title: Setting a cross-compiler file using the CMake GUI
body: <p>I'm trying set-up my cross-compile build using CMake. So far I'm setting the cross compiler file calling CMake like this from the command line:</p>
  
  <pre><code>#Call cmake with the given options
  cmake -D CMAKE_TOOLCHAIN_FILE=$cross_cmp_file \
        -D BUILD_TESTS:BOOLEAN=$build_test \
        ../src 
  </code></pre>
  
  <p>This works just fine.</p>
  
  <p>Now I'm trying to set the CMAKE_TOOLCHAIN_FILE variable from the GUI by adding:</p>
  
  <pre><code>#CMAKE cross compiler file
  set(CMAKE_TOOLCHAIN_FILE "Toolchain file" CACHE FILEPATH "../arm-crosscompile.cmake")
  </code></pre>
  
  <p>To my CMakeLists.txt.</p>
  
  <p>This actually shows the variable in the GUI but when I press the "Configure"  button, the c++ compiler that appear in the CMAKE_CXX_COMPILER variable is the one by default and not the one specified in the toolchain file.</p>
  
  <p>How can I set the toolchain file from the Cmake-GUI?</p>