class Rake::ExtensionTask

def find_make
  candidates = ["gmake", "make"]
  paths = (ENV["PATH"] || "").split(File::PATH_SEPARATOR)
  paths = paths.collect do |path|
    Pathname(path).cleanpath
  end
  exeext = RbConfig::CONFIG["EXEEXT"]
  candidates.each do |candidate|
    paths.each do |path|
      make = path + "#{candidate}#{exeext}"
      return make.to_s if make.executable?
    end
  end
  nil
end