2.1. The Unified Source Tree

2.1.1. Incorporating Newlib within the Tool Chain Build

The three separate packages, binutils, GCC and GDB are all taken from a common source tree. GCC and GDB both use many libraries from binutils. It is convenient to reassemble that source tree and make a single build of all the tools together.

The easiest way to achieve this is to link all the top level directories in each package into a single unified directory, leaving out any duplicated files or directories.

The following bash script will take unpacked distributions of binutils GCC and GDB and link them into a single directory, srcw.

#!/bin/bash

component_dirs='binutils-2.18.50 gcc-4.2.2 gdb-6.8'
unified_src=srcw

cd ${unified_src}
ignore_list=". .. CVS .svn"
    
for srcdir in ${component_dirs}
do
    echo "Component: $srcdir"
    case srcdir
        in
        /* | [A-Za-z]:[\\/]*)
            ;;
            
        *)
            srcdir="../${srcdir}"
            ;;
    esac
        
    files=`ls -a ${srcdir}`
        
    for f in ${files}
    do
        found=
            
        for i in ${ignore_list}
        do
            if [ "$f" = "$i" ]
            then
                found=yes
            fi
        done
            
        if [ -z "${found}" ]
        then
            echo "$f            ..linked"
            ln -s ${srcdir}/$f .
        fi
    done

    ignore_list="${ignore_list} ${files}"
done

cd ..

The entire tool chain can then be configured and built in a separate directory. The configure script understands to pass on top level arguments to subsidiary configuration scripts. For example to configure to build a C only tool chain for the 32-bit OpenRISC 1000 architecture to be installed in /opt/or32-elf, the following would be appropriate.

mkdir build
cd build
../src/configure --target=or32-elf --enable-languages=c --prefix=/opt/or32-elf
cd ..

Each tool can be built with its own specific target within that build directory

cd build
make all-build all-binutils all-gas all-ld all-gcc all-gdb
cd ..

	Note
	The initial make target, `all-build` is used to build some of the baseline libraries and tools used throughout the tool chain.

Similarly the tools can be installed using the following:

cd build
make install-build install-binutils install-gas install-ld install-gcc \
     install-gdb
cd ..