# CMP0022

INTERFACE_LINK_LIBRARIES defines the link interface.

CMake 2.8.11 constructed the ‘link interface’ of a target from properties matching `(IMPORTED_)?LINK_INTERFACE_LIBRARIES(_<CONFIG>)?`. The modern way to specify config-sensitive content is to use generator expressions and the `IMPORTED_` prefix makes uniform processing of the link interface with generator expressions impossible. The INTERFACE_LINK_LIBRARIES target property was introduced as a replacement in CMake 2.8.12. This new property is named consistently with the INTERFACE_COMPILE_DEFINITIONS, INTERFACE_INCLUDE_DIRECTORIES and INTERFACE_COMPILE_OPTIONS properties. For in-build targets, CMake will use the INTERFACE_LINK_LIBRARIES property as the source of the link interface only if policy CMP0022 is NEW. When exporting a target which has this policy set to NEW, only the INTERFACE_LINK_LIBRARIES property will be processed and generated for the IMPORTED target by default. A new option to the install(EXPORT) and export commands allows export of the old-style properties for compatibility with downstream users of CMake versions older than 2.8.12. The target_link_libraries command will no longer populate the properties matching LINK_INTERFACE_LIBRARIES(_<CONFIG>)? if this policy is NEW.

Warning-free future-compatible code which works with CMake 2.8.7 onwards can be written by using the `LINK_PRIVATE` and `LINK_PUBLIC` keywords of `target_link_libraries()`.

The OLD behavior for this policy is to ignore the INTERFACE_LINK_LIBRARIES property for in-build targets. The NEW behavior for this policy is to use the INTERFACE_LINK_LIBRARIES property for in-build targets, and ignore the old properties matching `(IMPORTED_)?LINK_INTERFACE_LIBRARIES(_<CONFIG>)?`.

This policy was introduced in CMake version 2.8.12. CMake version 3.9.1 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.