link_directories¶
Add directories in which the linker will look for libraries.
link_directories([AFTER|BEFORE] directory1 [directory2 ...])
Adds the paths in which the linker should search for libraries.
Relative paths given to this command are interpreted as relative to
the current source directory, see CMP0015.
The command will apply only to targets created after it is called.
New in version 3.13: The directories are added to the LINK_DIRECTORIES directory
property for the current CMakeLists.txt file, converting relative
paths to absolute as needed. See the cmake-buildsystem(7)
manual for more on defining buildsystem properties.
New in version 3.13: By default the directories specified are appended onto the current list of
directories. This default behavior can be changed by setting
CMAKE_LINK_DIRECTORIES_BEFORE to ON. By using
AFTER or BEFORE explicitly, you can select between appending and
prepending, independent of the default.
New in version 3.13: Arguments to link_directories may use "generator expressions" with
the syntax "$<...>". See the cmake-generator-expressions(7)
manual for available expressions.
Note
This command is rarely necessary and should be avoided where there are
other choices. Prefer to pass full absolute paths to libraries where
possible, since this ensures the correct library will always be linked.
The find_library() command provides the full path, which can
generally be used directly in calls to target_link_libraries().
Situations where a library search path may be needed include:
Project generators like Xcode where the user can switch target architecture at build time, but a full path to a library cannot be used because it only provides one architecture (i.e. it is not a universal binary).
Libraries may themselves have other private library dependencies that expect to be found via
RPATHmechanisms, but some linkers are not able to fully decode those paths (e.g. due to the presence of things like$ORIGIN).
If a library search path must be provided, prefer to localize the effect
where possible by using the target_link_directories() command
rather than link_directories(). The target-specific command can also
control how the search directories propagate to other dependent targets.