diff --git a/Cargo.toml b/Cargo.toml
index cefdd46..b0ffb5f 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "libz-sys"
-version = "1.1.20"
+version = "1.1.21"
 authors = [
     "Alex Crichton <alex@alexcrichton.com>",
     "Josh Triplett <josh@joshtriplett.org>",
diff --git a/src/zlib-ng b/src/zlib-ng
index c939498..cbb6ec1 160000
--- a/src/zlib-ng
+++ b/src/zlib-ng
@@ -1 +1 @@
-Subproject commit c939498c7f2a1d645833a98251365e2c814fd736
+Subproject commit cbb6ec1d74e8061efdf7251f8c2dae778bed14fd