LINK_OPTIONS: Add new family of properties

This family enable to manage link flags

Three new properties:
* directory property: LINK_OPTIONS
* target properties: LINK_OPTIONS and INTERFACE_LINK_OPTIONS

Two new commands
* add_link_options(): to populate directory property
* target_link_options(): to populate target properties

Fixes: #16543

Help/command/OPTIONS_SHELL.txt

@@ -1,4 +1,4 @@
-The final set of compile options used for a target is constructed by
+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

Help/command/add_compile_options.rst

@@ -22,4 +22,4 @@ the syntax ``$<...>``.  See the :manual:`cmake-generator-expressions(7)`
 manual for available expressions.  See the :manual:`cmake-buildsystem(7)`
 manual for more on defining buildsystem properties.
 
-.. include:: COMPILE_OPTIONS_SHELL.txt
+.. include:: OPTIONS_SHELL.txt

Help/command/add_link_options.rst

@@ -0,0 +1,24 @@
+add_link_options
+----------------
+
+Adds options to the link of targets.
+
+::
+
+  add_link_options(<option> ...)
+
+Adds options to the linker command line for targets in the current
+directory and below that are added after this command is invoked.
+See documentation of the :prop_dir:`directory <LINK_OPTIONS>` and
+:prop_tgt:`target <LINK_OPTIONS>` ``LINK_OPTIONS`` properties.
+
+This command can be used to add any options, but alternative command
+exist to add libraries (:command:`target_link_libraries` or
+:command:`link_libraries`).
+
+Arguments to ``add_link_options`` may use "generator expressions" with
+the syntax ``$<...>``.  See the :manual:`cmake-generator-expressions(7)`
+manual for available expressions.  See the :manual:`cmake-buildsystem(7)`
+manual for more on defining buildsystem properties.
+
+.. include:: OPTIONS_SHELL.txt

Help/command/target_compile_options.rst

@@ -39,4 +39,4 @@ with the syntax ``$<...>``. See the :manual:`cmake-generator-expressions(7)`
 manual for available expressions.  See the :manual:`cmake-buildsystem(7)`
 manual for more on defining buildsystem properties.
 
-.. include:: COMPILE_OPTIONS_SHELL.txt
+.. include:: OPTIONS_SHELL.txt

Help/command/target_link_libraries.rst

@@ -70,7 +70,8 @@ Each ``<item>`` may be:
 
   Link flags specified here are inserted into the link command in the same
   place as the link libraries. This might not be correct, depending on
-  the linker. Use the :prop_tgt:`LINK_FLAGS` target property to add link
+  the linker. Use the :prop_tgt:`LINK_OPTIONS` target property or
+  :command:`target_link_options` command to add link
   flags explicitly. The flags will then be placed at the toolchain-defined
   flag position in the link command.
 

Help/command/target_link_options.rst

@@ -0,0 +1,40 @@
+target_link_options
+-------------------
+
+Add link options to a target.
+
+::
+
+  target_link_options(<target> [BEFORE]
+    <INTERFACE|PUBLIC|PRIVATE> [items1...]
+    [<INTERFACE|PUBLIC|PRIVATE> [items2...] ...])
+
+Specify link options to use when linking a given target.  The
+named ``<target>`` must have been created by a command such as
+:command:`add_executable` or :command:`add_library` and must not be an
+:ref:`ALIAS target <Alias Targets>`.
+
+If ``BEFORE`` is specified, the content will be prepended to the property
+instead of being appended.
+
+This command can be used to add any options, but
+alternative commands exist to add libraries
+(:command:`target_link_libraries` and :command:`link_libraries`).
+See documentation of the :prop_dir:`directory <LINK_OPTIONS>` and
+:prop_tgt:`target <LINK_OPTIONS>` ``LINK_OPTIONS`` properties.
+
+The ``INTERFACE``, ``PUBLIC`` and ``PRIVATE`` keywords are required to
+specify the scope of the following arguments.  ``PRIVATE`` and ``PUBLIC``
+items will populate the :prop_tgt:`LINK_OPTIONS` property of
+``<target>``.  ``PUBLIC`` and ``INTERFACE`` items will populate the
+:prop_tgt:`INTERFACE_LINK_OPTIONS` property of ``<target>``.
+(:ref:`IMPORTED targets <Imported Targets>` only support ``INTERFACE`` items.)
+The following arguments specify compile 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 :manual:`cmake-generator-expressions(7)`
+manual for available expressions.  See the :manual:`cmake-buildsystem(7)`
+manual for more on defining buildsystem properties.
+
+.. include:: OPTIONS_SHELL.txt