1INCLUDE_DIRECTORIES 2------------------- 3 4List of preprocessor include file search directories. 5 6This property specifies the list of directories given so far to the 7:command:`include_directories` command. 8 9This property is used to populate the :prop_tgt:`INCLUDE_DIRECTORIES` 10target property, which is used by the generators to set the include 11directories for the compiler. 12 13In addition to accepting values from that command, values may be set 14directly on any directory using the :command:`set_property` command, and can be 15set on the current directory using the :command:`set_directory_properties` 16command. A directory gets its initial value from its parent directory if it has 17one. The initial value of the :prop_tgt:`INCLUDE_DIRECTORIES` target property 18comes from the value of this property. Both directory and target property 19values are adjusted by calls to the :command:`include_directories` command. 20Calls to :command:`set_property` or :command:`set_directory_properties`, 21however, will update the directory property value without updating target 22property values. Therefore direct property updates must be made before 23calls to :command:`add_executable` or :command:`add_library` for targets 24they are meant to affect. 25 26The target property values are used by the generators to set the 27include paths for the compiler. 28 29Contents of ``INCLUDE_DIRECTORIES`` may use "generator expressions" with 30the syntax ``$<...>``. See the :manual:`cmake-generator-expressions(7)` 31manual for available expressions. See the :manual:`cmake-buildsystem(7)` 32manual for more on defining buildsystem properties. 33