From 5c06f350cee4d52554194a90e1d070f4f53979d3 Mon Sep 17 00:00:00 2001
From: Shougo Matsushita <Shougo.Matsu@gmail.com>
Date: Tue, 22 Nov 2016 07:31:40 +0900
Subject: [PATCH] vim-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 vim/vim#676)

https://github.com/vim/vim/commit/b681be175b6991cdc2b8ddd49b0e97e3fe2b201e
---
 src/nvim/syntax.c  | 4 +++-
 src/nvim/version.c | 2 +-
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/src/nvim/syntax.c b/src/nvim/syntax.c
index e57965ac2c..cd37bde3cb 100644
--- a/src/nvim/syntax.c
+++ b/src/nvim/syntax.c
@@ -392,7 +392,9 @@ void syntax_start(win_T *wp, linenr_T lnum)
    * Also do this when a change was made, the current state may be invalid
    * then.
    */
-  if (syn_block != wp->w_s || changedtick != syn_buf->b_changedtick) {
+  if (syn_block != wp->w_s
+      || syn_buf != wp->w_buffer
+      || changedtick != syn_buf->b_changedtick) {
     invalidate_current_state();
     syn_buf = wp->w_buffer;
     syn_block = wp->w_s;
diff --git a/src/nvim/version.c b/src/nvim/version.c
index 8f3619f1e8..8684d840d9 100644
--- a/src/nvim/version.c
+++ b/src/nvim/version.c
@@ -753,7 +753,7 @@ static int included_patches[] = {
   // 1694 NA
   // 1693 NA
   // 1692,
-  // 1691,
+  1691,
   // 1690 NA
   // 1689 NA
   // 1688 NA