# CMP0002

Logical target names must be globally unique.

Targets names created with `add_executable()`, `add_library()`, or `add_custom_target()` are logical build target names. Logical target names must be globally unique because:

    - Unique names may be referenced unambiguously both in CMake
      code and on make tool command lines.
    - Logical names are used by Xcode and VS IDE generators
      to produce meaningful project names for the targets.

The logical name of executable and library targets does not have to correspond to the physical file names built. Consider using the `OUTPUT_NAME` target property to create two targets with the same physical name while keeping logical names distinct. Custom targets must simply have globally unique names (unless one uses the global property `ALLOW_DUPLICATE_CUSTOM_TARGETS` with a Makefiles generator).

This policy was introduced in CMake version 2.6.0. CMake version 3.18.0-rc3 warns when the policy is not set and uses `OLD` behavior. Use the `cmake_policy()` command to set it to `OLD` or `NEW` explicitly.

Note

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