Add tests for PoCL with and without using icd

test/compilers/pocl.nix

@@ -9,18 +9,18 @@ runCommand "clinfo-pocl"
   {
     nativeBuildInputs = [
       clinfo
+      pocl
       writableTmpDirAsHomeHook
     ];
 
     requiredSystemFeatures = [ "sys-devices" ];
 
-    env = {
-      POCL_DEBUG = "error,warn";
-      OCL_ICD_VENDORS = "${pocl}/etc/OpenCL/vendors";
-    };
+    env.POCL_DEBUG = "error,warn";
   }
   ''
-    set -x
-    clinfo | tee $out
-    set +x
+    echo $OCL_ICD_VENDORS
+    clinfo >$out
+
+    # check that we have PoCL:
+    grep "Portable Computing Language" $out
   ''