patch 7.4.2128
Problem:    Memory leak when saving for undo fails.
Solution:   Free allocated memory. (Hirohito Higashi)
diff --git a/src/ex_cmds.c b/src/ex_cmds.c
index 860d3dc..e40e435 100644
--- a/src/ex_cmds.c
+++ b/src/ex_cmds.c
@@ -4091,7 +4091,10 @@
 	    u_sync(FALSE);
 	    if (u_savecommon(0, curbuf->b_ml.ml_line_count + 1, 0, TRUE)
 								     == FAIL)
+	    {
+		vim_free(new_name);
 		goto theend;
+	    }
 	    u_unchanged(curbuf);
 	    buf_freeall(curbuf, BFA_KEEP_UNDO);