AddFileDependencies: Deprecate this unnecessary module

Document that one can call `set_property` directly instead.

1 files changed, 13 insertions, 1 deletions

diff --git a/Modules/AddFileDependencies.cmake b/Modules/AddFileDependencies.cmake
index c0388582b9..13b2600f9b 100644
--- a/Modules/AddFileDependencies.cmake
+++ b/Modules/AddFileDependencies.cmake
@@ -5,13 +5,25 @@
 AddFileDependencies
 -------------------
 
+.. deprecated:: 3.20
+
 Add dependencies to a source file.
 
 .. code-block:: cmake
 
-  add_file_dependencies(<source> <files>)
+  add_file_dependencies(<source> <files>...)
 
 Adds the given ``<files>`` to the dependencies of file ``<source>``.
+
+Do not use this command in new code.  It is just a wrapper around:
+
+.. code-block:: cmake
+
+  set_property(SOURCE <source> APPEND PROPERTY OBJECT_DEPENDS <files>...)
+
+Instead use the :command:`set_property` command to append to the
+:prop_sf:`OBJECT_DEPENDS` source file property directly.
+
 #]=======================================================================]
 
 function(add_file_dependencies _file)