Script to Build LLVM 19 on x86_64 macOS 15

build-llvm.sh

#!/bin/sh

set -e

BUILD_DIR=build-$(date +%Y-%m-%d-%I-%M-%S)
echo BUILD_DIR=${BUILD_DIR}
# BUILD_DIR=build-2024-04-19-01-09-40
mkdir ${BUILD_DIR}

LLVM_VERSION_MAJOR=19
LLVM_VERSION_MINOR=1
LLVM_VERSION_EXTRA=5
LLVM_VERSION_TO_COMPILE=${LLVM_VERSION_MAJOR}.${LLVM_VERSION_MINOR}.${LLVM_VERSION_EXTRA}

# LLVM_ROOT=$PWD/build-2024-04-19-01-09-40
LLVM_BIN="${LLVM_ROOT}/bin"
LLVM_LIB="${LLVM_ROOT}/lib"
INSTALL_PATH="/opt/llvm${LLVM_VERSION_TO_COMPILE}"
MACOS_SDK_ROOT=$(xcrun --show-sdk-path)
MACOS_VERSION=$(sw_vers -productVersion 2>&1 | perl -p -e 's/([^.]+)\.([^.]+)\..*/$1.$2/')
DARWIN_VERSION=$(uname -r)
LLVM_CLANG_C_CONFIG_FILE_NAME="x86_64-apple-darwin${DARWIN_VERSION}-clang.cfg"
LLVM_CLANG_CPP_CONFIG_FILE_NAME="x86_64-apple-darwin${DARWIN_VERSION}-clang++.cfg"

export LDFLAGS="-lc++abi -fuse-ld=lld -Wl,-rpath,${LLVM_LIB} -Wl,-rpath,${LLVM_LIB}"
if [ -d ${INSTALL_PATH}/etc ]; then
  rm -f ${INSTALL_PATH}/etc/*.cfg
fi

# it should be x86_64h-apple-darwin for haswell...
# BUT, conan doesn't supported x86_64h.  A number of
# packages don't recognize x86_64 as an architecture...
LLVM_TRIPLE=x86_64-apple-darwin

# git reset --hard llvmorg-${LLVM_VERSION_TO_COMPILE}
# git apply ~/backup/llvm.diff
#
# export PATH="${HOME}/Library/Python/3.9/bin:/opt/bin:/usr/bin:/bin"

export PATH="${LLVM_ROOT}/bin:${HOME}/Library/Python/3.9/bin:/opt/bin:/usr/bin:/bin"
# export PATH="${HOME}/Library/Python/3.9/bin:/opt/bin:/usr/bin:/bin"

# lldb/scripts/macos-setup-codesign.sh

cmake_args=(
  -DCMAKE_BUILD_TYPE:STRING=Release
  -DLLVM_ENABLE_RUNTIMES:STRING="libcxx;libcxxabi;compiler-rt;libunwind"
  -DLLVM_ENABLE_PROJECTS:STRING="clang;clang-tools-extra;lldb;lld"

  -DCMAKE_MACOSX_RPATH:BOOL=ON
  -DCMAKE_INSTALL_RPATH:FILEPATH="${INSTALL_PATH}/lib;${INSTALL_PATH}/lib/darwin"
  
  # -DCMAKE_SKIP_RPATH:BOOL=ON
  # -DLLVM_LOCAL_RPATH="${LLVM_ROOT}/lib;${LLVM_ROOT}/lib/darwin"
  # -DCMAKE_INSTALL_NAME_DIR="${INSTALL_PATH}/lib"
  
  -DDEFAULT_SYSROOT:PATH=${MACOS_SDK_ROOT}
  
  -DLLVM_RUNTIME_TARGETS:STRING="${LLVM_TRIPLE}"
  -DCMAKE_C_COMPILER_TARGET:STRING="${LLVM_TRIPLE}"
  -DCMAKE_CXX_COMPILER_TARGET:STRING="${LLVM_TRIPLE}"
  
  -DCMAKE_C_COMPILER_LAUNCHER=/opt/bin/ccache 
  -DCMAKE_CXX_COMPILER_LAUNCHER=/opt/bin/ccache

  -DLLVM_TARGETS_TO_BUILD:STRING=X86
  -DLLVM_RUNTIME_TARGETS:STRING="${LLVM_TRIPLE}"
  -DCMAKE_C_COMPILER_TARGET:STRING="${LLVM_TRIPLE}"
  -DCMAKE_CXX_COMPILER_TARGET:STRING="${LLVM_TRIPLE}"
  -DRUNTIMES_BUILD_ALLOW_DARWIN:BOOL=ON
  
  -DCMAKE_C_COMPILER:FILEPATH="${LLVM_BIN}/clang"
  -DCMAKE_CXX_COMPILER:FILEPATH="${LLVM_BIN}/clang++"
  -DCMAKE_RANLIB:FILEPATH="${LLVM_BIN}/ranlib"
  -DCMAKE_AR:FILEPATH="${LLVM_BIN}/ar"
  -DCMAKE_ASM_COMPILER:FILEPATH="${LLVM_BIN}/clang"
  -DCMAKE_LINKER:FILEPATH="${LLVM_BIN}/lld"
  -DCMAKE_NM:FILEPATH="${LLVM_BIN}/nm"
  -DCMAKE_RANLIB:FILEPATH="${LLVM_BIN}/llvm-ranlib"
  
  # -DCMAKE_EXE_LINKER_FLAGS="-lc++abi -fuse-ld=lld"
  # -DLLDB_BUILD_FRAMEWORK:BOOL=OFF
  -DLLDB_USE_SYSTEM_DEBUGSERVER:BOOL=OFF
  -DLLDB_ENABLE_LIBEDIT:BOOL=ON
  -DLLDB_ENABLE_CURSES:BOOL=ON
  -DDLLVM_ENABLE_TERMINFO:BOOL=ON
  
  
  # fails with cmake-lipo on X86_64!
  # -DCOMPILER_RT_DEFAULT_TARGET_ONLY:BOOL=ON
  -DRUNTIMES_BUILD_ALLOW_DARWIN:BOOL=ON

  -DCLANG_DEFAULT_CXX_STDLIB:STRING=libc++
  -DCLANG_DEFAULT_RTLIB:STRING=compiler-rt
  -DCLANG_DEFAULT_LINKER:STRING=lld
  -DCLANG_DEFAULT_UNWINDLIB=libunwind

  -DLIBUNWIND_USE_COMPILER_RT:BOOL=ON
  -DLIBUNWIND_ENABLE_SHARED:BOOL=ON
  
  -DLLVM_USE_STATIC_ZSTD:BOOL=ON

  -DCMAKE_INSTALL_PREFIX:PATH="${INSTALL_PATH}"
  -DCLANG_CONFIG_FILE_SYSTEM_DIR:PATH="${INSTALL_PATH}/etc"

  -DLLVM_INSTALL_BINUTILS_SYMLINKS:BOOL=ON
  -DLLVM_INSTALL_CCTOOLS_SYMLINKS:BOOL=ON

  -DCLANG_INCLUDE_TESTS:BOOL=OFF
  -DLLVM_INCLUDE_TESTS:BOOL=OFF
  -DLLVM_ENABLE_TERMINFO:BOOL=ON

  -DLLVM_BUILD_TOOLS:BOOL=ON

  -DHAVE_CXX_ATOMICS64_WITHOUT_LIB:BOOL=ON
  -DHAVE_CXX_ATOMICS_WITHOUT_LIB:BOOL=ON

  -DLLVM_PARALLEL_COMPILE_JOBS:STRING=17
  -DLLVM_PARALLEL_LINK_JOBS:STRING=2

  -DLLVM_ENABLE_LLD:BOOL=ON

  -DCMAKE_OSX_DEPLOYMENT_TARGET:STRING="${MACOS_VERSION}"

  -DCOMPILER_RT_BUILD_BUILTINS:BOOL=ON
  -DCOMPILER_RT_ENABLE_IOS:BOOL=OFF
  -DCOMPILER_RT_ENABLE_WATCHOS:BOOL=OFF
  -DCOMPILER_RT_ENABLE_TVOS:BOOL=OFF
  -DCOMPILER_RT_ENABLE_MACCATALYST:BOOL=OFF

  -DCOMPILER_RT_BUILD_LIBFUZZER:BOOL=ON
  -DCOMPILER_RT_BUILD_MEMPROF:BOOL=ON
  -DCOMPILER_RT_BUILD_PROFILE:BOOL=ON
  -DCOMPILER_RT_BUILD_SANITIZERS:BOOL=ON
  -DCOMPILER_RT_BUILD_XRAY:BOOL=ON

  -DLIBCXX_CXX_ABI:STRING=libcxxabi
  -DLIBCXX_USE_COMPILER_RT:BOOL=ON
  -DLIBCXX_HAS_GCC_S_LIB:BOOL=OFF
  -DLIBCXXABI_USE_LLVM_UNWINDER:BOOL=ON
  -DLIBCXXABI_USE_COMPILER_RT:BOOL=ON
  -DLIBUNWIND_USE_COMPILER_RT:BOOL=ON
  -DLLVM_ENABLE_LIBCXX:BOOL=ON
  -DLIBCXXABI_USE_COMPILER_RT:BOOL=ON
  -DLIBCXX_ENABLE_ABI_LINKER_SCRIPT:BOOL=ON

  -DLLVM_ENABLE_RTTI:BOOL=ON
  -DLLVM_ENABLE_FFI:BOOL=ON
  -DLLVM_ENABLE_EH:BOOL=ON
)

echo cmake "${cmake_args[@]}" -S llvm -G Ninja -B "${BUILD_DIR}" && ninja -C "${BUILD_DIR}" && ninja -C "${BUILD_DIR}" install
cmake "${cmake_args[@]}" -S llvm -G Ninja -B "${BUILD_DIR}" && ninja -C "${BUILD_DIR}" && ninja -C "${BUILD_DIR}" install

mkdir -p ${INSTALL_PATH}/etc

if [ ! -f${INSTALL_PATH}/lib/clang/${LLVM_VERSION_MAJOR}/lib/darwin ]; then
  ln -fs ${INSTALL_PATH}/lib/darwin ${INSTALL_PATH}/lib/clang/${LLVM_VERSION_MAJOR}/lib/darwin
fi

cat >${INSTALL_PATH}/etc/${LLVM_CLANG_C_CONFIG_FILE_NAME} <<EOF
-fuse-ld=lld -Wl,-rpath,${INSTALL_PATH}/lib -Wl,-rpath,${INSTALL_PATH}/lib/darwin
EOF

cat >${INSTALL_PATH}/etc/${LLVM_CLANG_CPP_CONFIG_FILE_NAME} <<EOF
-fuse-ld=lld -Wl,-rpath,${INSTALL_PATH}/lib -Wl,-rpath,${INSTALL_PATH}/lib/darwin -lc++abi
EOF

custom_dsymutil="${INSTALL_PATH}/bin/dsymutil_no_warnings"
cat >${custom_dsymutil} <<EOF
#!/bin/sh
${INSTALL_PATH}/bin/dsymutil \$@ 2>/dev/null
EOF
chmod a+x ${custom_dsymutil}

codesign -s lldb_codesign --entitlements lldb/tools/debugserver/resources/debugserver-macosx-entitlements.plist -f ${INSTALL_PATH}/bin/debugserver

I suspect you'll get around a lot of your difficulties by setting

-DCMAKE_MACOSX_RPATH=ON
-DCMAKE_INSTALL_RPATH='@loader_path/../lib'

Will try it. I have the hard-coded RPATHs in there already. Maybe -DCMAKE_MACOSX_RPATH=ON will help though. I forget why I turned that off. Possibly due to libcxx weirdness.

It all works now with llvm 19 on x86_64 macOS. auto-signing the lldb debug server as well. Has worked since late llvm 18.