diff --git a/.hgtags b/.hgtags
index 1785881558..2278ce5950 100644
--- a/.hgtags
+++ b/.hgtags
@@ -6,3 +6,4 @@ a358b629d083fbbe619614fcf3f26efaa21ff057 3.0.0
 f72cb08228d56df2be724b462e5d9497dc700285 3.4.0
 8f644f057381856d5ab1834f34a981ff1b65fba3 3.6.0
 2918a530bb167f85c238e2dafe30ee6cf942ea70 3.8.0
+571f01b197f02ef5842c30e25e66515c9d1fa0c4 4.0.0