NUC972 交叉编译出错，不支持future？_问答

请问大神，为什么用交叉编译工具编译会报这个错误呢？不是支持c++11的吗？
源码：
// future example
#include          // std::cout
#include             // std::async, std::future
#include             // std::chrono::milliseconds

// a non-optimized way of checking for prime numbers:
bool
is_prime(int x)
{
for (int i = 2; i < x; ++i)
      if (x % i == 0)
         return false;
return true;
}

int main()
{
// call function asynchronously:
std::future < bool > fut = std::async(is_prime, 444444443);

// do something while waiting for function to set future:
std::cout << "checking, please wait";
std::chrono::milliseconds span(100);
while (fut.wait_for(span) == std::future_status::timeout)
      std::cout << '.';

bool x = fut.get();       // retrieve return value

std::cout << "\n444444443 " << (x ? "is" : "is not") << " prime.\n";

return 0;
}
编译选项：arm-linux-g++ future.cpp -lpthread -std=c++11
出错内容：
future.cpp: In function ‘int main()’:
future.cpp:19:26: error: variable ‘std::future fut’ has initializer but incomplete type
   std::future < bool > fut = std::async(is_prime, 444444443);
                        ^
future.cpp:19:62: error: invalid use of incomplete type ‘class std::future’
   std::future < bool > fut = std::async(is_prime, 444444443);
                                                            ^
In file included from future.cpp:3:0:
/usr/local/arm_linux_4.8/arm-nuvoton-linux-uclibceabi/include/c++/4.8.4/future:113:11: error: declaration of ‘class std::future’
   class future;
         ^

NUC972 交叉编译出错，不支持future？

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