flags
../gcc-${GCC_VERSION}/configure --prefix=/usr \
  --target=x86_64-ubuntu1104-linux-gnu \
  --with-sysroot=/usr/x86_64-ubuntu1104-linux-gnu/sysroot \
  --enable-shared --enable-threads=posix \
  --enable-__cxa_atexit --enable-languages=c \
  --enable-long-long &&
make -j6 &&
make install &&


-- 
Nathan Coulson (conathan)
------
Location: British Columbia, Canada
Timezone: PST (-8)
Webpage: http://www.nathancoulson.com
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