Part 5: Cross-Compiling Temporary Tools

Overview

Now that you have a cross-compiler, you'll build temporary tools needed for the final system. These are cross-compiled using the toolchain from Part 4.

Prerequisites

Completed Part 4 (cross-toolchain)
Still logged in as lfs user
Working directory: $LFS/sources

Packages to Build (Chapter 6)

19 essential utilities that will be rebuilt later in the final system:

M4-1.4.20
Ncurses-6.5
Bash-5.3
Coreutils-9.7
Diffutils-3.12
File-5.46
Findutils-4.10.0
Gawk-5.3.2
Grep-3.12
Gzip-1.14
Make-4.4.1
Patch-2.8
Sed-4.9
Tar-1.35
Xz-5.8.1
Binutils-2.45 (Pass 2)
GCC-15.2.0 (Pass 2)

Standard Build Pattern

Most packages follow this pattern:

cd $LFS/sources
tar -xf <package>.tar.xz
cd <package>

# Configure
./configure --prefix=/usr \
            --host=$LFS_TGT \
            --build=$(./config.guess)

# Build
make

# Install
make DESTDIR=$LFS install

# Cleanup
cd $LFS/sources
rm -rf <package>

1. M4-1.4.20

Purpose: Macro processor (needed for Bison)

cd $LFS/sources
tar -xf m4-1.4.20.tar.xz
cd m4-1.4.20

./configure --prefix=/usr \
            --host=$LFS_TGT \
            --build=$(build-aux/config.guess)

make
make DESTDIR=$LFS install

cd $LFS/sources
rm -rf m4-1.4.20

2. Ncurses-6.5

Purpose: Terminal handling library

cd $LFS/sources
tar -xf ncurses-6.5-20250809.tgz
cd ncurses-6.5-20250809

# Ensure gawk is found first
sed -i s/mawk// configure

# Build tic program
mkdir build
pushd build
  ../configure
  make -C include
  make -C progs tic
popd

./configure --prefix=/usr \
            --host=$LFS_TGT \
            --build=$(./config.guess) \
            --mandir=/usr/share/man \
            --with-manpage-format=normal \
            --with-shared \
            --without-normal \
            --with-cxx-shared \
            --without-debug \
            --without-ada \
            --disable-stripping

make

make DESTDIR=$LFS TIC_PATH=$(pwd)/build/progs/tic install
ln -sv libncursesw.so $LFS/usr/lib/libncurses.so
sed -e 's/^#if.*XOPEN.*$/#if 1/' \
    -i $LFS/usr/include/curses.h

cd $LFS/sources
rm -rf ncurses-6.5-20250809

3. Bash-5.3

Purpose: Bourne-Again SHell

cd $LFS/sources
tar -xf bash-5.3.tar.gz
cd bash-5.3

./configure --prefix=/usr \
            --build=$(sh support/config.guess) \
            --host=$LFS_TGT \
            --without-bash-malloc \
            bash_cv_strtold_broken=no

make
make DESTDIR=$LFS install

# Create sh symlink
ln -sv bash $LFS/bin/sh

cd $LFS/sources
rm -rf bash-5.3

4. Coreutils-9.7

Purpose: Core utilities (ls, cp, mv, etc.)

cd $LFS/sources
tar -xf coreutils-9.7.tar.xz
cd coreutils-9.7

./configure --prefix=/usr \
            --host=$LFS_TGT \
            --build=$(build-aux/config.guess) \
            --enable-install-program=hostname \
            --enable-no-install-program=kill,uptime

make
make DESTDIR=$LFS install

# Move programs to correct location
mv -v $LFS/usr/bin/chroot $LFS/usr/sbin
mkdir -pv $LFS/usr/share/man/man8
mv -v $LFS/usr/share/man/man1/chroot.1 $LFS/usr/share/man/man8/chroot.8
sed -i 's/"1"/"8"/' $LFS/usr/share/man/man8/chroot.8

cd $LFS/sources
rm -rf coreutils-9.7

5. Diffutils-3.12

Purpose: File comparison utilities

cd $LFS/sources
tar -xf diffutils-3.12.tar.xz
cd diffutils-3.12

./configure --prefix=/usr \
            --host=$LFS_TGT \
            --build=$(./build-aux/config.guess)

make
make DESTDIR=$LFS install

cd $LFS/sources
rm -rf diffutils-3.12

6. File-5.46

Purpose: File type identification

cd $LFS/sources
tar -xf file-5.46.tar.gz
cd file-5.46

# Build on host for cross-compile
mkdir build
pushd build
  ../configure --disable-bzlib \
               --disable-libseccomp \
               --disable-xzlib \
               --disable-zlib
  make
popd

./configure --prefix=/usr --host=$LFS_TGT --build=$(./config.guess)

make FILE_COMPILE=$(pwd)/build/src/file
make DESTDIR=$LFS install

# Remove libtool archive
rm -v $LFS/usr/lib/libmagic.la

cd $LFS/sources
rm -rf file-5.46

7. Findutils-4.10.0

Purpose: File search utilities

cd $LFS/sources
tar -xf findutils-4.10.0.tar.xz
cd findutils-4.10.0

./configure --prefix=/usr \
            --localstatedir=/var/lib/locate \
            --host=$LFS_TGT \
            --build=$(build-aux/config.guess)

make
make DESTDIR=$LFS install

cd $LFS/sources
rm -rf findutils-4.10.0

8. Gawk-5.3.2

Purpose: GNU AWK text processing

cd $LFS/sources
tar -xf gawk-5.3.2.tar.xz
cd gawk-5.3.2

# Ensure build doesn't look for installed gawk
sed -i 's/extras//' Makefile.in

./configure --prefix=/usr \
            --host=$LFS_TGT \
            --build=$(build-aux/config.guess)

make
make DESTDIR=$LFS install

cd $LFS/sources
rm -rf gawk-5.3.2

9. Grep-3.12

Purpose: Pattern matching utility

cd $LFS/sources
tar -xf grep-3.12.tar.xz
cd grep-3.12

./configure --prefix=/usr \
            --host=$LFS_TGT \
            --build=$(./build-aux/config.guess)

make
make DESTDIR=$LFS install

cd $LFS/sources
rm -rf grep-3.12

10. Gzip-1.14

Purpose: File compression

cd $LFS/sources
tar -xf gzip-1.14.tar.xz
cd gzip-1.14

./configure --prefix=/usr --host=$LFS_TGT

make
make DESTDIR=$LFS install

cd $LFS/sources
rm -rf gzip-1.14

11. Make-4.4.1

Purpose: Build automation

cd $LFS/sources
tar -xf make-4.4.1.tar.gz
cd make-4.4.1

./configure --prefix=/usr \
            --without-guile \
            --host=$LFS_TGT \
            --build=$(build-aux/config.guess)

make
make DESTDIR=$LFS install

cd $LFS/sources
rm -rf make-4.4.1

12. Patch-2.8

Purpose: Apply diff patches

cd $LFS/sources
tar -xf patch-2.8.tar.xz
cd patch-2.8

./configure --prefix=/usr \
            --host=$LFS_TGT \
            --build=$(build-aux/config.guess)

make
make DESTDIR=$LFS install

cd $LFS/sources
rm -rf patch-2.8

13. Sed-4.9

Purpose: Stream editor

cd $LFS/sources
tar -xf sed-4.9.tar.xz
cd sed-4.9

./configure --prefix=/usr \
            --host=$LFS_TGT \
            --build=$(./build-aux/config.guess)

make
make DESTDIR=$LFS install

cd $LFS/sources
rm -rf sed-4.9

14. Tar-1.35

Purpose: Archive utility

cd $LFS/sources
tar -xf tar-1.35.tar.xz
cd tar-1.35

./configure --prefix=/usr \
            --host=$LFS_TGT \
            --build=$(build-aux/config.guess)

make
make DESTDIR=$LFS install

cd $LFS/sources
rm -rf tar-1.35

15. Xz-5.8.1

Purpose: XZ compression

cd $LFS/sources
tar -xf xz-5.8.1.tar.xz
cd xz-5.8.1

./configure --prefix=/usr \
            --host=$LFS_TGT \
            --build=$(build-aux/config.guess) \
            --disable-static \
            --docdir=/usr/share/doc/xz-5.8.1

make
make DESTDIR=$LFS install

# Remove libtool archives
rm -v $LFS/usr/lib/liblzma.la

cd $LFS/sources
rm -rf xz-5.8.1

16. Binutils-2.45 - Pass 2

Purpose: Final cross-compile of binutils

cd $LFS/sources
tar -xf binutils-2.45.tar.xz
cd binutils-2.45

# Apply sed for library path
sed '6009s/$add_dir//' -i ltmain.sh

mkdir -v build
cd build

../configure \
    --prefix=/usr \
    --build=$(../config.guess) \
    --host=$LFS_TGT \
    --disable-nls \
    --enable-shared \
    --enable-gprofng=no \
    --disable-werror \
    --enable-64-bit-bfd \
    --enable-new-dtags \
    --enable-default-hash-style=gnu

make
make DESTDIR=$LFS install

# Remove libtool archives
rm -v $LFS/usr/lib/lib{bfd,ctf,ctf-nobfd,opcodes,sframe}.la

cd $LFS/sources
rm -rf binutils-2.45

17. GCC-15.2.0 - Pass 2

Purpose: Final cross-compiler

Build Time: ~11 SBU Disk Space: ~4.9 GB

cd $LFS/sources
tar -xf gcc-15.2.0.tar.xz
cd gcc-15.2.0

# Extract prerequisites
tar -xf ../mpfr-4.2.2.tar.xz
mv -v mpfr-4.2.2 mpfr
tar -xf ../gmp-6.3.0.tar.xz
mv -v gmp-6.3.0 gmp
tar -xf ../mpc-1.3.1.tar.gz
mv -v mpc-1.3.1 mpc

# Fix library path for x86_64
case $(uname -m) in
  x86_64)
    sed -e '/m64=/s/lib64/lib/' \
        -i.orig gcc/config/i386/t-linux64
  ;;
esac

# Fix directory structure
sed '/thread_header =/s/@.*@/gthr-posix.h/' \
    -i libgcc/Makefile.in libstdc++-v3/include/Makefile.in

mkdir -v build
cd build

../configure \
    --build=$(../config.guess) \
    --host=$LFS_TGT \
    --target=$LFS_TGT \
    LDFLAGS_FOR_TARGET=-L$PWD/$LFS_TGT/libgcc \
    --prefix=/usr \
    --with-build-sysroot=$LFS \
    --enable-default-pie \
    --enable-default-ssp \
    --disable-nls \
    --disable-multilib \
    --disable-libatomic \
    --disable-libgomp \
    --disable-libquadmath \
    --disable-libsanitizer \
    --disable-libssp \
    --disable-libvtv \
    --enable-languages=c,c++

make
make DESTDIR=$LFS install

# Create utility symlink
ln -sv gcc $LFS/usr/bin/cc

cd $LFS/sources
rm -rf gcc-15.2.0

Verification

Test the toolchain:

# Create test program
echo 'int main(){}' | $LFS_TGT-gcc -xc -
readelf -l a.out | grep ld-linux

# Should show:
# [Requesting program interpreter: /lib64/ld-linux-x86-64.so.2]

rm a.out

Next Steps

Temporary tools complete! Proceed to:

Part 6: Enter chroot and build additional tools
Part 7: Build final system in chroot

Important Notes

Build packages in the order listed
Don't skip any packages
Clean up after each build to save space
Total build time: ~15-20 SBUs

Part 05 Temporary Tools