Add include directories to the build.
include_directories([AFTER|BEFORE] [SYSTEM] dir1 [dir2 ...])
Add the given directories to those the compiler uses to search for include files. Relative paths are interpreted as relative to the current source directory.
The include directories are added to the
directory property for the current
CMakeLists file. They are also
added to the
INCLUDE_DIRECTORIES target property for each
target in the current
CMakeLists file. The target property values
are the ones used by the generators.
By default the directories specified are appended onto the current list of
directories. This default behavior can be changed by setting
ON. By using
BEFORE explicitly, you can select between appending and
prepending, independent of the default.
SYSTEM option is given, the compiler will be told the
directories are meant as system include directories on some platforms.
Signalling this setting might achieve effects such as the compiler
skipping warnings, or these fixed-install system files not being
considered in dependency calculations - see compiler docs.
include_directories may use “generator expressions” with
the syntax “$<...>”. See the
manual for available expressions. See the
manual for more on defining buildsystem properties.