CMake Warning \(dev\) at dir1/CMakeLists.txt:5 \(target_compile_definitions\):
  Policy CMP0044 is not set: Case sensitive <LANG>_COMPILER_ID generator
  expressions.  Run "cmake --help-policy CMP0044" for policy details.  Use
  the cmake_policy command to set the policy and suppress this warning.
This warning is for project developers.  Use -Wno-dev to suppress it.