title: Can't compile c++ program using gcc on Mac after updating to Monterey
body: <p>*Update:
  Regarding the similar question <a href="https://stackoverflow.com/questions/26185978/macos-wchar-h-file-not-found">macos-wchar-h-file-not-found</a>, the command line tool switch(xcode-select --install) doesn't exist anymore.</p>
  <p>I am running on macOS Monterey system and I am trying to compile a simple hello world .cpp file using the g++-11 commend (I installed gcc using homebrew), I am getting the following error:</p>
  <pre class="lang-none prettyprint-override"><code>/usr/local/Cellar/gcc/11.2.0_3/include/c++/11/cwchar:44:10: fatal error: wchar.h: No such file or directory
     44 | #include &lt;wchar.h&gt;
        |          ^~~~~~~~~
  </code></pre>
  <p>I tried two compile commands:</p>
  <pre><code>g++-11 -c hello.cpp -o hell.o 
  
  g++-11 -std=c++11 -c hello.cpp -o hell.o
  </code></pre>
  <p>Here is the file I am trying to compile:</p>
  <pre><code>//
  //  main.cpp
  //  Test
  //
  //  Created by Jiali Zhu on 1/9/22.
  //
  
  #include &lt;iostream&gt;
  
  int main(int argc, const char * argv[]) {
      // insert code here...
      std::cout &lt;&lt; &quot;Hello, World!\n&quot;;
      return 0;
  }
  </code></pre>