New in version 3.18.

It is not allowed to create an ALIAS target with the same name as an another target.

In CMake 3.17 and below, an ALIAS target can overwrite silently an existing target with the same name.

The OLD behavior for this policy is to allow target overwrite.

The NEW behavior of this policy is to prevent target overwriting.

This policy was introduced in CMake version 3.17. It may be set by cmake_policy() or cmake_minimum_required(). If it is not set, CMake does not warn, and uses OLD behavior.


The OLD behavior of a policy is deprecated by definition and may be removed in a future version of CMake.