title: Dumping memory layout of C++ object does not work in clang
body: <p>I have read an article about <a href="https://eli.thegreenplace.net/2012/12/17/dumping-a-c-objects-memory-layout-with-clang/" rel="nofollow noreferrer">dumping a C++ object's memory layout with Clang</a> and now I am trying to play with this feature. I have create two classes:</p>
  
  <pre><code>// simple.cpp
  struct Base
  {
      int value;
  };
  
  struct Derived : Base
  {
      int count;
  };
  
  int main(int argc, char* argv[])
  {
      return 0;
  }
  </code></pre>
  
  <p>and run the following command:</p>
  
  <pre><code>$ clang -cc1 -fdump-record-layouts-simple simple.cpp
  </code></pre>
  
  <p>and get nothing. clang version is:</p>
  
  <pre><code>$ clang++ -dumpversion
  4.2.1
  </code></pre>
  
  <p>If I run the following command:</p>
  
  <pre><code>$ clang -cc1 --help
  </code></pre>
  
  <p>and among a lot information I can find this one:</p>
  
  <pre><code>...
    -fdump-record-layouts-simple
                            Dump record layout information in a simple form used for testing
    -fdump-record-layouts   Dump record layout information
    -fdump-vtable-layouts   Dump the layouts of all vtables that will be emitted in a translation unit
  ...
  </code></pre>
  
  <p>What I do wrong?</p>