diff --git a/pkgs/development/libraries/fontconfig/default.nix b/pkgs/development/libraries/fontconfig/default.nix
index 1f1074096839..aa3ab19bf334 100644
--- a/pkgs/development/libraries/fontconfig/default.nix
+++ b/pkgs/development/libraries/fontconfig/default.nix
@@ -13,6 +13,14 @@ stdenv.mkDerivation rec {
 
   configureFlags = "--with-confdir=/etc/fonts --with-cache-dir=/var/cache/fontconfig --disable-docs --with-default-fonts=";
 
+  crossArch = stdenv.cross.arch;
+
+  preConfigure = ''
+    if test -n "$crossConfig"; then
+      configureFlags="$configureFlags --with-arch=$crossArch";
+    fi
+  '';
+
   # Don't try to write to /etc/fonts or /var/cache/fontconfig at install time.
   installFlags = "CONFDIR=$(out)/etc/fonts RUN_FC_CACHE_TEST=false fc_cachedir=$(TMPDIR)/dummy";
 
diff --git a/pkgs/development/libraries/libdrm/default.nix b/pkgs/development/libraries/libdrm/default.nix
index 53c66ae7c151..ea10c3ee8d2c 100644
--- a/pkgs/development/libraries/libdrm/default.nix
+++ b/pkgs/development/libraries/libdrm/default.nix
@@ -10,6 +10,13 @@ stdenv.mkDerivation rec {
 
   buildInputs = [ pkgconfig libpthreadstubs ];
 
+  preConfigure = ''
+    # General case: non intel.
+    if test -n "$crossConfig"; then
+      configureFlags="$configureFlags --disable-intel";
+    fi
+  '';
+
   meta = {
     homepage = http://dri.freedesktop.org/libdrm/;
     description = "Library for accessing the kernel's Direct Rendering Manager";
diff --git a/pkgs/development/libraries/zlib/default.nix b/pkgs/development/libraries/zlib/default.nix
index f59182c2ba58..b4ae9e63ea08 100644
--- a/pkgs/development/libraries/zlib/default.nix
+++ b/pkgs/development/libraries/zlib/default.nix
@@ -8,6 +8,13 @@ stdenv.mkDerivation {
   };
   configureFlags = if static then "" else "--shared";
 
+  preConfigure = ''
+    if test -n "$crossConfig"; then
+      export CC=$crossConfig-gcc
+      configureFlags=${if static then "" else "--shared"}
+    fi
+  '';
+
   # zlib doesn't like the automatic --disable-shared from the Cygwin stdenv.
   cygwinConfigureEnableShared = true;
 }
diff --git a/pkgs/servers/x11/xorg/overrides.nix b/pkgs/servers/x11/xorg/overrides.nix
index 23937c8978e2..8114567c1b6f 100644
--- a/pkgs/servers/x11/xorg/overrides.nix
+++ b/pkgs/servers/x11/xorg/overrides.nix
@@ -22,7 +22,17 @@
   };
 
   libxcb = attrs : attrs // {
-    buildInputs = attrs.buildInputs ++ [ xorg.xproto ];
+    # I only remove python from the original, and add xproto. I don't know how
+    # to achieve that referring to attrs.buildInputs.
+    buildInputs = [args.pkgconfig args.libxslt xorg.libpthreadstubs /*xorg.python*/
+        xorg.libXau xorg.xcbproto xorg.libXdmcp ] ++ [ xorg.xproto ];
+    buildNativeInputs = [ args.python ];
+  };
+
+  xcbproto = attrs : attrs // {
+    # I only remove python from the original.
+    buildInputs = [args.pkgconfig  /*xorg.python*/ ];
+    buildNativeInputs = [ args.python ];
   };
 
   libXext = attrs: attrs // {
diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index 2fb6471ed079..899765315840 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -2874,11 +2874,16 @@ let
    * pkgconfig is optionally taken from the stdenv to allow bootstrapping
    * of glib and pkgconfig itself on MinGW.
    */
-  pkgconfig = useFromStdenv "pkgconfig"
+  pkgconfigReal = useFromStdenv "pkgconfig"
     (import ../development/tools/misc/pkgconfig {
       inherit fetchurl stdenv;
     });
 
+  /* Make pkgconfig always return a buildDrv, never a proper hostDrv,
+     because most usage of pkgconfig as buildInput (inheritance of
+     pre-cross nixpkgs) means using it using as buildNativeInput */
+  pkgconfig = pkgconfigReal // { hostDrv = pkgconfigReal.buildDrv; };
+
   radare = import ../development/tools/analysis/radare {
     inherit stdenv fetchurl pkgconfig libusb readline gtkdialog python
       ruby libewf perl;