gistfile1.rb

  def compile_object(path, output)
    base = File.basename(path, '.rb') 
    output ||= File.join(File.dirname(path), base + '.o')

    # Generate init function (must be unique).
    uuid = `uuidgen`.strip.gsub('-', '')
    init_func = "MREP_#{uuid}"

    tmp_objs = []
    @archs.each do |arch|
      # Compile the file into LLVM bitcode.
      bc = gen_tmpfile(base + arch, 'bc')
      execute("arch -#{arch} #{@macruby} --emit-llvm \"#{bc}\" #{init_func} \"#{path}\"")

      # Compile the bitcode as assembly.
      asm = gen_tmpfile(base + arch, 's')
      execute("#{@llc} -f \"#{bc}\" -o=\"#{asm}\" -march=#{llc_arch(arch)} -relocation-model=pic -enable-eh")

      # Compile the assembly.
      tmp_obj = gen_tmpfile(base + arch, 'o')
      execute("#{@gcc} -c -arch #{arch} \"#{asm}\" -o \"#{tmp_obj}\"")
      tmp_objs << tmp_obj
    end

    # Link the architecture objects.
    cli_tmp_objs = tmp_objs.map do |obj|
      '"' + obj + '"'
    end
    execute("#{@lipo} -create #{cli_tmp_objs.join(' ')} -output \"#{output}\"")

    [output, init_func]
  end

gistfile2.rb

  def compile_executable(objs_data, output)
    output ||= 'a.out'
    raise if objs_data.empty?
    die "first object file must be a Ruby source file or object" if objs_data[0][1] == nil

    # Generate main file.
    main_txt = <<EOS
extern "C" {
    void ruby_sysinit(int *, char ***);
    void ruby_init(void);
    void ruby_init_loadpath(void);
    void ruby_script(const char *);
    void ruby_set_argv(int, char **);
    void rb_vm_init_compiler(void);
    void rb_vm_aot_feature_provide(const char *, void *);
    void *rb_vm_top_self(void);
    void rb_vm_print_current_exception(void);
    void rb_exit(int);
EOS
    objs_data.each do |obj, init_func|
      next if init_func == nil
      main_txt << "void *#{init_func}(void *, void *);\n"
    end
    main_txt << <<EOS
}

int main(int argc, char **argv)
{
    const char *progname = argv[0];
    ruby_sysinit(&argc, &argv);
    if (argc > 0) {
	argc--;
        argv++;
    }
    ruby_init();
    ruby_init_loadpath();
    ruby_set_argv(argc, argv);
    rb_vm_init_compiler();
    ruby_script(progname);
    try {
EOS
    objs_data[1..-1].each do |obj, init_func|
      next if init_func == nil
      main_txt << "rb_vm_aot_feature_provide(\"#{feature_name(obj)}\", (void *)#{init_func});\n"
    end
    main_txt << <<EOS
        void *self = rb_vm_top_self();
        #{objs_data[0][1]}(self, 0);
    }
    catch (...) {
	rb_vm_print_current_exception();
	rb_exit(1);
    }
    rb_exit(0);
}
EOS

    # Prepare objects.
    objs = []
    objs_data.each { |o, _| objs << o }

    # Compile main file.
    main = gen_tmpfile('main', 'mm')
    File.open(main, 'w') { |io| io.write(main_txt) }
    main_o = gen_tmpfile('main', 'o')
    execute("#{@gcxx} \"#{main}\" -c #{arch_flags} -o \"#{main_o}\" -fobjc-gc")
    objs.unshift(main_o)

    # Link all objects into executable.
    linkf = @static ? 
      "-L#{RbConfig::CONFIG['libdir']} #{RbConfig::CONFIG['LIBRUBYARG_STATIC_REALLY']}" :
      "-framework MacRuby -lobjc"
    line = "#{@gcxx} -o \"#{output}\" #{arch_flags} #{linkf} "
    objs.each { |o| line << " \"#{o}\"" }
    execute(line)
  end