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 directories are added to the LINK_DIRECTORIES
directory property for the current CMakeLists.txt
file, converting relative paths to absolute as needed. The command will apply only to targets created after it is called.
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.
Arguments to link_directories
may use “generator expressions” with the syntax “$<…>”. See the cmake-generator-expressions(7)
manual for available expressions. See the cmake-buildsystem(7)
manual for more on defining buildsystem properties.
Note
This command is rarely necessary and should be avoided where there are other choices. Prefer to pass full absolute paths to libraries where possible, since this ensures the correct library will always be linked. The find_library()
command provides the full path, which can generally be used directly in calls to target_link_libraries()
. Situations where a library search path may be needed include:
- Project generators like Xcode where the user can switch target architecture at build time, but a full path to a library cannot be used because it only provides one architecture (i.e. it is not a universal binary).
- Libraries may themselves have other private library dependencies that expect to be found via
RPATH
mechanisms, but some linkers are not able to fully decode those paths (e.g. due to the presence of things like$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.
© 2000–2020 Kitware, Inc. and Contributors
Licensed under the BSD 3-clause License.
https://cmake.org/cmake/help/v3.17/command/link_directories.html