# CMP0107

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. Use the `cmake_policy()` command to set it to `OLD` or `NEW` explicitly. Unlike many policies, CMake version 3.19.4 does not warn when this policy is not set and simply uses `OLD` behavior.

Note

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