diff --git a/pkgs/development/libraries/gdbm/default.nix b/pkgs/development/libraries/gdbm/default.nix
index ecab75fb0ea..bbebcca6e2f 100644
--- a/pkgs/development/libraries/gdbm/default.nix
+++ b/pkgs/development/libraries/gdbm/default.nix
@@ -2,6 +2,8 @@
 
 stdenv.mkDerivation rec {
   name = "gdbm-1.17";
+  # FIXME: remove on update to > 1.17
+  NIX_CFLAGS_COMPILE = if stdenv.cc.isClang then "-Wno-error=return-type" else null;
 
   src = fetchurl {
     url = "mirror://gnu/gdbm/${name}.tar.gz";
diff --git a/pkgs/development/libraries/libtiff/default.nix b/pkgs/development/libraries/libtiff/default.nix
index d37e93e6f82..bf0393fd89a 100644
--- a/pkgs/development/libraries/libtiff/default.nix
+++ b/pkgs/development/libraries/libtiff/default.nix
@@ -13,6 +13,8 @@ stdenv.mkDerivation rec {
 
   prePatch = let
       debian = fetchurl {
+        # When the URL disappears, it typically means that Debian has new patches
+        # (probably security) and updating to new tarball will apply them as well.
         url = http://http.debian.net/debian/pool/main/t/tiff/tiff_4.0.9-6.debian.tar.xz;
         sha256 = "10yk5npchxscgsnd7ihd3bbbw2fxkl7ni0plm43c9q4nwp6ms52f";
       };
diff --git a/pkgs/os-specific/linux/util-linux/default.nix b/pkgs/os-specific/linux/util-linux/default.nix
index 1a7232afedb..55673ccf013 100644
--- a/pkgs/os-specific/linux/util-linux/default.nix
+++ b/pkgs/os-specific/linux/util-linux/default.nix
@@ -39,7 +39,7 @@ in stdenv.mkDerivation rec {
     "--disable-use-tty-group"
     "--enable-fs-paths-default=/run/wrappers/bin:/var/run/current-system/sw/bin:/sbin"
     "--disable-makeinstall-setuid" "--disable-makeinstall-chown"
-    (lib.withFeature (ncurses != null) "ncurses")
+    (lib.withFeature (ncurses != null) "ncursesw")
     (lib.withFeature (systemd != null) "systemd")
     (lib.withFeatureAs (systemd != null)
        "systemdsystemunitdir" "$bin/lib/systemd/system/")