patch 7.4.1640
Problem:    Crash when an autocommand changes a quickfix list. (Dominique)
Solution:   Check wether an entry is still valid. (Yegappan Lakshmanan,
            Hirohito Higashi)
diff --git a/src/version.c b/src/version.c
index 6fffeeb..c9c550a 100644
--- a/src/version.c
+++ b/src/version.c
@@ -749,6 +749,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1640,
+/**/
     1639,
 /**/
     1638,