| CMP0102 |
| ------- |
| |
| .. versionadded:: 3.17 |
| |
| The :command:`mark_as_advanced` command no longer creates a cache entry if one |
| does not already exist. |
| |
| In CMake 3.16 and below, if a variable was not defined at all or just defined |
| locally, the :command:`mark_as_advanced` command would create a new cache |
| entry with an ``UNINITIALIZED`` type and no value. When a :command:`find_path` |
| (or other similar ``find_`` command) would next run, it would find this |
| undefined cache entry and set it up with an empty string value. This process |
| would end up deleting the local variable in the process (due to the way the |
| cache works), effectively clearing any stored ``find_`` results that were only |
| available in the local scope. |
| |
| The ``OLD`` behavior for this policy is to create the empty cache definition. |
| The ``NEW`` behavior of this policy is to ignore variables which do not |
| already exist in the cache. |
| |
| .. |INTRODUCED_IN_CMAKE_VERSION| replace:: 3.17 |
| .. |WARNS_OR_DOES_NOT_WARN| replace:: does *not* warn by default |
| .. include:: STANDARD_ADVICE.txt |
| |
| See documentation of the :variable:`CMAKE_POLICY_WARNING_CMP0102 |
| <CMAKE_POLICY_WARNING_CMP<NNNN>>` variable to control the warning. |
| |
| .. include:: DEPRECATED.txt |
