Previous Home Next

6.11. zlib-ng 2.3.3

zlib-ng provides zlib-compatible compression and decompression libraries for the target system.

Input assumption: zlib-ng-2.3.3.tar.gz is already present in LBI_SOURCES from the chapter 4 source staging step.

Licenses:

zlib License

Dependencies:

musl (libc)
cmake
ninja

zlib-ng is a deflate compression library with a zlib-compatible API mode. we need it to provide libz for packages in later chapters that depend on zlib-compatible compression support.

Extract and Enter the Source Tree

cd "$LBI_SOURCES"
tar -xf zlib-ng-2.3.3.tar.gz
cd zlib-ng-2.3.3

Configure zlib-ng

lbi_cmake build \
    -DCMAKE_C_COMPILER="$LBI_ROOT/system/tools/bin/$LBI_TARGET-clang" \
    -DCMAKE_AR="$LBI_ROOT/system/tools/bin/$LBI_TARGET-ar" \
    -DCMAKE_RANLIB="$LBI_ROOT/system/tools/bin/$LBI_TARGET-ranlib" \
    -DCMAKE_C_FLAGS="--target=$LBI_TARGET --sysroot=$LBI_ROOT $LWI_CFLAGS" \
    -DCMAKE_SHARED_LINKER_FLAGS="--target=$LBI_TARGET --sysroot=$LBI_ROOT $LBI_CUSTOM_LDFLAGS" \
    -DCMAKE_EXE_LINKER_FLAGS="--target=$LBI_TARGET --sysroot=$LBI_ROOT $LBI_CUSTOM_LDFLAGS" \
    -DZLIB_COMPAT=ON \
    -DBUILD_TESTING=OFF \
    -DINSTALL_UTILS=OFF

Build zlib-ng

cmake --build build $LWI_MAKE_FLAGS

Install zlib-ng

DESTDIR="$LBI_ROOT" cmake --install build

Command Explanations

lbi_cmake build: Configures zlib-ng with the book's CMake helper and writes generated files into the build directory.
-DCMAKE_C_COMPILER="$LBI_ROOT/system/tools/bin/$LBI_TARGET-clang": Uses the target-prefixed Clang compiler.
-DCMAKE_AR and -DCMAKE_RANLIB: Use the matching target-prefixed archive tools.
-DCMAKE_C_FLAGS="--target=$LBI_TARGET --sysroot=$LBI_ROOT $LWI_CFLAGS": Targets the selected triple and sysroot while preserving local C flag tuning.
-DCMAKE_SHARED_LINKER_FLAGS and -DCMAKE_EXE_LINKER_FLAGS: Keep shared-library and executable link steps pointed at the target sysroot.
-DZLIB_COMPAT=ON: Builds zlib-ng in zlib-compatible API and library-name mode.
-DBUILD_TESTING=OFF: Skips test programs that are not needed for the target bootstrap.
-DINSTALL_UTILS=OFF: Installs the library and headers without zlib-ng's optional command-line utilities.
cmake --build build $LWI_MAKE_FLAGS: Builds the configured tree using the shared parallel build setting.
DESTDIR="$LBI_ROOT" cmake --install build: Installs into the target root instead of the host filesystem.

Previous Home Next