title: An exported aliases symbol doesn't exist in PDB file (RegisterClipboardFormat has RegisterWindowMessage internal name)
body: <p>I'm trying to set a breakpoint in user32!RegisterClipboardFormat
  Evidently, this function is exported (link /dump /exports - it is right there). Before downloading the PDB file from the Microsoft symbol server, I'm able to find this function:</p>
  
  <pre><code>0:001&gt; lm m user32
  start    end
  76eb0000 76fcf000   USER32     (export symbols)       c:\Windows\system32\USER32.dll
  
  0:001&gt; x user32!RegisterClipboardFormat*
  76ec4eae USER32!RegisterClipboardFormatA (&lt;no parameter info&gt;)
  76ec6ffa USER32!RegisterClipboardFormatW (&lt;no parameter info&gt;)
  </code></pre>
  
  <p>No problems. I'm able to 'bu' any of these functions. But when I download the PDB symbols from the Microsoft PDB server:</p>
  
  <pre><code>0:001&gt; 
  start    end        module name
  76d50000 76e6f000   USER32     (pdb symbols)          c:\symbols\user32.pdb\561A146545614951BDB6282F2E3522F72\user32.pdb
  
  0:000&gt; x user32!RegisterClipboardFormat
  </code></pre>
  
  <p>WinDBG cannot find the symbols. However, it can find RegisterWindowMesssage:</p>
  
  <pre><code>0:000&gt; x user32!RegisterWindowMessage*
  76d64eae          USER32!RegisterWindowMessageA = &lt;no type information&gt;
  76d66ffa          USER32!RegisterWindowMessageW = &lt;no type information&gt;
  </code></pre>
  
  <p>Note that the functions have the same addresses (This is on Windows 8. Not sure about previous versions). This is probably achieved by the optimizer or in the DEF file (func1=func2 in the EXPORT section). 'link /dump /exports' shows RegisterWindowMessage and RegisterClipboardFormat have the same RVA.</p>
  
  <p>Problem is that I spent way too much time on this. So my questions are:</p>
  
  <ol>
  <li>Is there is an easy way, from within WinDBG to find out missing aliased export symbols. </li>
  <li>Say I want to break only on RegisterClipboardFormatW. If I recall correctly, there should be a JMP instruction somewhere (in the calling module import table). How do I find that symbol? Is there a way to find this entry in all calling modules?</li>
  </ol>