Update runtime files
diff --git a/runtime/doc/options.txt b/runtime/doc/options.txt
index 82b91a6..ab13d0c 100644
--- a/runtime/doc/options.txt
+++ b/runtime/doc/options.txt
@@ -1,4 +1,4 @@
-*options.txt*	For Vim version 8.2.  Last change: 2020 May 03
+*options.txt*	For Vim version 8.2.  Last change: 2020 May 31
 
 
 		  VIM REFERENCE MANUAL	  by Bram Moolenaar
@@ -5434,8 +5434,8 @@
 		    (without "unsigned" it would become "9-2021").
 		    Using CTRL-A on "2020" in "9-2020" results in "9-2021"
 		    (without "unsigned" it would become "9-2019").
-		    Using CTRL-X on "0" or "18446744073709551615" (2^64) has
-		    no effect, overflow is prevented.
+		    Using CTRL-X on "0" or CTRL-A on "18446744073709551615"
+		    (2^64 - 1) has no effect, overflow is prevented.
 	Numbers which simply begin with a digit in the range 1-9 are always
 	considered decimal.  This also happens for numbers that are not
 	recognized as octal or hex.