INCLUDE_DIRECTORIES ------------------- List of preprocessor include file search directories. This property holds a :ref:`;-list ` of paths and will be added to the list of include directories when this source file builds. These directories will take precedence over directories defined at target level except for :generator:`Xcode` generator due to technical limitations. Relative paths should not be added to this property directly. Contents of ``INCLUDE_DIRECTORIES`` may use "generator expressions" with the syntax ``$<...>``. See the :manual:`cmake-generator-expressions(7)` manual for available expressions. However, :generator:`Xcode` does not support per-config per-source settings, so expressions that depend on the build configuration are not allowed with that generator.