CMake attempts to provide some values for the following variables: CMAKE_CXX_FLAGS CMAKE_CXX_FLAGS_DEBUG -g CMAKE_CXX_FLAGS_MINSIZEREL -O3 CMAKE_CXX_FLAGS_RELEASE -O2 CMAKE_CXX_FLAGS_RELWITHDEBINFO -O2 How can I change the default and allow the user to make changes the persists across configuation? Thanks, James