From 953d34fd1fd004459704d4625aff54a9dcf9141b Mon Sep 17 00:00:00 2001
From: Brad King <brad.king@kitware.com>
Date: Tue, 16 Dec 2014 10:38:43 -0500
Subject: [PATCH] Help: Document MAIN_DEPENDENCY limitation in
 add_custom_command

Specify explicitly that at most one custom command may use a given
source file as its main dependency.
---
 Help/command/add_custom_command.rst | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/Help/command/add_custom_command.rst b/Help/command/add_custom_command.rst
index 9fbad4bf6..1307a58c5 100644
--- a/Help/command/add_custom_command.rst
+++ b/Help/command/add_custom_command.rst
@@ -130,7 +130,8 @@ The options are:
   Specify the primary input source file to the command.  This is
   treated just like any value given to the ``DEPENDS`` option
   but also suggests to Visual Studio generators where to hang
-  the custom command.
+  the custom command.  At most one custom command may specify a
+  given source file as its main dependency.
 
 ``OUTPUT``
   Specify the output files the command is expected to produce.