class GccAT6 < Formula
  def arch
    if Hardware::CPU.type == :intel
      if MacOS.prefer_64_bit?
        "x86_64"
      else
        "i686"
      end
    elsif Hardware::CPU.type == :ppc
      if MacOS.prefer_64_bit?
        "powerpc64"
      else
        "powerpc"
      end
    end
  end

  def osmajor
    `uname -r`.chomp
  end

  desc "The GNU Compiler Collection"
  homepage "https://gcc.gnu.org"
  url "https://ftpmirror.gnu.org/gcc/gcc-6.2.0/gcc-6.2.0.tar.bz2"
  mirror "https://ftp.gnu.org/gnu/gcc/gcc-6.2.0/gcc-6.2.0.tar.bz2"
  sha256 "9944589fc722d3e66308c0ce5257788ebd7872982a718aa2516123940671b7c5"
  revision 1

  bottle do
    sha256 "bfb52caec32dc9af53ff77582e20916ff136b74868f1e30296f3c43d69894630" => :sierra
    sha256 "190c127c503e9aaa845b24d8effdbdc2a0d180ee6cd7baf7e34b63f9766acb72" => :el_capitan
    sha256 "c5b1163b6e5cb09d18fb20c4d0cd025142011d115ed60c1267ba40ff5bc0cdd5" => :yosemite
  end

  # GCC's Go compiler is not currently supported on Mac OS X.
  # See: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=46986
  option "with-java", "Build the gcj compiler"
  option "with-all-languages", "Enable all compilers and languages, except Ada"
  option "with-nls", "Build with native language support (localization)"
  option "with-profiled-build", "Make use of profile guided optimization when bootstrapping GCC"
  option "with-jit", "Build the jit compiler"
  option "without-fortran", "Build without the gfortran compiler"
  # enabling multilib on a host that can"t run 64-bit results in build failures
  option "without-multilib", "Build without multilib support" if MacOS.prefer_64_bit?

  depends_on "gmp"
  depends_on "libmpc"
  depends_on "mpfr"
  depends_on "isl@0.14"
  depends_on "ecj" if build.with?("java") || build.with?("all-languages")

  if MacOS.version < :leopard
    # The as that comes with Tiger isn't capable of dealing with the
    # PPC asm that comes in libitm
    depends_on "cctools" => :build
  end

  # The bottles are built on systems with the CLT installed, and do not work
  # out of the box on Xcode-only systems due to an incorrect sysroot.
  def pour_bottle?
    MacOS::CLT.installed?
  end

  # GCC bootstraps itself, so it is OK to have an incompatible C++ stdlib
  cxxstdlib_check :skip

  # Fix for libgccjit.so linkage on Darwin
  # https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64089
  patch :DATA

  def install
    # GCC will suffer build errors if forced to use a particular linker.
    ENV.delete "LD"

    if MacOS.version < :leopard
      ENV["AS"] = ENV["AS_FOR_TARGET"] = "#{Formula["cctools"].bin}/as"
    end

    if build.with? "all-languages"
      # Everything but Ada, which requires a pre-existing GCC Ada compiler
      # (gnat) to bootstrap. GCC 4.6.0 add go as a language option, but it is
      # currently only compilable on Linux.
      languages = %w[c c++ fortran java objc obj-c++ jit]
    else
      # C, C++, ObjC compilers are always built
      languages = %w[c c++ objc obj-c++]

      languages << "fortran" if build.with? "fortran"
      languages << "java" if build.with? "java"
      languages << "jit" if build.with? "jit"
    end

    version_suffix = version.to_s.slice(/\d/)

    # Even when suffixes are appended, the info pages conflict when
    # install-info is run so pretend we have an outdated makeinfo
    # to prevent their build.
    ENV["gcc_cv_prog_makeinfo_modern"] = "no"

    args = [
      "--build=#{arch}-apple-darwin#{osmajor}",
      "--prefix=#{prefix}",
      "--libdir=#{lib}/gcc/#{version_suffix}",
      "--enable-languages=#{languages.join(",")}",
      # Make most executables versioned to avoid conflicts.
      "--program-suffix=-#{version_suffix}",
      "--with-gmp=#{Formula["gmp"].opt_prefix}",
      "--with-mpfr=#{Formula["mpfr"].opt_prefix}",
      "--with-mpc=#{Formula["libmpc"].opt_prefix}",
      "--with-isl=#{Formula["isl@0.14"].opt_prefix}",
      "--with-system-zlib",
      "--enable-libstdcxx-time=yes",
      "--enable-stage1-checking",
      "--enable-checking=release",
      "--enable-lto",
      # Use 'bootstrap-debug' build configuration to force stripping of object
      # files prior to comparison during bootstrap (broken by Xcode 6.3).
      "--with-build-config=bootstrap-debug",
      # A no-op unless --HEAD is built because in head warnings will
      # raise errors. But still a good idea to include.
      "--disable-werror",
      "--with-pkgversion=Homebrew GCC #{pkg_version} #{build.used_options*" "}".strip,
      "--with-bugurl=https://github.com/Homebrew/homebrew-core/issues",
    ]

    # "Building GCC with plugin support requires a host that supports
    # -fPIC, -shared, -ldl and -rdynamic."
    args << "--enable-plugin" if MacOS.version > :tiger

    # The pre-Mavericks toolchain requires the older DWARF-2 debugging data
    # format to avoid failure during the stage 3 comparison of object files.
    # See: http://gcc.gnu.org/bugzilla/show_bug.cgi?id=45248
    args << "--with-dwarf2" if MacOS.version <= :mountain_lion

    args << "--disable-nls" if build.without? "nls"

    if build.with?("java") || build.with?("all-languages")
      args << "--with-ecj-jar=#{Formula["ecj"].opt_share}/java/ecj.jar"
    end

    if !MacOS.prefer_64_bit? || build.without?("multilib")
      args << "--disable-multilib"
    else
      args << "--enable-multilib"
    end

    args << "--enable-host-shared" if build.with?("jit") || build.with?("all-languages")

    # Ensure correct install names when linking against libgcc_s;
    # see discussion in https://github.com/Homebrew/homebrew/pull/34303
    inreplace "libgcc/config/t-slibgcc-darwin", "@shlib_slibdir@", "#{HOMEBREW_PREFIX}/lib/gcc/#{version_suffix}"

    mkdir "build" do
      unless MacOS::CLT.installed?
        # For Xcode-only systems, we need to tell the sysroot path.
        # "native-system-headers" will be appended
        args << "--with-native-system-header-dir=/usr/include"
        args << "--with-sysroot=#{MacOS.sdk_path}"
      end

      system "../configure", *args

      if build.with? "profiled-build"
        # Takes longer to build, may bug out. Provided for those who want to
        # optimise all the way to 11.
        system "make", "profiledbootstrap"
      else
        system "make", "bootstrap"
      end

      # At this point `make check` could be invoked to run the testsuite. The
      # deja-gnu and autogen formulae must be installed in order to do this.
      system "make", "install"
    end

    # Handle conflicts between GCC formulae.
    # Rename man7.
    Dir.glob(man7/"*.7") { |file| add_suffix file, version_suffix }
    # Even when we disable building info pages some are still installed.
    info.rmtree
  end

  def add_suffix(file, suffix)
    dir = File.dirname(file)
    ext = File.extname(file)
    base = File.basename(file, ext)
    File.rename file, "#{dir}/#{base}-#{suffix}#{ext}"
  end

  test do
    (testpath/"hello-c.c").write <<-EOS.undent
      #include <stdio.h>
      int main()
      {
        puts("Hello, world!");
        return 0;
      }
    EOS
    system bin/"gcc-6", "-o", "hello-c", "hello-c.c"
    assert_equal "Hello, world!\n", `./hello-c`
  end
end

__END__
--- a/gcc/jit/Make-lang.in	2015-02-03 17:19:58.000000000 +0000
+++ b/gcc/jit/Make-lang.in	2015-04-08 22:08:24.000000000 +0100
@@ -85,8 +85,7 @@
	     $(jit_OBJS) libbackend.a libcommon-target.a libcommon.a \
	     $(CPPLIB) $(LIBDECNUMBER) $(LIBS) $(BACKENDLIBS) \
	     $(EXTRA_GCC_OBJS) \
-	     -Wl,--version-script=$(srcdir)/jit/libgccjit.map \
-	     -Wl,-soname,$(LIBGCCJIT_SONAME)
+	     -Wl,-install_name,$(LIBGCCJIT_SONAME)

 $(LIBGCCJIT_SONAME_SYMLINK): $(LIBGCCJIT_FILENAME)
	ln -sf $(LIBGCCJIT_FILENAME) $(LIBGCCJIT_SONAME_SYMLINK)