title: CMake imported library behaviour
body: <p>I've a strange problem with CMake.</p>
  <p>I'm importing Curl into my project, so I write for you a simplified summary of my CMakeLists.txt file.</p>
  <blockquote>
  <p>ADD_LIBRARY (libcurl <strong>SHARED</strong> IMPORTED)</p>
  <p>SET_PROPERTY(TARGET libcurl PROPERTY IMPORTED_LOCATION
  ../lib/libcurl.lib)</p>
  </blockquote>
  <p>When I run CMake it generates the project files for MS VC++ (also for Linux). Then into the project file I find a wrong reference to curl library (<strong>libcurl-NOTFOUND</strong>)!</p>
  <p>If I change my code into static import:</p>
  <blockquote>
  <p>ADD_LIBRARY (libcurl <strong>STATIC</strong> IMPORTED)</p>
  <p>SET_PROPERTY(TARGET libcurl PROPERTY IMPORTED_LOCATION
  ../lib/libcurl.lib)</p>
  </blockquote>
  <p>I find the right reference to ../lib/libcurl.lib.</p>
  <p>Do you have any idea why this happens?</p>
  <p>Thank you very much!</p>