title: CMake Error try_compile pthreads of type executable
body: <pre><code>-- Looking for include file pthread.h
  -- Looking for include file pthread.h - found
  -- Looking for pthread_create
  -- Looking for pthread_create - not found
  -- Looking for pthread_create in pthreads CMake Error at /usr/share/cmake/Modules/CheckLibraryExists.cmake:41 (try_compile):   Only libraries may be used as try_compile IMPORTED LINK_LIBRARIES.  Got   pthreads of type EXECUTABLE. Call Stack (most recent call first):   /usr/share/cmake/Modules/FindThreads.cmake:58 (CHECK_LIBRARY_EXISTS)   tests/app_suite/CMakeLists.txt:58 (find_package)
  
  
  -- Looking for pthread_create in pthreads - not found
  -- Looking for pthread_create in pthread
  -- Looking for pthread_create in pthread - found
  -- Found Threads: TRUE
  </code></pre>
  
  <p>I'm on fedora 18 64-bit.</p>
  
  <pre><code>find_package(Threads REQUIRED)
  target_link_libraries(app_suite_tests ${CMAKE_THREAD_LIBS_INIT})
  </code></pre>
  
  <p>is the code that is creating this. What can I do to prevent CMake from throwing an error here, or how can I get CMake to check the pthreads library over the executable?</p>
  
  <p>Thanks.</p>
  
  <p>Additonal Info:</p>
  
  <pre><code>if(NOT CMAKE_HAVE_THREADS_LIBRARY)
      # Do we have -lpthreads
      CHECK_LIBRARY_EXISTS(pthreads pthread_create "" CMAKE_HAVE_PTHREADS_CREATE)
      if(CMAKE_HAVE_PTHREADS_CREATE)
        set(CMAKE_THREAD_LIBS_INIT "-lpthreads")
        set(CMAKE_HAVE_THREADS_LIBRARY 1)
        set(Threads_FOUND TRUE)
      endif()
  </code></pre>
  
  <p>Is from FindThreads.cmake, and the error is thrown on CHECK_LIBRARY_EXISTS</p>