LLVM 3.8 with clang, libc++, and libc++abi + CMake toolchain file for Linuxbrew

llvm38.rb

class CodesignRequirement < Requirement
  include FileUtils
  fatal true

  satisfy(:build_env => false) do
    mktemp do
      touch "llvm_check.txt"
      quiet_system "/usr/bin/codesign", "-s", "lldb_codesign", "--dryrun", "llvm_check.txt"
    end
  end

  def message
    <<-EOS.undent
      lldb_codesign identity must be available to build with LLDB.
      See: https://llvm.org/svn/llvm-project/lldb/trunk/docs/code-signing.txt
    EOS
  end
end

class Llvm38 < Formula
  desc "The LLVM Compiler Infrastructure"
  homepage "http://llvm.org/"

  stable do
    url "http://llvm.org/releases/3.8.0/llvm-3.8.0.src.tar.xz"
    sha256 "555b028e9ee0f6445ff8f949ea10e9cd8be0d084840e21fbbe1d31d51fc06e46"

    resource "clang" do
      url "http://llvm.org/releases/3.8.0/cfe-3.8.0.src.tar.xz"
      sha256 "04149236de03cf05232d68eb7cb9c50f03062e339b68f4f8a03b650a11536cf9"
    end

    resource "clang-tools-extra" do
      url "http://llvm.org/releases/3.8.0/clang-tools-extra-3.8.0.src.tar.xz"
      sha256 "afbda810106a6e64444bc164b921be928af46829117c95b996f2678ce4cb1ec4"
    end

    resource "compiler-rt" do
      url "http://llvm.org/releases/3.8.0/compiler-rt-3.8.0.src.tar.xz"
      sha256 "c8d3387e55f229543dac1941769120f24dc50183150bf19d1b070d53d29d56b0"
    end

    resource "polly" do
      url "http://llvm.org/releases/3.8.0/polly-3.8.0.src.tar.xz"
      sha256 "84cbabc0b6a10a664797907d291b6955d5ea61aef04e3f3bb464e42374d1d1f2"
    end

    resource "lld" do
      url "http://llvm.org/releases/3.8.0/lld-3.8.0.src.tar.xz"
      sha256 "94704dda228c9f75f4403051085001440b458501ec97192eee06e8e67f7f9f0c"
    end

    resource "lldb" do
      url "http://llvm.org/releases/3.8.0/lldb-3.8.0.src.tar.xz"
      sha256 "e3f68f44147df0433e7989bf6ed1c58ff28d7c68b9c47553cb9915f744785a35"
    end

    resource "libcxx" do
      url "http://llvm.org/releases/3.8.0/libcxx-3.8.0.src.tar.xz"
      sha256 "36804511b940bc8a7cefc7cb391a6b28f5e3f53f6372965642020db91174237b"
    end

    if OS.linux? or MacOS.version <= :snow_leopard
      resource "libcxxabi" do
        url "http://llvm.org/releases/3.8.0/libcxxabi-3.8.0.src.tar.xz"
        sha256 "c5ee0871aff6ec741380c4899007a7d97f0b791c81df69d25b744eebc5cee504"
      end
    end
  end
  bottle do
    sha256 "d11c8af13e3560b99da7444ea4b98766aca1c2cde2c4d7d9d70450769f80106d" => :el_capitan
    sha256 "992e53288649668ce8125a0fda5b4e96c0e33871b377087c582f55a055f8bc1c" => :yosemite
    sha256 "aaca71557a11144d9fb8276f791282c910f7172dbbe7a6f63a146d718d058b16" => :mavericks
  end


  head do
    url "http://llvm.org/git/llvm.git", :branch => "release_38"

    resource "clang" do
      url "http://llvm.org/git/clang.git", :branch => "release_38"
    end

    resource "clang-tools-extra" do
      url "http://llvm.org/git/clang-tools-extra.git", :branch => "release_38"
    end

    resource "compiler-rt" do
      url "http://llvm.org/git/compiler-rt.git", :branch => "release_38"
    end

    resource "polly" do
      url "http://llvm.org/git/polly.git", :branch => "release_38"
    end

    resource "lld" do
      url "http://llvm.org/git/lld.git"
    end

    resource "lldb" do
      url "http://llvm.org/git/lldb.git", :branch => "release_38"
    end

    resource "libcxx" do
      url "http://llvm.org/git/libcxx.git", :branch => "release_38"
    end

    if OS.linux? or MacOS.version <= :snow_leopard
      resource "libcxxabi" do
        url "http://llvm.org/git/libcxxabi.git", :branch => "release_38"
      end
    end
  end

  option :universal
  option "with-lld", "Build LLD linker"
  option "with-lldb", "Build LLDB debugger"
  option "with-asan", "Include support for -faddress-sanitizer (from compiler-rt)"
  option "with-python", "Build lldb bindings against the python in PATH instead of system Python"
  option "without-shared", "Don't build LLVM as a shared library"
  option "without-assertions", "Speeds up LLVM, but provides less debug information"

  depends_on "gnu-sed" => :build
  depends_on "gmp"
  depends_on "libffi"
  depends_on :python => :optional
  depends_on "cmake" => :build

  if build.with? "lldb"
    depends_on "swig"
    depends_on CodesignRequirement
  end

  # version suffix
  def ver
    "3.8"
  end

  # LLVM installs its own standard library which confuses stdlib checking.
  cxxstdlib_check :skip

  # Apple's libstdc++ is too old to build LLVM
  fails_with :gcc
  fails_with :llvm

  def install
    # One of llvm makefiles relies on gnu sed behavior to generate CMake modules correctly
    ENV.prepend_path "PATH", "#{Formula["gnu-sed"].opt_libexec}/gnubin"
    # Apple's libstdc++ is too old to build LLVM
    ENV.libcxx if ENV.compiler == :clang

    clang_buildpath = buildpath/"tools/clang"
    libcxx_buildpath = buildpath/"projects/libcxx"
    libcxxabi_buildpath = buildpath/"projects/libcxxabi"

    clang_buildpath.install resource("clang")
    libcxx_buildpath.install resource("libcxx")
    (buildpath/"tools/polly").install resource("polly")
    (buildpath/"tools/clang/tools/extra").install resource("clang-tools-extra")
    (buildpath/"tools/lld").install resource("lld") if build.with? "lld"
    (buildpath/"tools/lldb").install resource("lldb") if build.with? "lldb"
    (buildpath/"projects/compiler-rt").install resource("compiler-rt") if build.with? "asan"

    libcxxabi_buildpath.install resource("libcxxabi") if OS.linux? or MacOS.version <= :snow_leopard

    if build.universal?
      ENV.permit_arch_flags
      ENV["UNIVERSAL"] = "1"
      ENV["UNIVERSAL_ARCH"] = Hardware::CPU.universal_archs.join(" ")
    end

    ENV["REQUIRES_RTTI"] = "1"

    install_prefix = lib/"llvm-#{ver}"

    args = %W[
      -DCMAKE_C_FLAGS_RELEASE=-DNDEBUG
      -DCMAKE_CXX_FLAGS_RELEASE=-DNDEBUG
      -DCMAKE_INSTALL_PREFIX=#{install_prefix}
      -DCMAKE_BUILD_TYPE=Release
      -DCMAKE_FIND_FRAMEWORK=LAST
      -DCMAKE_VERBOSE_MAKEFILE=On
      -Wno-dev
      -DLLVM_OPTIMIZED_TABLEGEN=On
      -DLLVM_ENABLE_RTTI=On
    ]

    # clang needs to know the correct search path
    args << "-DGCC_INSTALL_PREFIX=#{Formula["gcc"].opt_prefix}" unless OS.mac?
    args << "-DBUILD_SHARED_LIBS=Off" if build.without? "shared"
    args << "-DLLVM_ENABLE_ASSERTIONS=On" if build.with? "assertions"
    args << "-DLLVM_ENABLE_FFI=On" if build.with? "libffi"
    # Fix for LineEditor.cpp:17:22: fatal error: histedit.h: No such file or directory
    #args << "-DCMAKE_CXX_FLAGS=#{ENV["CPPFLAGS"]} #{ENV["CXXFLAGS"]}" unless OS.mac?

    mktemp do
      system "cmake", "-G", "Unix Makefiles", buildpath, *args
      system "make"
      system "make", "install"
    end

    (share/"clang/tools").install Dir["tools/clang/tools/scan-{build,view}"]
    inreplace share/"clang/tools/scan-build/bin/scan-build", "$RealBin/bin/clang", bin/"clang-#{ver}"
    bin.install_symlink share/"clang/tools/scan-build/bin/scan-build", share/"clang/tools/scan-view/bin/scan-view"
    man1.install_symlink share/"clang/tools/scan-build/man/scan-build.1"

    (lib/"python2.7/site-packages").install "bindings/python/llvm" => "llvm-#{ver}",
                                            clang_buildpath/"bindings/python/clang" => "clang-#{ver}"
    (lib/"python2.7/site-packages").install_symlink install_prefix/"lib/python2.7/site-packages/lldb" => "lldb-#{ver}" if build.with? "lldb"

    Dir.glob(install_prefix/"bin/*") do |exec_path|
      basename = File.basename(exec_path)
      bin.install_symlink exec_path => "#{basename}-#{ver}"
    end

    Dir.glob(install_prefix/"share/man/man1/*") do |manpage|
      basename = File.basename(manpage, ".1")
      man1.install_symlink manpage => "#{basename}-#{ver}.1"
    end
  end

  def post_install
    if OS.linux?
      # Create a CMake toolchain file
      # See https://cmake.org/cmake/help/v3.0/manual/cmake-toolchains.7.html

      install_prefix = lib/"llvm-#{ver}"
      toolchain = install_prefix/"share/clang/cmake/ClangToolchain.cmake"
      toolchain_str = <<-EOS.undent
        set(CMAKE_SYSTEM_NAME Linux)

        set(CMAKE_C_COMPILER clang-#{ver})
        set(CMAKE_CXX_COMPILER clang++-#{ver})

        set(LLVM_#{ver}_LINKER_FLAGS "${LLVM_#{ver}_LINKER_FLAGS} -Wl,-rpath,#{HOMEBREW_PREFIX}/lib")
        set(LLVM_#{ver}_LINKER_FLAGS "${LLVM_#{ver}_LINKER_FLAGS} -Wl,-rpath,#{opt_lib}/llvm-#{ver}/lib")
        set(LLVM_#{ver}_LINKER_FLAGS "${LLVM_#{ver}_LINKER_FLAGS} -L#{HOMEBREW_PREFIX}/lib")
        set(LLVM_#{ver}_LINKER_FLAGS "${LLVM_#{ver}_LINKER_FLAGS} -L#{opt_lib}/llvm-#{ver}/lib")
      EOS
      
      if Formula["glibc"].installed?
        toolchain_str += <<-EOS.undent
          set(LLVM_#{ver}_LINKER_FLAGS "${LLVM_#{ver}_LINKER_FLAGS} -Wl,-dynamic-linker,#{HOMEBREW_PREFIX}/lib/ld.so")
        EOS
      end
        
      toolchain_str += <<-EOS.undent
        set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} ${LLVM_#{ver}_LINKER_FLAGS}" CACHE STRING "Linker flags to be used to create executables.")
        set(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} ${LLVM_#{ver}_LINKER_FLAGS}" CACHE STRING "Linker flags to be used to create shared libraries.")
      EOS

      toolchain.write toolchain_str
    end
  end

  def caveats; <<-EOS.undent
    Extra tools are installed in #{opt_share}/clang-#{ver}

    To link to libc++, something like the following is required:
      CXX="clang++-#{ver} -stdlib=libc++"
      CXXFLAGS="$CXXFLAGS -nostdinc++ -I#{opt_lib}/llvm-#{ver}/include/c++/v1"
      LDFLAGS="$LDFLAGS -L#{opt_lib}/llvm-#{ver}/lib"
    EOS
  end

  test do
    # test for sed errors since some llvm makefiles assume that sed
    # understands '\n' which is true for gnu sed and not for bsd sed.
    assert_no_match /PATH\)n/, (lib/"llvm-3.8/share/llvm/cmake/LLVMConfig.cmake").read
    system "#{bin}/llvm-config-#{ver}", "--version"
  end
end