Explicitly enable or disable the warning when CMake Policy CMP<NNNN> is not set. This is meaningful only for the few policies that do not warn by default:

  • CMAKE_POLICY_WARNING_CMP0025 controls the warning for policy CMP0025.

  • CMAKE_POLICY_WARNING_CMP0047 controls the warning for policy CMP0047.

This variable should not be set by a project in CMake code. Project developers running CMake may set this variable in their cache to enable the warning (e.g. -DCMAKE_POLICY_WARNING_CMP<NNNN>=ON). Alternatively, running cmake(1) with the --debug-output or --trace option will also enable the warning.