elseif(DEFINED CMAKE_TOOLCHAIN_FILE AND NOT CMAKE_TOOLCHAIN_FILE MATCHES ".+/vcpkg/scripts/buildsystems/vcpkg.cmake$")
message(STATUS "CMAKE_TOOLCHAIN_FILE is already set to '${CMAKE_TOOLCHAIN_FILE}', replace it with the vcpkg one and set VCPKG_CHAINLOAD_TOOLCHAIN_FILE to original CMAKE_TOOLCHAIN_FILE")