diff --git a/com.oracle.truffle.r.nodes.test/src/com/oracle/truffle/r/nodes/casts/CastUtils.java b/com.oracle.truffle.r.nodes.test/src/com/oracle/truffle/r/nodes/casts/CastUtils.java
index f29e0c1400098cd021e1ab6cdbc77434a90cdfb7..8c0f67061b15afcc38a8a3639cd1a4fcb9d1ae5c 100644
--- a/com.oracle.truffle.r.nodes.test/src/com/oracle/truffle/r/nodes/casts/CastUtils.java
+++ b/com.oracle.truffle.r.nodes.test/src/com/oracle/truffle/r/nodes/casts/CastUtils.java
@@ -565,19 +565,19 @@ public class CastUtils {
     public static Class<?>[] rTypeToClasses(RType type) {
         switch (type) {
             case Integer:
-                return new Class[]{Integer.class, RAbstractIntVector.class};
+                return new Class<?>[]{Integer.class, RAbstractIntVector.class};
             case Double:
-                return new Class[]{Double.class, RAbstractDoubleVector.class};
+                return new Class<?>[]{Double.class, RAbstractDoubleVector.class};
             case Logical:
-                return new Class[]{Byte.class, RAbstractLogicalVector.class};
+                return new Class<?>[]{Byte.class, RAbstractLogicalVector.class};
             case Character:
-                return new Class[]{String.class, RAbstractStringVector.class};
+                return new Class<?>[]{String.class, RAbstractStringVector.class};
             case Complex:
-                return new Class[]{RAbstractComplexVector.class};
+                return new Class<?>[]{RAbstractComplexVector.class};
             case Raw:
-                return new Class[]{RAbstractRawVector.class};
+                return new Class<?>[]{RAbstractRawVector.class};
             case Any:
-                return new Class[]{Object.class};
+                return new Class<?>[]{Object.class};
         }
         return null;
     }
@@ -771,7 +771,7 @@ public class CastUtils {
     }
 
     public static Set<?> sampleValuesForClass(Class<?> cls) {
-        return sampleValuesForClasses(new Class[]{cls});
+        return sampleValuesForClasses(new Class<?>[]{cls});
     }
 
     public static Set<?> sampleValuesForType(Type t) {
diff --git a/com.oracle.truffle.r.nodes.test/src/com/oracle/truffle/r/nodes/casts/SamplesCollector.java b/com.oracle.truffle.r.nodes.test/src/com/oracle/truffle/r/nodes/casts/SamplesCollector.java
index 7048b7a331249a9ef36c80779eb89a56a12bd26a..76938d51b4e3cd93ed6f0d8d835fa3d9f0f8b0c3 100644
--- a/com.oracle.truffle.r.nodes.test/src/com/oracle/truffle/r/nodes/casts/SamplesCollector.java
+++ b/com.oracle.truffle.r.nodes.test/src/com/oracle/truffle/r/nodes/casts/SamplesCollector.java
@@ -223,7 +223,7 @@ public class SamplesCollector extends ExecutionPathVisitor<Consumer<Object>>
 
     @Override
     public Consumer<Object> visit(TypeFilter<?, ?> filter, Consumer<Object> previous) {
-        Class<?>[] filterTypes = new Class[]{filter.getType1(), filter.getType2()};
+        Class<?>[] filterTypes = new Class<?>[]{filter.getType1(), filter.getType2()};
         Set<?> samples = CastUtils.sampleValuesForClasses(filterTypes);
         for (Object s : samples) {
             previous.accept(s);
diff --git a/com.oracle.truffle.r.nodes.test/src/com/oracle/truffle/r/nodes/test/ChimneySweeping.java b/com.oracle.truffle.r.nodes.test/src/com/oracle/truffle/r/nodes/test/ChimneySweeping.java
index 10f273d4c701eebe429a74fcd142323a33abc6e5..c7ebd9a4b45ef038c3fed69010417971c27dacab 100644
--- a/com.oracle.truffle.r.nodes.test/src/com/oracle/truffle/r/nodes/test/ChimneySweeping.java
+++ b/com.oracle.truffle.r.nodes.test/src/com/oracle/truffle/r/nodes/test/ChimneySweeping.java
@@ -265,7 +265,6 @@ class ChimneySweeping extends SingleBuiltinDiagnostics {
         return true;
     }
 
-    @SuppressWarnings({"rawtypes", "unchecked"})
     private List<Samples<?>> createSamples() {
         DefaultArgsExtractor defArgExt = new DefaultArgsExtractor(diagSuite.fastRSession, msg -> print(1, msg));
         Map<String, Samples<?>> defaultArgs = defArgExt.extractDefaultArgs(builtinName);
@@ -274,7 +273,7 @@ class ChimneySweeping extends SingleBuiltinDiagnostics {
 
         List<Samples<?>> as = new ArrayList<>();
         for (int i = 0; i < argLength; i++) {
-            Samples samples;
+            Samples<?> samples;
 
             if (diagSuite.diagConfig.missingAndNullSamplesOnly) {
                 samples = Samples.anything(RNull.instance).or(Samples.anything(RMissing.instance));
@@ -296,7 +295,7 @@ class ChimneySweeping extends SingleBuiltinDiagnostics {
                     throw new RuntimeException("Error in sample generation from argument " + i, e);
                 }
 
-                Samples defArgSamples = defaultArgs.get(parameterNames[i]);
+                Samples<?> defArgSamples = defaultArgs.get(parameterNames[i]);
                 samples = defArgSamples == null ? samples : samples.and(defArgSamples);
             }
 
@@ -308,9 +307,8 @@ class ChimneySweeping extends SingleBuiltinDiagnostics {
     }
 
     /**
-     * Checks whether the argument samples are correct by passing them to the argument's pipeline.
-     * The positive samples should pass without any error, while the negative ones should cause an
-     * error.
+     * Checks whether the argument samples are correct by passing them to the argument's pipeline. The
+     * positive samples should pass without any error, while the negative ones should cause an error.
      *
      * @param i
      */
diff --git a/com.oracle.truffle.r.nodes.test/src/com/oracle/truffle/r/nodes/test/ExtBuiltinsList.java b/com.oracle.truffle.r.nodes.test/src/com/oracle/truffle/r/nodes/test/ExtBuiltinsList.java
index 22db6fbbd0270e95d101efb26d08047f158e2ba1..9b6a77256bb1aa1a8f8a46a25cb73c9a4e4028d4 100644
--- a/com.oracle.truffle.r.nodes.test/src/com/oracle/truffle/r/nodes/test/ExtBuiltinsList.java
+++ b/com.oracle.truffle.r.nodes.test/src/com/oracle/truffle/r/nodes/test/ExtBuiltinsList.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2017, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2017, 2018, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -32,7 +32,7 @@ import com.oracle.truffle.r.nodes.builtin.RExternalBuiltinNode;
  */
 public class ExtBuiltinsList {
 
-    @SuppressWarnings("rawtypes") private static final Class[] builtins = {
+    private static final List<Class<? extends RExternalBuiltinNode>> builtins = Arrays.asList(
                     com.oracle.truffle.r.nodes.builtin.RInternalCodeBuiltinNode.class,
                     com.oracle.truffle.r.nodes.objects.NewObjectNodeGen.class,
                     com.oracle.truffle.r.nodes.objects.GetPrimNameNodeGen.class,
@@ -90,11 +90,9 @@ public class ExtBuiltinsList {
                     com.oracle.truffle.r.library.methods.MethodsListDispatchFactory.R_getGenericNodeGen.class,
                     com.oracle.truffle.r.library.methods.MethodsListDispatchFactory.R_nextMethodCallNodeGen.class,
                     com.oracle.truffle.r.library.methods.MethodsListDispatchFactory.R_externalPtrPrototypeObjectNodeGen.class,
-                    com.oracle.truffle.r.library.stats.deriv.DerivNodeGen.class,
-    };
+                    com.oracle.truffle.r.library.stats.deriv.DerivNodeGen.class);
 
-    @SuppressWarnings("unchecked")
     public static List<Class<? extends RExternalBuiltinNode>> getBuiltins() {
-        return Arrays.asList(builtins);
+        return builtins;
     }
 }