target_link_options¶
Add options to the link step for an executable, shared library or module library target.
target_link_options(<target> [BEFORE]
<INTERFACE|PUBLIC|PRIVATE> [items1...]
[<INTERFACE|PUBLIC|PRIVATE> [items2...] ...])
The named <target>
must have been created by a command such as
add_executable()
or add_library()
and must not be an
ALIAS target.
This command can be used to add any link options, but alternative commands
exist to add libraries (target_link_libraries()
or
link_libraries()
). See documentation of the
directory
and
target
LINK_OPTIONS
properties.
Note
This command cannot be used to add options for static library targets,
since they do not use a linker. To add archiver or MSVC librarian flags,
see the STATIC_LIBRARY_OPTIONS
target property.
If BEFORE
is specified, the content will be prepended to the property
instead of being appended.
The INTERFACE
, PUBLIC
and PRIVATE
keywords are required to
specify the scope of the following arguments. PRIVATE
and PUBLIC
items will populate the LINK_OPTIONS
property of
<target>
. PUBLIC
and INTERFACE
items will populate the
INTERFACE_LINK_OPTIONS
property of <target>
.
(IMPORTED targets only support INTERFACE
items.)
The following arguments specify link options. Repeated calls for the same
<target>
append items in the order called.
Arguments to target_link_options
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.
The final set of compile or link options used for a target is constructed by
accumulating options from the current target and the usage requirements of
its dependencies. The set of options is de-duplicated to avoid repetition.
While beneficial for individual options, the de-duplication step can break
up option groups. For example, -D A -D B
becomes -D A B
. One may
specify a group of options using shell-like quoting along with a SHELL:
prefix. The SHELL:
prefix is dropped, and the rest of the option string
is parsed using the separate_arguments()
UNIX_COMMAND
mode.
For example, "SHELL:-D A" "SHELL:-D B"
becomes -D A -D B
.
To pass options to the linker tool, each compiler driver has its own syntax.
The LINKER:
prefix and ,
separator can be used to specify, in a portable
way, options to pass to the linker tool. LINKER:
is replaced by the
appropriate driver option and ,
by the appropriate driver separator.
The driver prefix and driver separator are given by the values of the
CMAKE_<LANG>_LINKER_WRAPPER_FLAG
and
CMAKE_<LANG>_LINKER_WRAPPER_FLAG_SEP
variables.
For example, "LINKER:-z,defs"
becomes -Xlinker -z -Xlinker defs
for
Clang
and -Wl,-z,defs
for GNU GCC
.
The LINKER:
prefix can be specified as part of a SHELL:
prefix
expression.
The LINKER:
prefix supports, as an alternative syntax, specification of
arguments using the SHELL:
prefix and space as separator. The previous
example then becomes "LINKER:SHELL:-z defs"
.
Note
Specifying the SHELL:
prefix anywhere other than at the beginning of the
LINKER:
prefix is not supported.