Toolchain: Add LLVM patch and script for building it

This contains all the bits and pieces necessary to build a Clang binary that will correctly compile SerenityOS. I had some trouble with getting LLVM building with a single command, so for now, I decided to build each LLVM component in a separate command invocation. In the future, we can also make the main llvm build step architecture-independent, but that would come with extra work to make library and include paths work. The binutils build invocation and related boilerplate is duplicated because we only use `objdump` from GNU binutils in the Clang toolchain, so most features can be disabled.
2025-07-26 17:17:35 +00:00 · 2021-07-31 15:54:48 +02:00 · 2021-07-31 15:54:48 +02:00 · 15e217ea68
commit 15e217ea68
parent 5d617be462
4 changed files with 1299 additions and 1 deletions
--- a/Toolchain/BuildClang.sh
+++ b/Toolchain/BuildClang.sh
@ -0,0 +1,353 @@
+#!/usr/bin/env bash
+set -eo pipefail
+
+# === CONFIGURATION AND SETUP ===
+
+DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"
+
+echo "$DIR"
+
+ARCH=${ARCH:-"i686"}
+LLVM_ARCH=
+[ "$ARCH" = "i686" ] && LLVM_ARCH="i386" || LLVM_ARCH="$ARCH"
+LLVM_TARGET="$LLVM_ARCH-pc-serenity"
+PREFIX="$DIR/Local/clang/$ARCH"
+BUILD="$DIR/../Build/$ARCH"
+SYSROOT="$BUILD/Root"
+
+MD5SUM="md5sum"
+REALPATH="realpath"
+MAKE="make"
+NPROC="nproc"
+
+SYSTEM_NAME="$(uname -s)"
+
+if [ "$SYSTEM_NAME" = "OpenBSD" ]; then
+    MD5SUM="md5 -q"
+    REALPATH="readlink -f"
+    MAKE="gmake"
+    NPROC="sysctl -n hw.ncpuonline"
+    export CC=egcc
+    export CXX=eg++
+    export LDFLAGS=-Wl,-z,notext
+elif [ "$SYSTEM_NAME" = "FreeBSD" ]; then
+    MD5SUM="md5 -q"
+    MAKE="gmake"
+    NPROC="sysctl -n hw.ncpu"
+fi
+
+if [ -z "$MAKEJOBS" ]; then
+    MAKEJOBS=$($NPROC)
+fi
+
+
+if [ ! -d "$BUILD" ]; then
+    mkdir -p "$BUILD"
+fi
+BUILD=$($REALPATH "$BUILD")
+
+dev=
+while [ "$1" != "" ]; do
+    case $1 in
+        --dev )           dev=1
+                          ;;
+    esac
+    shift
+done
+
+echo PREFIX is "$PREFIX"
+echo SYSROOT is "$SYSROOT"
+
+mkdir -p "$DIR/Tarballs"
+
+LLVM_VERSION="12.0.1"
+LLVM_MD5SUM="c28061313a4f1b7d74cd491a19f569b4"
+LLVM_NAME="llvm-project-$LLVM_VERSION.src"
+LLVM_PKG="$LLVM_NAME.tar.xz"
+LLVM_URL="https://github.com/llvm/llvm-project/releases/download/llvmorg-$LLVM_VERSION/$LLVM_PKG"
+
+# We need GNU binutils because we use a feature that llvm-objdump doesn't support yet.
+BINUTILS_VERSION="2.37"
+BINUTILS_MD5SUM="1e55743d73c100b7a0d67ffb32398cdb"
+BINUTILS_NAME="binutils-$BINUTILS_VERSION"
+BINUTILS_PKG="${BINUTILS_NAME}.tar.gz"
+BINUTILS_BASE_URL="https://ftp.gnu.org/gnu/binutils"
+
+buildstep() {
+    NAME=$1
+    shift
+    "$@" 2>&1 | sed $'s|^|\x1b[34m['"${NAME}"$']\x1b[39m |'
+}
+
+# === DEPENDENCIES ===
+buildstep dependencies echo "Checking whether 'make' is available..."
+if ! command -v ${MAKE:-make} >/dev/null; then
+    buildstep dependencies echo "Please make sure to install GNU Make (for the '${MAKE:-make}' tool)."
+    exit 1
+fi
+
+buildstep dependencies echo "Checking whether CMake is available..."
+if ! command -v cmake >/dev/null; then
+    buildstep dependencies echo "Please make sure to install CMake."
+    exit 1
+fi
+
+buildstep dependencies echo "Checking whether 'patch' is available..."
+if ! command -v patch >/dev/null; then
+    buildstep dependencies echo "Please make sure to install GNU patch."
+fi
+
+buildstep dependencies echo "Checking whether your C compiler works..."
+if ! ${CC:-cc} -o /dev/null -xc - >/dev/null <<'PROGRAM'
+int main() {}
+PROGRAM
+then
+    buildstep dependencies echo "Please make sure to install a working C compiler."
+    exit 1
+fi
+
+buildstep dependencies echo "Checking whether your C++ compiler works..."
+if ! ${CXX:-c++} -o /dev/null -xc - >/dev/null <<'PROGRAM'
+int main() {}
+PROGRAM
+then
+    buildstep dependencies echo "Please make sure to install a working C++ compiler."
+    exit 1
+fi
+
+# === DOWNLOAD AND PATCH ===
+
+pushd "$DIR/Tarballs"
+    md5=""
+    if [ -e "$LLVM_PKG" ]; then
+        md5="$($MD5SUM ${LLVM_PKG} | cut -f1 -d' ')"
+        echo "llvm md5='$md5'"
+    fi
+
+    if [ "$md5" != "$LLVM_MD5SUM" ] ; then
+        rm -f "$LLVM_PKG"
+        curl -LO "$LLVM_URL"
+    else
+        echo "Skipped downloading LLVM"
+    fi
+
+    if [ -d "$LLVM_NAME" ]; then
+        # Drop the previously patched extracted dir
+        rm -rf "${LLVM_NAME}"
+        # Also drop the build dir
+        rm -rf "$DIR/Build/clang/$ARCH"
+    fi
+    echo "Extracting LLVM..."
+    tar -xJf "$LLVM_PKG"
+
+    pushd "$LLVM_NAME"
+        if [ "$dev" = "1" ]; then
+            git init > /dev/null
+            git add . > /dev/null
+            git commit -am "BASE" > /dev/null
+            git apply "$DIR"/Patches/llvm.patch > /dev/null
+        else
+            patch -p1 < "$DIR/Patches/llvm.patch" > /dev/null
+        fi
+        $MD5SUM "$DIR/Patches/llvm.patch" > .patch.applied
+    popd
+
+    md5=""
+    if [ -e "$BINUTILS_PKG" ]; then
+        md5="$($MD5SUM $BINUTILS_PKG | cut -f1 -d' ')"
+        echo "bu md5='$md5'"
+    fi
+
+    if [ "$md5" != "$BINUTILS_MD5SUM" ]; then
+        rm -f "$BINUTILS_PKG"
+        curl -LO "$BINUTILS_BASE_URL/$BINUTILS_PKG"
+    else
+        echo "Skipped downloading GNU binutils"
+    fi
+
+    if [ -d "$BINUTILS_NAME" ]; then
+        rm -rf "$BINUTILS_NAME"
+        rm -rf "$DIR/Build/clang/$ARCH/binutils"
+    fi
+    echo "Extracting GNU binutils"
+
+
+    tar -xzf "$BINUTILS_PKG"
+    pushd "$BINUTILS_NAME"
+        if [ "$dev" = "1" ]; then
+            git init > /dev/null
+            git add . > /dev/null
+            git commit -am "BASE" > /dev/null
+            git apply "$DIR"/Patches/binutils.patch > /dev/null
+        else
+            patch -p1 < "$DIR/Patches/binutils.patch" > /dev/null
+        fi
+         $MD5SUM "$DIR/Patches/binutils.patch" > .patch.applied
+    popd
+popd
+
+# === COPY SERENITYOS HEADERS ===
+
+mkdir -p "$BUILD"
+pushd "$BUILD"
+    mkdir -p Root/usr/include/
+    SRC_ROOT=$($REALPATH "$DIR"/..)
+    FILES=$(find "$SRC_ROOT"/Userland/Libraries/LibC "$SRC_ROOT"/Userland/Libraries/LibM "$SRC_ROOT"/Userland/Libraries/LibPthread "$SRC_ROOT"/Userland/Libraries/LibDl -name '*.h' -print)
+    for header in $FILES; do
+        target=$(echo "$header" | sed -e "s@$SRC_ROOT/Userland/Libraries/LibC@@" -e "s@$SRC_ROOT/Userland/Libraries/LibM@@" -e "s@$SRC_ROOT/Userland/Libraries/LibPthread@@" -e "s@$SRC_ROOT/Userland/Libraries/LibDl@@")
+        buildstep "system_headers" install -D "$header" "Root/usr/include/$target"
+    done
+    unset SRC_ROOT
+popd
+
+# === COMPILE AND INSTALL ===
+
+rm -rf "$PREFIX"
+mkdir -p "$PREFIX"
+
+mkdir -p "$DIR/Build/clang/$ARCH"
+
+pushd "$DIR/Build/clang/$ARCH"
+
+    mkdir -p llvm
+    pushd llvm
+        buildstep "llvm+clang/configure" cmake "$DIR/Tarballs/llvm-project-$LLVM_VERSION.src/llvm" \
+            -G Ninja \
+            -DCMAKE_BUILD_TYPE="MinSizeRel" \
+            -DCMAKE_INSTALL_PREFIX="$PREFIX" \
+            -DLLVM_DEFAULT_TARGET_TRIPLE="$LLVM_TARGET" \
+            -DLLVM_TARGETS_TO_BUILD=X86 \
+            -DLLVM_ENABLE_BINDINGS=OFF \
+            -DLLVM_ENABLE_PER_TARGET_RUNTIME_DIR=OFF \
+            -DLLVM_ENABLE_PROJECTS="clang;lld" \
+            -DLLVM_INCLUDE_BENCHMARKS=OFF \
+            -DLLVM_INCLUDE_TESTS=OFF \
+            ${dev:+"-DLLVM_CCACHE_BUILD=ON"} || exit 1
+
+        buildstep "llvm+clang/build" ninja -j "$MAKEJOBS" || exit 1
+        buildstep "llvm+clang/install" ninja install || exit 1
+    popd
+
+    LLVM_COMPILER_FLAGS="-target $LLVM_TARGET --sysroot $SYSROOT -ftls-model=initial-exec -ffreestanding -nostdlib -nostdlib++"
+
+    mkdir -p "compiler-rt"
+    pushd compiler-rt
+        buildstep "compiler-rt/configure" cmake "$DIR/Tarballs/llvm-project-$LLVM_VERSION.src/compiler-rt" \
+            -GNinja \
+            -DCMAKE_SYSROOT="$SYSROOT" \
+            -DCMAKE_INSTALL_PREFIX="$PREFIX/lib/clang/${LLVM_VERSION}" \
+            -DCMAKE_BUILD_TYPE="Release" \
+            -DCMAKE_AR="$PREFIX/bin/llvm-ar" \
+            -DCMAKE_C_COMPILER="$PREFIX/bin/clang" \
+            -DCMAKE_C_COMPILER_TARGET="$LLVM_TARGET" \
+            -DCMAKE_C_FLAGS="$LLVM_COMPILER_FLAGS" \
+            -DCMAKE_CXX_COMPILER="$PREFIX/bin/clang++" \
+            -DCMAKE_CXX_FLAGS="$LLVM_COMPILER_FLAGS" \
+            -DCMAKE_CXX_COMPILER_TARGET="$LLVM_TARGET" \
+            -DCMAKE_ASM_COMPILER="$PREFIX/bin/clang" \
+            -DCMAKE_ASM_COMPILER_TARGET="$LLVM_TARGET" \
+            -DCMAKE_ASM_FLAGS="$LLVM_COMPILER_FLAGS" \
+            -DLLVM_CONFIG_PATH="$PREFIX/bin/llvm-config" \
+            -DCOMPILER_RT_EXCLUDE_ATOMIC_BUILTIN=OFF \
+            -DCOMPILER_RT_OS_DIR="serenity" \
+            -DCOMPILER_RT_DEFAULT_TARGET_ONLY=ON \
+            -DCOMPILER_RT_BUILD_BUILTINS=ON \
+            -DCOMPILER_RT_BUILD_CRT=ON \
+            -DCOMPILER_RT_BUILD_LIBFUZZER=OFF \
+            -DCOMPILER_RT_BUILD_MEMPROF=OFF \
+            -DCOMPILER_RT_BUILD_PROFILE=OFF \
+            -DCOMPILER_RT_BUILD_SANITIZERS=OFF \
+            -DCOMPILER_RT_BUILD_XRAY=OFF || exit 1
+
+        buildstep "compiler-rt/build" ninja -j "$MAKEJOBS" || exit 1
+        buildstep "compiler-rt/install" ninja install || exit 1
+    popd
+
+    mkdir -p libunwind
+    pushd libunwind
+        buildstep "libunwind/configure" cmake "$DIR/Tarballs/llvm-project-$LLVM_VERSION.src/libunwind" \
+            -GNinja \
+            -DCMAKE_BUILD_TYPE="Release" \
+            -DCMAKE_SYSROOT="$SYSROOT" \
+            -DCMAKE_C_COMPILER="$PREFIX/bin/clang" \
+            -DCMAKE_C_COMPILER_TARGET="$LLVM_TARGET" \
+            -DCMAKE_C_FLAGS="$LLVM_COMPILER_FLAGS" \
+            -DCMAKE_CXX_COMPILER="$PREFIX/bin/clang++" \
+            -DCMAKE_CXX_COMPILER_TARGET="$LLVM_TARGET" \
+            -DCMAKE_CXX_FLAGS="$LLVM_COMPILER_FLAGS" \
+            -DCMAKE_INSTALL_PREFIX="$PREFIX" \
+            -DLLVM_CONFIG_PATH="$PREFIX/bin/llvm-config" \
+            -DLIBUNWIND_TARGET_TRIPLE="$LLVM_TARGET" \
+            -DLIBUNWIND_SYSROOT="$SYSROOT" || exit 1
+
+        buildstep "libunwind/build" ninja -j "$MAKEJOBS" || exit 1
+        buildstep "libunwind/install" ninja install || exit 1
+    popd
+
+    mkdir -p libcxxabi
+    pushd libcxxabi
+         buildstep "libcxxabi/configure" cmake "$DIR/Tarballs/llvm-project-$LLVM_VERSION.src/libcxxabi" \
+            -GNinja \
+            -DCMAKE_BUILD_TYPE="Release" \
+            -DCMAKE_SYSROOT="$SYSROOT" \
+            -DCMAKE_C_COMPILER="$PREFIX/bin/clang" \
+            -DCMAKE_C_COMPILER_TARGET="$LLVM_TARGET" \
+            -DCMAKE_C_FLAGS="$LLVM_COMPILER_FLAGS" \
+            -DCMAKE_CXX_COMPILER="$PREFIX/bin/clang++" \
+            -DCMAKE_CXX_COMPILER_TARGET="$LLVM_TARGET" \
+            -DCMAKE_CXX_FLAGS="$LLVM_COMPILER_FLAGS" \
+            -DCMAKE_INSTALL_PREFIX="$PREFIX" \
+            -DLLVM_CONFIG_PATH="$PREFIX/bin/llvm-config" \
+            -DLIBCXXABI_STANDALONE_BUILD=ON \
+            -DLIBCXXABI_ENABLE_EXCEPTIONS=ON \
+            -DLIBCXXABI_STANDALONE_BUILD=ON \
+            -DLIBCXXABI_ENABLE_ASSERTIONS=OFF \
+            -DLIBCXXABI_BAREMETAL=ON || exit 1
+
+        buildstep "libcxxabi/build" ninja -j "$MAKEJOBS" || exit 1
+        buildstep "libcxxabi/install" ninja install || exit 1
+    popd
+
+    mkdir -p libcxx
+    pushd libcxx
+        buildstep "libcxx/configure" cmake "$DIR/Tarballs/llvm-project-$LLVM_VERSION.src/libcxx" \
+            -G Ninja \
+            -DCMAKE_BUILD_TYPE="Release" \
+            -DCMAKE_BINARY_DIR="$PREFIX/usr" \
+            -DCMAKE_SYSROOT="$SYSROOT" \
+            -DCMAKE_C_COMPILER="$PREFIX/bin/clang" \
+            -DCMAKE_C_FLAGS="$LLVM_COMPILER_FLAGS" \
+            -DCMAKE_CXX_COMPILER="$PREFIX/bin/clang++" \
+            -DCMAKE_CXX_FLAGS="$LLVM_COMPILER_FLAGS" \
+            -DCMAKE_INSTALL_PREFIX="$PREFIX" \
+            -DLLVM_CONFIG_PATH="$PREFIX/bin/llvm-config" \
+            -DLLVM_BINARY_DIR="$PREFIX/usr" \
+            -DLIBCXX_INSTALL_LIBRARY=ON \
+            -DLIBCXX_ENABLE_LOCALIZATION=OFF \
+            -DLIBCXX_ENABLE_FILESYSTEM=OFF \
+            -DLIBCXX_INSTALL_HEADERS=ON \
+            -DLIBCXX_ENABLE_SHARED=ON \
+            -DLIBCXX_ENABLE_LOCALIZATION=OFF \
+            -DLIBCXX_ENABLE_STATIC=ON \
+            -DLIBCXX_CXX_ABI="libcxxabi" \
+            -DLIBCXX_INCLUDE_BENCHMARKS=OFF || exit 1
+
+        buildstep "libcxx/build" ninja -j "$MAKEJOBS" || exit 1
+        buildstep "libcxx/install" ninja install || exit 1
+        buildstep "libcxx/install-headers" ninja install-cxx-headers || exit 1
+    popd
+
+    mkdir -p binutils
+    pushd binutils
+        buildstep "binutils/configure" "$DIR/Tarballs/$BINUTILS_NAME/configure" --prefix="$PREFIX/binutils" \
+            --target="$ARCH-pc-serenity" \
+            --disable-nls \
+            --disable-gas \
+            --disable-gold \
+            --disable-ld \
+            --disable-gprof \
+            --enable-shared || exit 1
+        buildstep "binutils/build" "$MAKE" -j "$MAKEJOBS" || exit 1
+        buildstep "binutils/install" "$MAKE" install || exit 1
+    popd
+popd