commit https://github.com/vim/vim/commit/b681be175b6991cdc2b8ddd49b0e97e3fe2b201e Author: Bram Moolenaar <Bram@vim.org> Date: Thu Mar 31 23:02:16 2016 +0200 patch 7.4.1691 Problem: When switching to a new buffer and an autocommand applies syntax highlighting an ml_get error may occur. Solution: Check "syn_buf" against the buffer in the window. (Alexander von Buddenbrock, closes #676)

--- a/src/version.c
+++ b/src/version.c
@@ -749,6 +749,8 @@ static char *(features[]) =
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1691,
+/**/
     1690,
 /**/
     1689,