gcc 4.8.4错误：参数包未使用'...'扩展

Question

我在code的以下位置收到错误：

template <typename Container, typename... Ts>
Gen<Container> container(Gen<Ts>... gens) {
  using Strategy = detail::GenericContainerStrategy<Container>;
  detail::ContainerHelper<Container, Strategy> helper{Strategy()};

  return [=](const Random &random, int size) {
    return helper.generate(random, size, gens...);
  };
}

这是travis build log。

从日志中可以看出我们正在使用gcc 4.8.4来构建这个模块。这似乎支持参数包。

Configuring rapidcheck...

-- The C compiler identification is GNU 4.8.4

-- The CXX compiler identification is GNU 4.8.4

-- Check for working C compiler: /usr/bin/cc

-- Check for working C compiler: /usr/bin/cc -- works

-- Detecting C compiler ABI info

-- Detecting C compiler ABI info - done

-- Detecting C compile features

-- Detecting C compile features - done

-- Check for working CXX compiler: /usr/bin/c++

-- Check for working CXX compiler: /usr/bin/c++ -- works

-- Detecting CXX compiler ABI info

-- Detecting CXX compiler ABI info - done

-- Detecting CXX compile features

-- Detecting CXX compile features - done

-- Configuring done

-- Generating done

所以我不确定为什么这个版本使用gcc失败了。