add llvm-12

Formula/llvm-12.rb

@@ -0,0 +1,158 @@
+class Llvm12 < Formula
+  desc "Next-gen compiler infrastructure"
+  homepage "http://llvm.org/"
+  # The LLVM Project is under the Apache License v2.0 with LLVM Exceptions
+  license "Apache-2.0" => { with: "LLVM-exception" }
+  revision 1
+
+  stable do
+    url "https://github.com/llvm/llvm-project/releases/download/llvmorg-12.0.0/llvm-project-12.0.0.src.tar.xz"
+    sha256 "9ed1688943a4402d7c904cc4515798cdb20080066efa010fe7e1f2551b423628"
+  end
+
+  # bottle do
+  #   root_url "https://github.com/llvm-hs/homebrew-llvm/releases/download/v12.0.0"
+  #   sha256 cellar: :any, big_sur: ""
+  # end
+
+  # Clang cannot find system headers if Xcode CLT is not installed
+  pour_bottle? do
+    on_macos do
+      reason "The bottle needs the Xcode CLT to be installed."
+      satisfy { MacOS::CLT.installed? }
+    end
+  end
+
+  # http://releases.llvm.org/12.0.0/docs/GettingStarted.html#requirements
+  depends_on "cmake" => :build
+
+  uses_from_macos "libedit"
+  uses_from_macos "libffi", since: :catalina
+  uses_from_macos "libxml2"
+  uses_from_macos "ncurses"
+  uses_from_macos "zlib"
+
+  # version suffix
+  def version
+    "12"
+  end
+
+  # http://releases.llvm.org/12.0.0/docs/CMake.html
+  def install
+    projects = %w[
+      clang
+      clang-tools-extra
+      compiler-rt
+      libcxx
+      libcxxabi
+      libunwind
+      lld
+      lldb
+      mlir
+      openmp
+      polly
+    ]
+    runtimes = %w[
+    ]
+
+    # Apple's libstdc++ is too old to build LLVM
+    ENV.libcxx if ENV.compiler == :clang
+
+    # compiler-rt has some iOS simulator features that require i386 symbols. I'm
+    # assuming the rest of clang also needs support for 32-bit compilation to
+    # work correctly, but if not, perhaps universal binaries could be limited to
+    # compiler-rt. LLVM makes this somewhat easier because compiler-rt can
+    # almost be treated as an entirely different build from LLVM.
+    ENV.permit_arch_flags
+
+    install_prefix = lib/"llvm-#{version}"
+
+    args = %W[
+      -DCMAKE_BUILD_TYPE=Release
+      -DCMAKE_INSTALL_PREFIX=#{install_prefix}
+      -DLLVM_ENABLE_PROJECTS=#{projects.join(";")}
+      -DLLVM_ENABLE_RUNTIMES=#{runtimes.join(";")}
+      -DLLVM_TARGETS_TO_BUILD=all
+      -DLLVM_ENABLE_ASSERTIONS=ON
+      -DLLVM_OPTIMIZED_TABLEGEN=ON
+      -DLLVM_INCLUDE_DOCS=OFF
+      -DLLVM_INCLUDE_TESTS=OFF
+      -DLLVM_ENABLE_RTTI=ON
+      -DLLVM_ENABLE_EH=ON
+      -DLLVM_INSTALL_UTILS=ON
+      -DLLVM_ENABLE_Z3_SOLVER=OFF
+      -DLLVM_BUILD_EXTERNAL_COMPILER_RT=ON
+      -DLLVM_BUILD_LLVM_C_DYLIB=ON
+      -DLLVM_LINK_LLVM_DYLIB=ON
+      -DLLVM_ENABLE_LIBCXX=ON
+      -DLLVM_ENABLE_FFI=ON
+      -DLLVM_CREATE_XCODE_TOOLCHAIN=ON
+      -DLLVM_CREATE_XCODE_TOOLCHAIN=#{MacOS::Xcode.installed? ? "ON" : "OFF"}
+      -DLLDB_USE_SYSTEM_DEBUGSERVER=ON
+    ]
+
+    if MacOS.version >= :catalina
+      args << "-DFFI_INCLUDE_DIR=#{MacOS.sdk_path}/usr/include/ffi"
+      args << "-DFFI_LIBRARY_DIR=#{MacOS.sdk_path}/usr/lib"
+    else
+      args << "-DFFI_INCLUDE_DIR=#{Formula["libffi"].opt_include}"
+      args << "-DFFI_LIBRARY_DIR=#{Formula["libffi"].opt_lib}"
+    end
+
+    sdk = MacOS.sdk_path_if_needed
+    args << "-DDEFAULT_SYSROOT=#{sdk}" if sdk
+
+    if MacOS.version == :mojave && MacOS::CLT.installed?
+      # Mojave CLT linker via software update is older than Xcode.
+      # Use it to retain compatibility.
+      args << "-DCMAKE_LINKER=/Library/Developer/CommandLineTools/usr/bin/ld"
+    end
+
+    llvmpath = buildpath/"llvm"
+    mkdir llvmpath/"build" do
+      system "cmake", "-G", "Unix Makefiles", "..", *(std_cmake_args + args)
+      system "cmake", "--build", "."
+      system "cmake", "--build", ".", "--target", "install"
+      system "cmake", "--build", ".", "--target", "install-xcode-toolchain" if MacOS::Xcode.installed?
+    end
+
+    # replace the existing "clang -> clang-12" symlink
+    rm install_prefix/"bin/clang"
+    mv install_prefix/"bin/clang-#{version}", install_prefix/"bin/clang"
+
+    # These versioned .dylib symlinks are missing for some reason
+    # Note that we use relative symlinks
+    ln_s "libLLVM.dylib", install_prefix/"lib/libLLVM-#{version}.dylib"
+
+    Dir.glob(install_prefix/"bin/*") do |exec_path|
+      basename = File.basename(exec_path)
+      bin.install_symlink exec_path => "#{basename}-#{version}"
+    end
+
+    Dir.glob(install_prefix/"share/man/man1/*") do |manpage|
+      basename = File.basename(manpage, ".1")
+      man1.install_symlink manpage => "#{basename}-#{version}.1"
+    end
+  end
+
+  def caveats
+    <<~EOS
+      Extra tools are installed in #{opt_share}/clang-#{version}
+
+      To link to libc++, something like the following is required:
+        CXX="clang++-#{version} -stdlib=libc++"
+        CXXFLAGS="$CXXFLAGS -nostdinc++ -I#{opt_lib}/llvm-#{version}/include/c++/v1"
+        LDFLAGS="$LDFLAGS -L#{opt_lib}/llvm-#{version}/lib"
+    EOS
+  end
+
+  test do
+    assert_equal prefix.to_s, shell_output("#{bin}/llvm-config-#{version} --prefix").chomp
+
+    # 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-#{version}/share/llvm/cmake/LLVMConfig.cmake").read)
+    system "#{bin}/llvm-config-#{version}", "--version"
+  end
+end
+