Setting up a cross-compilation environment for a specific target platform

Question

I'd like to set up a cross-compilation environment on a Ubuntu 9.10 box. From the documents I've read so far (these ones, for example) this involves compiling the toolchain of the target platforms.

My question is: how do you determine the required version of each of the packages in the toolchain for a specific target platform? Is there any rule of thumb I can follow?

This is a list found in one of the websites linked above:

binutils-2.16.1.tar.bz2
linux-2.6.20.1.tar.bz2
glibc-2.5.tar.bz2
glibc-linuxthreads-2.5.tar.bz2
gcc-core-4.2.0.tar.bz2
gcc-g++-4.2.0.tar.bz2

But suppose I want to generate executables for standard Ubuntu 8.04 and CentOS 5.3 boxes. What are the necessary packages?

My primary need is to avoid errors like "/usr/lib/libstdc++.so.6: version `GLIBCXX_3.4.11' not found" in the customers' machines but in the future I want to deal with different architectures as well.

Answer 1

It is generally a good idea to build a cross-toolchain that uses the same version of libc (and other libraries) found on the target system. This is especially important in the case of libraries that use versioned symbols or you could wind up with errors like "/usr/lib/libstdc++.so.6: version 'GLIBCXX_3.4.11' not found".

Same Architecture

For generating executables for standard Ubuntu 8.04 and CentOS 5.3 systems, you could install the distributions in virtual machines and do the necessary compilation from within the virtual machine to guarantee the resulting binaries are compatible with the library versions from each distribution.

Another option would be to setup chroot build environments instead of virtual machines for the target distributions.

You could also build toolchains targeted at different environments (different library versions) and build under your Ubuntu 9.10 environment without using virtual machines or chroot environments. I have used Dan Kegel's crosstool for creating such cross-toolchains.

Different Architecture

As I noted in my answer to a another cross-compiler question, I used Dan Kegel's crosstool for creating my arm cross-toolchain.

It appears it may be slightly out of date, but there is a matrix of build results for various architectures to help determine a suitable combination of gcc, glibc, binutils, and linux kernel headers.

Required Package Versions

In my experience, there really isn't a rule of thumb. Not all combinations of gcc, binutils, glibc, and linux headers will build successfully. Even if the build completes, some level of testing is necessary to validate the build's success. This is sometimes done by compiling the Linux kernel with your new cross-toolchain. Depending on the target system and architecture, some patching of the source may be necessary to produce a successful build.

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Since you are setting up this cross-compilation environment on Ubuntu 9.10, you might want to look into the dpkg-cross package.