build-clang.py ============== A script to build clang from source. ``` usage: build-clang.py [-h] -c CONFIG [--clean] optional arguments: -h, --help show this help message and exit -c CONFIG, --config CONFIG Clang configuration file --clean Clean the build directory ``` Pre-requisites -------------- * Working build toolchain. * git * CMake * Ninja * Python 2.7 and 3 Please use the latest available CMake for your platform to avoid surprises. Config file format ------------------ build-clang.py accepts a JSON config format with the following fields: * stages: Use 1, 2, 3 or 4 to select different compiler stages. The default is 2. * cc: Path to the bootsraping C Compiler. * cxx: Path to the bootsraping C++ Compiler. * as: Path to the assembler tool. * ar: Path to the library archiver tool. * ranlib: Path to the ranlib tool (optional). * ld: Path to the linker. * patches: Optional list of patches to apply. * build_type: The type of build to make. Supported types: Release, Debug, RelWithDebInfo or MinSizeRel. * targets: The targets supported by the final stage LLVM/clang. * build_clang_tidy: Whether to build clang-tidy with the Mozilla checks imported. The default is false. * osx_cross_compile: Whether to invoke CMake for OS X cross compile builds. * assertions: Whether to enable LLVM assertions. The default is false. * pgo: Whether to build with PGO (requires stages == 4). The default is false. The revisions are defined in taskcluster/kinds/fetch/toolchains.yml. They are usually commit sha1s corresponding to upstream tags. Environment Variables --------------------- The following environment variables are used for cross-compile builds targeting OS X on Linux. * CROSS_SYSROOT: Path to the OS X SDK directory for cross compile builds.