diff --git a/src/undo.c b/src/undo.c
index b2c4e9a..1cd8912 100644
--- a/src/undo.c
+++ b/src/undo.c
@@ -123,6 +123,7 @@
 static void unserialize_visualinfo(bufinfo_T *bi, visualinfo_T *info);
 #endif
 static void u_saveline(linenr_T lnum);
+static void u_blockfree(buf_T *buf);
 
 #define U_ALLOC_LINE(size) lalloc(size, FALSE)
 
@@ -3472,7 +3473,7 @@
 /*
  * invalidate the undo buffer; called when storage has already been released
  */
-    void
+    static void
 u_clearall(buf_T *buf)
 {
     buf->b_u_newhead = buf->b_u_oldhead = buf->b_u_curhead = NULL;
@@ -3484,6 +3485,30 @@
 }
 
 /*
+ * Free all allocated memory blocks for the buffer 'buf'.
+ */
+    static void
+u_blockfree(buf_T *buf)
+{
+    while (buf->b_u_oldhead != NULL)
+	u_freeheader(buf, buf->b_u_oldhead, NULL);
+    vim_free(buf->b_u_line_ptr.ul_line);
+}
+
+/*
+ * Free all allocated memory blocks for the buffer 'buf'.
+ * and invalidate the undo buffer
+ */
+    void
+u_clearallandblockfree(buf_T *buf)
+{
+    u_blockfree(buf);
+    u_clearall(buf);
+}
+
+
+
+/*
  * Save the line "lnum" for the "U" command.
  */
     static void
@@ -3563,17 +3588,6 @@
 }
 
 /*
- * Free all allocated memory blocks for the buffer 'buf'.
- */
-    void
-u_blockfree(buf_T *buf)
-{
-    while (buf->b_u_oldhead != NULL)
-	u_freeheader(buf, buf->b_u_oldhead, NULL);
-    vim_free(buf->b_u_line_ptr.ul_line);
-}
-
-/*
  * Check if the 'modified' flag is set, or 'ff' has changed (only need to
  * check the first character, because it can only be "dos", "unix" or "mac").
  * "nofile" and "scratch" type buffers are considered to always be unchanged.