add_link_options¶
New in version 3.13.
Add options to the link step for executable, shared library or module library targets in the current directory and below that are added after this command is invoked.
add_link_options(<option> ...)
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.
Arguments to add_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.
Host And Device Specific Link Options¶
New in version 3.18: When a device link step is involved, which is controlled by
CUDA_SEPARABLE_COMPILATION
and
CUDA_RESOLVE_DEVICE_SYMBOLS
properties and policy CMP0105
,
the raw options will be delivered to the host and device link steps (wrapped in
-Xcompiler
or equivalent for device link). Options wrapped with
$<DEVICE_LINK:...>
generator expression
will be used
only for the device link step. Options wrapped with $<HOST_LINK:...>
generator expression
will be used
only for the host link step.
Option De-duplication¶
The final set of 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.
New in version 3.12: While beneficial for individual options, the de-duplication step can break
up option groups. For example, -option A -option B
becomes
-option 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:-option A" "SHELL:-option B"
becomes -option A -option B
.
Handling Compiler Driver Differences¶
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.