updated for version 7.3.646 Problem: When reloading a buffer the undo file becomes unusable unless ":w" is executed. (Dmitri Frank) Solution: After reloading the buffer write the undo file. (Christian Brabandt)

--- a/src/version.c
+++ b/src/version.c
@@ -720,6 +720,8 @@ static char *(features[]) =
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    646,
+/**/
     645,
 /**/
     644,