Update runtime files
diff --git a/runtime/doc/options.txt b/runtime/doc/options.txt
index dc6e16b..a514b6f 100644
--- a/runtime/doc/options.txt
+++ b/runtime/doc/options.txt
@@ -1,4 +1,4 @@
-*options.txt*	For Vim version 9.0.  Last change: 2022 Dec 31
+*options.txt*	For Vim version 9.0.  Last change: 2023 Jan 02
 
 
 		  VIM REFERENCE MANUAL	  by Bram Moolenaar
@@ -7686,6 +7686,8 @@
 
 	When there is error while evaluating the option then it will be made
 	empty to avoid further errors.  Otherwise screen updating would loop.
+	When the result contains unprintable characters the result is
+	unpredictable.
 
 	Note that the only effect of 'ruler' when this option is set (and
 	'laststatus' is 2) is controlling the output of |CTRL-G|.