title: When is anonymous namespace data initialized?
body: <p>I have been using anonymous namespaces to store local data and functions and wanted to know when the data is initialized?  Is it when the application starts in the same way as static data or is it compiler dependent?  For example:</p>
  
  <pre><code>// foo.cpp
  #include "foo.h"
  
  namespace {
  
  const int SOME_VALUE = 42;
  
  }
  
  void foo::SomeFunc(int n)
  {
      if (n == SOME_VALUE)
      {
          ...
      }
  }
  </code></pre>
  
  <p>The question arises out of making some code thread-safe.  In the above example I need to be certain that <code>SOME_VALUE</code> is initialized before SomeFunc is called for the first time.</p>