CMP0089 ------- Compiler id for IBM Clang-based XL compilers is now ``XLClang``. CMake 3.15 and above recognize that IBM's Clang-based XL compilers that define ``__ibmxl__`` are a new front-end distinct from ``xlc`` with a different command line and set of capabilities. CMake now prefers to present this to projects by setting the :variable:`CMAKE__COMPILER_ID` variable to ``XLClang`` instead of ``XL``. However, existing projects may assume the compiler id for Clang-based XL is just ``XL`` as it was in CMake versions prior to 3.15. Therefore this policy determines for Clang-based XL compilers which compiler id to report in the :variable:`CMAKE__COMPILER_ID` variable after language ```` is enabled by the :command:`project` or :command:`enable_language` command. The policy must be set prior to the invocation of either command. The ``OLD`` behavior for this policy is to use compiler id ``XL``. The ``NEW`` behavior for this policy is to use compiler id ``XLClang``. This policy was introduced in CMake version 3.15. Use the :command:`cmake_policy` command to set this policy to ``OLD`` or ``NEW`` explicitly. Unlike most policies, CMake version |release| does *not* warn by default when this policy is not set and simply uses ``OLD`` behavior. See documentation of the :variable:`CMAKE_POLICY_WARNING_CMP0089 >` variable to control the warning. .. include:: DEPRECATED.txt