title: Why including atomic - gives errors
body: <p>I'm using g++ (gcc) version 4.9.2 under ubuntu 64 bit 14.04.
  I'm trying to compile the following simple code:</p>
  
  <pre><code>#include &lt;iostream&gt;
  #include &lt;atomic&gt;
  using namespace std;
  
  int main() {
      cout &lt;&lt; "!!!Hello World!!!" &lt;&lt; endl; // prints !!!Hello World!!!
      return 0;
  }
  </code></pre>
  
  <p>And get the following errors:</p>
  
  <pre><code>/usr/include/c++/4.9/atomic:385:56: error: ‘noexcept’ does not name a type
        memory_order __m = memory_order_seq_cst) volatile noexcept
                                                          ^
  /usr/include/c++/4.9/atomic:389:53: error: expected ‘;’ at end of member declaration
         load(memory_order __m = memory_order_seq_cst) const noexcept
                                                       ^
  /usr/include/c++/4.9/atomic:389:59: error: ‘noexcept’ does not name a type
         load(memory_order __m = memory_order_seq_cst) const noexcept
                                                             ^
  /usr/include/c++/4.9/atomic:393:59: error: expected ‘;’ at end of member declaration
         load(memory_order __m = memory_order_seq_cst) const volatile noexcept
                                                             ^
  /usr/include/c++/4.9/atomic:393:68: error: ‘noexcept’ does not name a type
         load(memory_order __m = memory_order_seq_cst) const volatile noexcept
                                                                      ^
  /usr/include/c++/4.9/atomic:398:48: error: expected ‘;’ at end of member declaration
           memory_order __m = memory_order_seq_cst) noexcept
                                                  ^
  /usr/include/c++/4.9/atomic:398:50: error: ‘noexcept’ does not name a type
           memory_order __m = memory_order_seq_cst) noexcept
  </code></pre>
  
  <p>Why cant I compile this simple example ?</p>