^CMake Deprecation Warning at CMP0051-OLD.cmake:2 \(cmake_policy\): The OLD behavior for policy CMP0051 will be removed from a future version of CMake. The cmake-policies\(7\) manual explains that the OLD behaviors of all policies are deprecated and that a policy should be set to OLD only under specific short-term circumstances. Projects should be ported to the NEW behavior and not rely on setting a policy to OLD. Call Stack \(most recent call first\): CMakeLists\.txt:[0-9]+ \(include\) + Sources: "empty.cpp"$