diff --git a/pkgs/build-support/buildenv/default.nix b/pkgs/build-support/buildenv/default.nix
index dc05ec1678cb..47e2c1b904c3 100644
--- a/pkgs/build-support/buildenv/default.nix
+++ b/pkgs/build-support/buildenv/default.nix
@@ -2,7 +2,7 @@
 # a fork of the buildEnv in the Nix distribution.  Most changes should
 # eventually be merged back into the Nix distribution.
 
-{ perl, runCommand, lib }:
+{ buildPackages, runCommand, lib }:
 
 { name
 
@@ -66,6 +66,6 @@ runCommand name
     passAsFile = if builtins.stringLength pkgs >= 128*1024 then [ "pkgs" ] else null;
   }
   ''
-    ${perl}/bin/perl -w ${./builder.pl}
+    ${buildPackages.perl}/bin/perl -w ${./builder.pl}
     eval "$postBuild"
   ''
diff --git a/pkgs/os-specific/linux/kmod/default.nix b/pkgs/os-specific/linux/kmod/default.nix
index 138130fa82e4..5d0dca7b6bec 100644
--- a/pkgs/os-specific/linux/kmod/default.nix
+++ b/pkgs/os-specific/linux/kmod/default.nix
@@ -1,4 +1,4 @@
-{ stdenv, lib, fetchurl, autoreconfHook, xz, zlib, pkgconfig, libxslt }:
+{ stdenv, buildPackages, lib, fetchurl, autoreconfHook, pkgconfig, libxslt, xz }:
 
 let
   systems = [ "/run/current-system/kernel-modules" "/run/booted-system/kernel-modules" "" ];
@@ -14,13 +14,14 @@ in stdenv.mkDerivation rec {
   };
 
   nativeBuildInputs = [ autoreconfHook pkgconfig libxslt ];
-  buildInputs = [ xz /* zlib */ ];
+  buildInputs = [ xz ];
+  # HACK until BUG issue #21191 is addressed
+  crossAttrs.preUnpack = ''PATH="${buildPackages.xz}/bin''${PATH:+:}$PATH"'';
 
   configureFlags = [
     "--sysconfdir=/etc"
     "--with-xz"
     "--with-modulesdirs=${modulesDirs}"
-    # "--with-zlib"
   ];
 
   patches = [ ./module-dir.patch ];
diff --git a/pkgs/tools/misc/coreutils/default.nix b/pkgs/tools/misc/coreutils/default.nix
index 455937f3a67c..d87976cbc5e8 100644
--- a/pkgs/tools/misc/coreutils/default.nix
+++ b/pkgs/tools/misc/coreutils/default.nix
@@ -53,7 +53,7 @@ stdenv.mkDerivation rec {
       ++ optional aclSupport acl.crossDrv
       ++ optional attrSupport attr.crossDrv
       ++ optionals selinuxSupport [ libselinux.crossDrv libsepol.crossDrv ]
-      ++ optional (stdenv.ccCross.libc ? libiconv)
+      ++ optional (stdenv ? ccCross.libc.libiconv)
         stdenv.ccCross.libc.libiconv.crossDrv;
 
     # Prevents attempts of running 'help2man' on cross-built binaries.
diff --git a/pkgs/tools/networking/netcat-openbsd/default.nix b/pkgs/tools/networking/netcat-openbsd/default.nix
index 9933b512006f..ef539cbb51fd 100644
--- a/pkgs/tools/networking/netcat-openbsd/default.nix
+++ b/pkgs/tools/networking/netcat-openbsd/default.nix
@@ -15,7 +15,9 @@ stdenv.mkDerivation rec {
     })
   ];
 
-  buildInputs = [ pkgconfig libbsd ];
+  nativeBuildInputs = [ pkgconfig ];
+  buildInputs = [ libbsd ];
+
   sourceRoot = name;
   patches = [ "../debian/patches/*.patch" ];