target_link_libraries¶
Link a target to given libraries.
target_link_libraries(<target> [item1 [item2 [...]]]
[[debug|optimized|general] <item>] ...)
Specify libraries or flags to use when linking a given target. The
named <target>
must have been created in the current directory by a
command such as add_executable()
or add_library()
. The
remaining arguments specify library names or flags. Repeated calls for
the same <target>
append items in the order called.
If a library name matches that of another target in the project a
dependency will automatically be added in the build system to make sure
the library being linked is up-to-date before the target links. Item names
starting with -
, but not -l
or -framework
, are treated as
linker flags. Note that such flags will be treated like any other library
link item for purposes of transitive dependencies, so they are generally
safe to specify only as private link items that will not propagate to
dependents of <target>
.
A debug
, optimized
, or general
keyword indicates that the
library immediately following it is to be used only for the
corresponding build configuration. The debug
keyword corresponds to
the Debug configuration (or to configurations named in the
DEBUG_CONFIGURATIONS
global property if it is set). The
optimized
keyword corresponds to all other configurations. The
general
keyword corresponds to all configurations, and is purely
optional (assumed if omitted). Higher granularity may be achieved for
per-configuration rules by creating and linking to
IMPORTED library targets.
Library dependencies are transitive by default with this signature.
When this target is linked into another target then the libraries
linked to this target will appear on the link line for the other
target too. This transitive “link interface” is stored in the
INTERFACE_LINK_LIBRARIES
target property and may be overridden
by setting the property directly. When CMP0022
is not set to
NEW
, transitive linking is built in but may be overridden by the
LINK_INTERFACE_LIBRARIES
property. Calls to other signatures
of this command may set the property making any libraries linked
exclusively by this signature private.
CMake will also propagate usage requirements
from linked library targets. Usage requirements of dependencies affect
compilation of sources in the <target>
.
If an <item>
is a library in a Mac OX framework, the Headers
directory of the framework will also be processed as a
usage requirement. This has the same
effect as passing the framework directory as an include directory.
target_link_libraries(<target>
<PRIVATE|PUBLIC|INTERFACE> <lib> ...
[<PRIVATE|PUBLIC|INTERFACE> <lib> ... ] ...])
The PUBLIC
, PRIVATE
and INTERFACE
keywords can be used to
specify both the link dependencies and the link interface in one command.
Libraries and targets following PUBLIC
are linked to, and are made
part of the link interface. Libraries and targets following PRIVATE
are linked to, but are not made part of the link interface. Libraries
following INTERFACE
are appended to the link interface and are not
used for linking <target>
.
target_link_libraries(<target> LINK_INTERFACE_LIBRARIES
[[debug|optimized|general] <lib>] ...)
The LINK_INTERFACE_LIBRARIES
mode appends the libraries to the
INTERFACE_LINK_LIBRARIES
target property instead of using them
for linking. If policy CMP0022
is not NEW
, then this mode
also appends libraries to the LINK_INTERFACE_LIBRARIES
and its
per-configuration equivalent.
This signature is for compatibility only. Prefer the INTERFACE
mode
instead.
Libraries specified as debug
are wrapped in a generator expression to
correspond to debug builds. If policy CMP0022
is
not NEW
, the libraries are also appended to the
LINK_INTERFACE_LIBRARIES_DEBUG
property (or to the properties corresponding to configurations listed in
the DEBUG_CONFIGURATIONS
global property if it is set).
Libraries specified as optimized
are appended to the
INTERFACE_LINK_LIBRARIES
property. If policy CMP0022
is not NEW
, they are also appended to the
LINK_INTERFACE_LIBRARIES
property. Libraries specified as
general
(or without any keyword) are treated as if specified for both
debug
and optimized
.
target_link_libraries(<target>
<LINK_PRIVATE|LINK_PUBLIC>
[[debug|optimized|general] <lib>] ...
[<LINK_PRIVATE|LINK_PUBLIC>
[[debug|optimized|general] <lib>] ...])
The LINK_PUBLIC
and LINK_PRIVATE
modes can be used to specify both
the link dependencies and the link interface in one command.
This signature is for compatibility only. Prefer the PUBLIC
or
PRIVATE
keywords instead.
Libraries and targets following LINK_PUBLIC
are linked to, and are
made part of the INTERFACE_LINK_LIBRARIES
. If policy
CMP0022
is not NEW
, they are also made part of the
LINK_INTERFACE_LIBRARIES
. Libraries and targets following
LINK_PRIVATE
are linked to, but are not made part of the
INTERFACE_LINK_LIBRARIES
(or LINK_INTERFACE_LIBRARIES
).
The library dependency graph is normally acyclic (a DAG), but in the case
of mutually-dependent STATIC
libraries CMake allows the graph to
contain cycles (strongly connected components). When another target links
to one of the libraries, CMake repeats the entire connected component.
For example, the code
add_library(A STATIC a.c)
add_library(B STATIC b.c)
target_link_libraries(A B)
target_link_libraries(B A)
add_executable(main main.c)
target_link_libraries(main A)
links main
to A B A B
. While one repetition is usually
sufficient, pathological object file and symbol arrangements can require
more. One may handle such cases by manually repeating the component in
the last target_link_libraries
call. However, if two archives are
really so interdependent they should probably be combined into a single
archive.
Arguments to target_link_libraries may use “generator expressions”
with the syntax $<...>
. Note however, that generator expressions
will not be used in OLD handling of CMP0003
or CMP0004
.
See the cmake-generator-expressions(7)
manual for available
expressions. See the cmake-buildsystem(7)
manual for more on
defining buildsystem properties.