7. Installing the GNU CC compilers

You need to restart your system back into the normal Linux system to compile the gcc compilers. Before you reboot, unmount the partitions you mounted (that contained the glibc sources) and mount the LFS root partition read only by running mount -o remount,ro / /

7.1 Installing GCC 2.95.2

The GCC Installation notes recommend a separate directory for the object files. This means you have a directory where the gcc sources reside in and a different directory where compiled files are being created. Say you unpacked the gcc archive in /usr/src/gcc-2.95.2 , you could make a directory called /usr/src/gcc-install

• Unpack the GCC archive
• Go to the gcc-install directory
• Configure the package by running ../gcc-2.95.2/configure --prefix=/usr --enable-shared
• Compile the package by running make bootstrap
• Create a file $LFS/root/test.c containing the following

// Begin test.c
#include <stdio.h>
int main() {
   printf("Hello World!\n");
   return 0;
}
// End test.c

• Create a file $LFS/root/test2.c containing the following:

// Begin test2.c
#include <iostream.h>
int main() {
   cout << "Hello World!" << endl;
   return 0;
}
// End test2.c

• Reboot the computer into the LFS system
• Remount the LFS partition in read-write mode
• Mount the partition that contains the gcc-2.95.2 and gcc-install directories
• Create a symlink that links /usr/src/gcc-2.95.2 to the usr/src/gcc-2.95.2 directory that contains the gcc source files.
• Go to the gcc-install directory
• Install the package by running make install
• Go to the /root directory
• Compile+link test.c by running gcc test.c -o test
• Compile+link test2.c by running g++ test2.c -o test2
• Run both programs
• If both programs run without errors or crashing than the compilers and linkers seem to be working
• Remove the /usr/src/gcc-2.95.2 symlink

7.2 Installing GCC 2.7.2.3

• Unpack the gcc-2.7.2.3 archive
• Configure the package by running configure --prefix=/usr/gcc2723 --enable-shared --local-prefix=/usr/gcc2723
• If the configure script says it can't determine the system type, then configure the package by running configure --host=<cpu>-linux-gnu --prefix=/usr/gcc2723 --enable-shared --local-prefix=/usr/gcc2723

Enter the right value for <cpu>. If you have a Pentium, enter i586. If you have a PII or higher, enter i686. If you don't have an Intel based platform than you have to figure out yourself what to enter since the only experience I have are with Intel based platforms (sorry, but I just don't have the money to buy myself an alpha, SPARC or whatever system ;)

• Build the compiler by executing these commands in sequence:

make LANGUAGES=c
make stage1 (ignore errors about files not found)
make CC="stage1/xgcc -Bstage1/" CFLAGS="-g -O2"
make stage2
make CC="stage2/xgcc -Bstage2/" CFLAGS="-g -O2"
make compare

• If make compare doesn't report any differences, the compiler is build successfully.
• Install the package by running make install CC="stage2/xgcc -Bstage2/" CFLAGS="-g -O2"