title: Clion: Error in debug but not in release mode
body: <p>my problem is that if I compile my project with "Debug" configuration in CLion it returns this error:</p>
  
  <pre><code>/usr/include/c++/6/parallel/tags.h: In member function ‘__gnu_parallel::_ThreadIndex __gnu_parallel::parallel_tag::__get_num_threads()’:
  /usr/include/c++/6/parallel/tags.h:66:38: error: ‘omp_get_max_threads’ was not declared in this scope
             return omp_get_max_threads();
  </code></pre>
  
  <p>But if I run the same code with "Release" configuration it works normal. Does somebody knows how to fix this error or why I can run it only by using the release configuration?</p>