| CMP0028 |
| ------- |
| |
| Double colon in target name means ``ALIAS`` or ``IMPORTED`` target. |
| |
| CMake 2.8.12 and lower allowed the use of targets and files with double |
| colons in :command:`target_link_libraries`, with some buildsystem generators. |
| |
| The use of double-colons is a common pattern used to namespace ``IMPORTED`` |
| targets and ``ALIAS`` targets. When computing the link dependencies of |
| a target, the name of each dependency could either be a target, or a file |
| on disk. Previously, if a target was not found with a matching name, the name |
| was considered to refer to a file on disk. This can lead to confusing error |
| messages if there is a typo in what should be a target name. |
| |
| The ``OLD`` behavior for this policy is to search for targets, then files on |
| disk, even if the search term contains double-colons. The ``NEW`` behavior |
| for this policy is to issue a ``FATAL_ERROR`` if a link dependency contains |
| double-colons but is not an ``IMPORTED`` target or an ``ALIAS`` target. |
| |
| This policy was introduced in CMake version 3.0. CMake version |
| |release| warns when the policy is not set and uses ``OLD`` behavior. Use |
| the :command:`cmake_policy` command to set it to ``OLD`` or ``NEW`` explicitly. |
| |
| .. include:: DEPRECATED.txt |
