Trying to build Slicer in a long path build directory, the build fails when it comes turn to configure ITK. Then it snowballs from there. I guess we need to add extra logic to this check to handle the possibility of longer paths which now exists in Windows.
50> CMake Error at CMakeLists.txt:30 (message):
50> ITK source code directory path length is too long (65 > 50).Please move the
50> ITK source code directory to a directory with a shorter path.
50>
50>
50> -- Configuring incomplete, errors occurred!
50> See also "C:/Dev/Slicer-buildVS2015x64-super-long-path-without-spaces/ITKv4-build/CMakeFiles/CMakeOutput.log".