std::atomic<> for double

[niXman <i dot nixman at gmail dot com>]

Hello!

where is a code that compiles and works as expected:
#include <atomic>
#include <iostream>

int main() {
   std::atomic<int> i(0);
   i += 3;

   std::cout << i << std::endl;
}
http://liveworkspace.org/code/eb92d1706687414dd3f49976584ff337

now change it to type double:
#include <atomic>
#include <iostream>

int main() {
   std::atomic<double> i(0);
   i += 3.14;

   std::cout << i << std::endl;
}
http://liveworkspace.org/code/555191936a23b06352220ff11b1e33df

and get the following error:
> source.cpp: In function 'int main()':
> source.cpp:6:9: error: no match for 'operator+=' in 'i += 3.1400000000000001e+0'

therefore, I have two questions:
1. Ñan double be actually an atomic type?
2. how is supposed to use atomic <double> by standard?


Thanks!

-- 
Regards,
 niXman