def activate_dependencies
    self.runtime_dependencies.each do |spec_dep|
      if loaded = Gem.loaded_specs[spec_dep.name]
        next if spec_dep.matches_spec? loaded

        msg = "can't satisfy '#{spec_dep}', already activated '#{loaded.full_name}'"
        e = Gem::LoadError.new msg
        e.name = spec_dep.name

        raise e
      end

      specs = spec_dep.to_specs

      if specs.size == 1 then
        specs.first.activate
      else
        name = spec_dep.name
        Gem.unresolved_deps[name] = Gem.unresolved_deps[name].merge spec_dep
      end
    end

    Gem.unresolved_deps.delete self.name
  end
#
Activate all unambiguously resolved runtime dependencies of this
spec. Add any ambigous dependencies to the unresolved list to be
resolved later, as needed.