diff --git a/pkgs/development/libraries/hwloc/default.nix b/pkgs/development/libraries/hwloc/default.nix
index c0745cb9e687..ad39a4fde319 100644
--- a/pkgs/development/libraries/hwloc/default.nix
+++ b/pkgs/development/libraries/hwloc/default.nix
@@ -1,8 +1,9 @@
 { stdenv, fetchurl, pkgconfig, expat, ncurses, pciutils, numactl
-, cairo, libX11
-, x11Support ? (!stdenv.isCygwin)
+, x11Support ? false, libX11 ? null, cairo ? null
 }:
 
+assert x11Support -> libX11 != null && cairo != null;
+
 with stdenv.lib;
 
 stdenv.mkDerivation rec {
diff --git a/pkgs/development/libraries/libclc/default.nix b/pkgs/development/libraries/libclc/default.nix
index c5ba65e7b6d7..bd9130e3f507 100644
--- a/pkgs/development/libraries/libclc/default.nix
+++ b/pkgs/development/libraries/libclc/default.nix
@@ -1,16 +1,21 @@
-{ stdenv, fetchFromGitHub, python2, llvm_4, clang }:
+{ stdenv, fetchFromGitHub, python2, llvmPackages }:
+
+let
+  llvm = llvmPackages.llvm;
+  clang = llvmPackages.clang;
+in
 
 stdenv.mkDerivation {
-  name = "libclc-2017-02-25";
+  name = "libclc-2017-11-29";
 
   src = fetchFromGitHub {
     owner = "llvm-mirror";
     repo = "libclc";
-    rev = "17648cd846390e294feafef21c32c7106eac1e24";
-    sha256 = "1c20jyh3sdwd9r37zs4vvppmsx8vhf2xbx0cxsrc27bhx5245p0s";
+    rev = "d6384415ab854c68777dd77451aa2bc0d959da99";
+    sha256 = "10fqrlnqlknh58x7pfsbg9r07fblfg2mgq2m4fr1jbb836ncn3wh";
   };
 
-  buildInputs = [ python2 llvm_4 clang ];
+  buildInputs = [ python2 llvm clang ];
 
   postPatch = ''
     sed -i 's,llvm_clang =.*,llvm_clang = "${clang}/bin/clang",' configure.py
diff --git a/pkgs/development/libraries/ocl-icd/default.nix b/pkgs/development/libraries/ocl-icd/default.nix
index 6c3a77cfaf5e..75dda07494d9 100644
--- a/pkgs/development/libraries/ocl-icd/default.nix
+++ b/pkgs/development/libraries/ocl-icd/default.nix
@@ -9,14 +9,16 @@ stdenv.mkDerivation rec {
     sha256 = "0f14gpa13sdm0kzqv5yycp4pschbmi6n5fj7wl4ilspzsrqcgqr2";
   };
 
-  buildInputs = [ ruby opencl-headers ];
+  nativeBuildInputs = [ ruby ];
+
+  buildInputs = [ opencl-headers ];
 
   postPatch = ''
     sed -i 's,"/etc/OpenCL/vendors","${mesa_noglu.driverLink}/etc/OpenCL/vendors",g' ocl_icd_loader.c
   '';
 
   meta = with stdenv.lib; {
-    description = "OpenCL ICD Loader";
+    description = "OpenCL ICD Loader for ${opencl-headers.name}";
     homepage    = https://forge.imag.fr/projects/ocl-icd/;
     license     = licenses.bsd2;
     platforms = platforms.linux;
diff --git a/pkgs/development/libraries/opencl-headers/default.nix b/pkgs/development/libraries/opencl-headers/default.nix
index 717bb5ad0eed..9ce8bb618bf9 100644
--- a/pkgs/development/libraries/opencl-headers/default.nix
+++ b/pkgs/development/libraries/opencl-headers/default.nix
@@ -1,22 +1,24 @@
-{ stdenv, fetchFromGitHub }:
+{ stdenv, fetchFromGitHub
+, version # "12" for "1.2", "22" for "2.2" and so on
+}:
 
 stdenv.mkDerivation rec {
-  name = "opencl-headers-2.1-2016-11-29";
+  name = "opencl-headers-${version}-2017-07-18";
 
   src = fetchFromGitHub {
     owner = "KhronosGroup";
     repo = "OpenCL-Headers";
-    rev = "abb29588550c77f8340a6c3683531407013bf26b";
-    sha256 = "0zjznq65i4b2h4k36qfbbzq1acf2jdd9vygjv5az1yk7qgsp4jj7";
+    rev = "f039db6764d52388658ef15c30b2237bbda49803";
+    sha256 = "0z04i330zr8czak2624q71aajdcq7ly8mb5bgala5m235qjpsrh7";
   };
 
   installPhase = ''
     mkdir -p $out/include/CL
-    cp * $out/include/CL
+    cp opencl${version}/CL/* $out/include/CL
   '';
 
   meta = with stdenv.lib; {
-    description = "Khronos OpenCL headers";
+    description = "Khronos OpenCL headers version ${version}";
     homepage = https://www.khronos.org/registry/cl/;
     license = licenses.mit;
     platforms = platforms.unix;
diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index 716ca74e015c..4546287862e4 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -9343,7 +9343,9 @@ with pkgs;
 
   libchop = callPackage ../development/libraries/libchop { };
 
-  libclc = callPackage ../development/libraries/libclc { };
+  libclc = callPackage ../development/libraries/libclc {
+    llvmPackages = llvmPackages_5;
+  };
 
   libcli = callPackage ../development/libraries/libcli { };
 
@@ -10419,7 +10421,10 @@ with pkgs;
 
   nvidia-video-sdk = callPackage ../development/libraries/nvidia-video-sdk { };
 
-  ocl-icd = callPackage ../development/libraries/ocl-icd { };
+  ocl-icd-oclhGen = oclh: callPackage ../development/libraries/ocl-icd { opencl-headers = oclh; };
+  ocl-icd-oclh_1_2 = ocl-icd-oclhGen opencl-headers_1_2;
+  ocl-icd-oclh_2_2 = ocl-icd-oclhGen opencl-headers_2_2;
+  ocl-icd = ocl-icd-oclh_2_2;
 
   ode = callPackage ../development/libraries/ode { };
 
@@ -10446,7 +10451,10 @@ with pkgs;
 
   opencascade_oce = opencascade;
 
-  opencl-headers = callPackage ../development/libraries/opencl-headers { };
+  opencl-headersGen = v: callPackage ../development/libraries/opencl-headers { version = v; };
+  opencl-headers_1_2 = opencl-headersGen "12";
+  opencl-headers_2_2 = opencl-headersGen "22";
+  opencl-headers = opencl-headers_2_2;
 
   opencl-clhpp = callPackage ../development/libraries/opencl-clhpp { };