diff --git a/src/ops.c b/src/ops.c
index f08e576..9b669b3 100644
--- a/src/ops.c
+++ b/src/ops.c
@@ -3351,6 +3351,12 @@
 	    return;
     }
 
+#ifdef FEAT_AUTOCMD
+    /* Autocommands may be executed when saving lines for undo, which may make
+     * y_array invalid.  Start undo now to avoid that. */
+    u_save(curwin->w_cursor.lnum, curwin->w_cursor.lnum + 1);
+#endif
+
     if (insert_string != NULL)
     {
 	y_type = MCHAR;
diff --git a/src/version.c b/src/version.c
index aec15bd..562bb04 100644
--- a/src/version.c
+++ b/src/version.c
@@ -726,6 +726,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    757,
+/**/
     756,
 /**/
     755,