diff --git a/runtime/doc/builtin.txt b/runtime/doc/builtin.txt
index 4fb12ff..f6a791d 100644
--- a/runtime/doc/builtin.txt
+++ b/runtime/doc/builtin.txt
@@ -2270,6 +2270,9 @@
 		is not defined, an empty string is used.  Using "%:p" in a
 		buffer with no name, results in the current directory, with a
 		'/' added.
+		When 'verbose' is set then expanding '%', '#' and <> items
+		will result in an error message if the argument cannot be
+		expanded.
 
 		When {string} does not start with '%', '#' or '<', it is
 		expanded like a file name is expanded on the command line.