CMake Error in CMakeLists\.txt:
  Target "somelib" has source files which vary by configuration\.  This is not
  supported by the "[^"]+" generator\.

  Config "Debug":

    .*/Tests/RunCMake/target_sources/empty_1\.cpp
    .*/Tests/RunCMake/target_sources/empty_2\.cpp

  Config "Release":

    .*/Tests/RunCMake/target_sources/empty_1\.cpp
