title: Why CMake custom target won't be built even if dependency was changed
body: <p>My <code>CMakeLists.txt</code> files parses some text files where library dependencies are specified by developers. Those files, let's call them <code>linkfile.txt</code>, are simple text files listing libraries to be linked with, this makes it easy to developers not familiar with <code>CMake</code> to extend a library dependency list.</p>
  
  <p>I use Visual Studio 2015 generator.</p>
  
  <p>Now, when one modifies this text file, Visual Studio does not autoamtically runs CMake to update the solution while you request it to build (it does when you modified an included cmake file or a <code>CMakeLists.txt</code> file).</p>
  
  <p>Is there a way to tell <code>CMake</code> that some extra files may invalidate the solution and require <code>CMake</code> to be ran again?</p>
  
  <p>If not, I already have a custom target to let user manually run CMake when needed:</p>
  
  <pre><code>ADD_CUSTOM_TARGET( RECONFIGURE COMMAND ${CMAKE_COMMAND} ${CMAKE_BINARY_DIR} )
  </code></pre>
  
  <p>So I could reuse that. But, if I specify <code>DEPENDS [path_to]/linkfile.txt</code> parameter to <code>ADD_CUSTOM_TARGET</code>, <code>RECONFIGURE</code> does not get automatically generated when I request to generate the solution after <code>linkfile.txt</code> was modified (while it does if a cmake file or <code>CMakeLists.txt</code> file was modified).</p>