[Buildroot] Can Buildroot be configured to use the ELDK toolchain as an External Toolchain?

[Buildroot] Can Buildroot be configured to use the ELDK toolchain as an External Toolchain?

[Davis Mcpherson]

I'm working on a project that is using the ELDK toolchain and would like to use these tools to build Buildroot, I followed the instructions to configure an external toolchain via 'make menuconfig' but when I do 'make' i get an error that the the c library has been specified, i'm using glibc

but I think the problem is rooted in the SYSROOT value being used to verify glibc...

has anyone configured Buildroot to use ELDK as the external toolchain to use for builds? 

thanks,

davis mcpherson

[Buildroot] Can Buildroot be configured to use the ELDK toolchain as an External Toolchain?

[Thomas Petazzoni]

Hello Davis,

On Tue, 25 Jan 2011 18:44:58 -0500
Davis Mcpherson <davis.mcpherson@gmail.com> wrote:
 
> I'm working on a project that is using the ELDK toolchain and would
> like to use these tools to build Buildroot, I followed the
> instructions to configure an external toolchain via 'make menuconfig'
> but when I do 'make' i get an error that the the c library has been
> specified, i'm using glibc

Unfortunately, last time I checked, the ELDK toolchains did not support
the --sysroot option, which is mandatory to use a given toolchain as an
external toolchain in Buildroot. We have tried to support non
sysroot-capable toolchains, but it was the source of various issues,
and since sysroot is now quite ancient and available in most
toolchains, it sounded like a reasonable tradeoff.

> but I think the problem is rooted in the SYSROOT value being used to
> verify glibc...
> 
> has anyone configured Buildroot to use ELDK as the external toolchain
> to use for builds? 

I wanted to, but I never understood how to get just the ELDK toolchain
and not a complete distribution. I'll try to see if I can test this
toolchain, but if you have some simple setup instructions to get just
the toolchain, that would be great.

Thanks,

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

[Buildroot] Can Buildroot be configured to use the ELDK toolchain as an External Toolchain?

[Thomas Petazzoni]

On Wed, 26 Jan 2011 08:45:47 +0100
Thomas Petazzoni <thomas.petazzoni@free-electrons.com> wrote:

> Unfortunately, last time I checked, the ELDK toolchains did not support
> the --sysroot option, which is mandatory to use a given toolchain as an
> external toolchain in Buildroot. We have tried to support non
> sysroot-capable toolchains, but it was the source of various issues,
> and since sysroot is now quite ancient and available in most
> toolchains, it sounded like a reasonable tradeoff.

Ok, I had a look at ELDK, and unfortunately, it cannot work. I will
updated the documentation accordingly, but here is the diff of what I
will push into the documentation:

+    <p>We do not support toolchains from
+    the <a href="http://www.denx.de/wiki/DULG/ELDK">ELDK of Denx</a>,
+    for two reasons:</p>
+
+    <ul>
+
+      <li>The ELDK does not contain a pure toolchain (i.e just the
+      compiler, binutils, the C and C++ libraries), but a toolchain
+      that comes with a very large set of pre-compiled libraries and
+      programs. Therefore, Buildroot cannot import the <i>sysroot</i>
+      of the toolchain, as it would contain hundreds of megabytes of
+      pre-compiled libraries that are normally built by
+      Buildroot.</li>
+
+      <li>The ELDK toolchains have a completely non-standard custom
+      mechanism to handle multiple library variants. Instead of using
+      the standard GCC <i>multilib</i> mechanism, the ARM ELDK uses
+      different symbolic links to the compiler to differentiate
+      between library variants (for ARM soft-float and ARM VFP), and
+      the PowerPC ELDK compiler uses a <code>CROSS_COMPILE</code>
+      environment variable. This non-standard behaviour makes it
+      difficult to support ELDK in Buildroot.</li>
+
+    </ul>

Regards,

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