title: VSCode C/C++ Intellisense issue: Undefined identifiers (Linux, Manjaro)
body: <ul>
  <li>OS: Manjaro 18.1.5</li>
  <li>VS Code (OSS): 1.41.1</li>
  <li>C/C++ Extension: 0.26.3</li>
  </ul>
  
  <p>Hi,</p>
  
  <p>I have an issue using VS Code with the C/C++ extension. Some identifiers are not recognized by Intellisense, although my includePath in <code>c_cpp_properties.json</code> seems fine.</p>
  
  <p>For instance here I am trying to display the current time with <code>time()</code> from the <code>ctime</code> library. VS Code tells me that the <code>time</code> identifier is undefined:</p>
  
  <pre><code>#include &lt;iostream&gt;
  #include &lt;ctime&gt;
  
  using namespace std;
  
  int main()
  {
      cout &lt;&lt; time(nullptr) &lt;&lt; endl; //--&gt; "time" identifier is undefined
  }
  </code></pre>
  
  <p>Here is my <code>c_cpp_properties.json</code> file:</p>
  
  <pre><code>{
      "configurations": [
          {
              "name": "Linux",
              "includePath": [
                  "${workspaceFolder}/**",
                  "/usr/include/linux",
                  "/usr/include/c++/9.2.0/tr1"
              ],
              "defines": [],
              "compilerPath": "/usr/bin/gcc",
              "cStandard": "c11",
              "cppStandard": "c++17",
              "intelliSenseMode": "gcc-x64"
          }
      ],
      "version": 4
  }
  </code></pre>
  
  <p>There is a <code>ctime</code> file at <code>/usr/include/c++/9.2.0/tr1/</code> as well as at <code>/usr/include/c++/9.2.0/</code> but changing the includePath to the latter doesn't change anything.</p>
  
  <p>I know that many have similar issues but I couldn't find a solution that works for me, I don't know if it's specific to my linux distribution or whatsoever (see above for OS/Apps infos).</p>
  
  <p>Thanks for your help,</p>
  
  <p>FB.</p>