build: build xz from a submodule

We also install xz to the build directory, for a cleaner setup.

Author: guyush1

.gitmodules

@@ -12,3 +12,6 @@
 [submodule "src/submodule_packages/libexpat"]
 	path = src/submodule_packages/libexpat
 	url = git@github.com:guyush1/libexpat.git
+[submodule "xz"]
+	path = src/submodule_packages/xz
+	url = https://github.com/tukaani-project/xz.git

Dockerfile

@@ -1,6 +1,7 @@
 FROM ubuntu:24.04
 
 RUN apt update && apt install -y \
+    autopoint \
     binutils-multiarch \
     bison \
     file \
@@ -24,7 +25,6 @@ RUN apt update && apt install -y \
     patch \
     pkg-config \
     python3.12 \
-    python3-pip \
     python3-requests \
     libpython3-dev \
     texinfo \

src/compilation/build.sh

@@ -154,7 +154,7 @@ function build_lzma() {
     echo "$lzma_build_dir"
     mkdir -p "$lzma_build_dir"
 
-    if [[ -f "$lzma_build_dir/usr/local/lib/liblzma.a" ]]; then
+    if [[ -f "$lzma_build_dir/lib/liblzma.a" ]]; then
         >&2 echo "Skipping build: lzma already built for $target_arch"
         return 0
     fi
@@ -163,8 +163,16 @@ function build_lzma() {
 
     >&2 fancy_title "Building liblzma for $target_arch"
 
+    # Make sure configure exists by running autogen.sh
+    (
+        cd .. && ./autogen.sh 1>&2
+    )
+
+    # lzma's autoconf contains a bug, it's instal prefix is relative
+    # to the current build directory.
+    # Hence, we set the prefix here to "/" instead of realpath . .
     ../configure --enable-static "CC=$CC" "CXX=$CXX" "--host=$HOST" \
-        "CFLAGS=$CFLAGS" "CXXFLAGS=$CXXFLAGS" 1>&2
+        "CFLAGS=$CFLAGS" "CXXFLAGS=$CXXFLAGS" --prefix="/" 1>&2
     if [[ $? -ne 0 ]]; then
         return 1
     fi
@@ -697,7 +705,7 @@ function build_gdb_with_dependencies() {
 
     build_and_install_gdb "$packages_dir/binutils-gdb" \
                           "$iconv_build_dir" \
-                          "$lzma_build_dir/usr/local/" \
+                          "$lzma_build_dir" \
                           "$gmp_build_dir" \
                           "$mpfr_build_dir" \
                           "$with_python" \

src/compilation/download_packages.sh

@@ -10,7 +10,6 @@ SOURCE_URLS=(
     "https://ftp.gnu.org/pub/gnu/gmp/gmp-6.3.0.tar.xz"
     "https://ftp.gnu.org/pub/gnu/mpfr/mpfr-4.2.1.tar.xz"
     "https://ftp.gnu.org/pub/gnu/ncurses/ncurses-6.5.tar.gz"
-    "https://github.com/tukaani-project/xz/releases/download/v5.8.1/xz-5.8.1.tar.xz"
 )
 
 function unpack_tarball() {