title: How To Add <math.h> header in CLion
body: <p>I'm New to CLion. I have created a project which name is <em>test12</em> and which file name is <em>avs.c</em>.</p>
  
  <p>I'm Getting an Error of type <code>Undefined reference 'sqrt'</code></p>
  
  <p><em>CMakeListsta.txt</em> is :</p>
  
  <pre><code>cmake_minimum_required(VERSION 3.13)
  project (test12 C)
  set(CMAKE_C_STANDARD 99)
  add_executable(test12 avs.c) 
  </code></pre>
  
  <p>What changes should I do to make CMAKELISTS use <em>math.h</em> header in <em>CLion</em>?</p>