patch 7.4.1521
Problem:    File permission test fails on MS-Windows.
Solution:   Expect a different permission.
diff --git a/src/version.c b/src/version.c
index 15baf5d..5d7a968 100644
--- a/src/version.c
+++ b/src/version.c
@@ -744,6 +744,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1521,
+/**/
     1520,
 /**/
     1519,