[Buildroot] Using Buildroot tool chain as external Toolchain

[Thomas Petazzoni <thomas.petazzoni@free-electrons.com>]

Dear john,

On Tue, 14 May 2013 10:08:04 +0100, john wrote:

> I followed this process:
> 1. I downloaded a copy of buildroot-2012.05
> 2. Configured it and built it for my system
> 3. Confirmed that everything built and ran sucessfully
> 4. Copied the contents of buildroot-2012.05/output/host/usr
> to /apps/buildroot_toolchain/usr

This doesn't work. By default, gcc is linked dynamically against mpc,
mpfr and al, and that doesn't work nicely if you move things around.

Two choices:

 *) Build mpc and mpfr statically, so that gcc is linked statically
    against them. Ideally, we should allow them to be built
    dynamically, but gcc/binutils have binaries in multiple locations
    in the tree, so we can't use the $ORIGIN/../lib trick to support a
    relocatable rpath.

 *) Set BR2_HOST_DIR directly to /apps/buildroot_toolchain/ so that
    your toolchain gets built and installed directly in this location.

> arm-linux-gcc... /home/xxx/xxx/xxx/buildroot-2012.05/output/host/usr/bin/arm-unknown-linux-uclibcgnueabi-gcc
> checking whether the C compiler works... no
> configure: error: in
> `/home/xxx/xxx/xxx/buildroot-2012.05/output/build/alsa-lib-1.0.25':
> configure: error: C compiler cannot create executables
> See `config.log' for more details
> make: ***
> [/home/xxx/xxx/xxx/buildroot-2012.05/output/build/alsa-lib-1.0.25/.stamp_configured]
> Error 77

See output/build/alsa-lib-1.0.25/config.log for the details of the
error; Would be useful to have this information to confirm that my
analysis above is correct.

Thanks,

Thomas
-- 
Thomas Petazzoni, Free Electrons
Kernel, drivers, real-time and embedded Linux
development, consulting, training and support.
http://free-electrons.com