# add_link_options

Adds options to the link of shared library, module and executable targets.

    add_link_options(<option> ...)

Adds options to the link step for targets in the current directory and below that are added after this command is invoked. See documentation of the `directory` and `target` `LINK_OPTIONS` properties.

This command can be used to add any options, but alternative commands exist to add libraries (`target_link_libraries()` or `link_libraries()`).

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.

To pass options to the linker tool, each compiler driver has is own syntax. The `LINKER:` prefix can be used to specify, in a portable way, options to pass to the linker tool. The `LINKER:` prefix is replaced by the required driver option and the rest of the option string defines linker arguments using `,` as separator. These arguments will be formatted according to 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 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 it 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`.