diff --git a/compiler/cli/src/org/jetbrains/jet/compiler/CompileEnvironment.java b/compiler/cli/src/org/jetbrains/jet/compiler/CompileEnvironment.java
index b296d4cfb01..6aa2fe28e67 100644
--- a/compiler/cli/src/org/jetbrains/jet/compiler/CompileEnvironment.java
+++ b/compiler/cli/src/org/jetbrains/jet/compiler/CompileEnvironment.java
@@ -9,6 +9,7 @@ import com.intellij.psi.search.GlobalSearchScope;
 import com.intellij.util.Processor;
 import jet.modules.AllModules;
 import jet.modules.Module;
+import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 import org.jetbrains.jet.codegen.ClassFileFactory;
 import org.jetbrains.jet.codegen.GeneratedClassLoader;
@@ -67,6 +68,7 @@ public class CompileEnvironment {
         Disposer.dispose(myRootDisposable);
     }
 
+    @Nullable
     public static File getUnpackedRuntimePath() {
         URL url = CompileEnvironment.class.getClassLoader().getResource("jet/JetObject.class");
         if (url != null && url.getProtocol().equals("file")) {
@@ -75,6 +77,7 @@ public class CompileEnvironment {
         return null;
     }
 
+    @Nullable
     public static File getRuntimeJarPath() {
         URL url = CompileEnvironment.class.getClassLoader().getResource("jet/JetObject.class");
         if (url != null && url.getProtocol().equals("jar")) {
@@ -88,7 +91,7 @@ public class CompileEnvironment {
         ensureRuntime(myEnvironment);
     }
 
-    public static void ensureRuntime(JetCoreEnvironment env) {
+    public static void ensureRuntime(@NotNull JetCoreEnvironment env) {
         Project project = env.getProject();
         if (JavaPsiFacade.getInstance(project).findClass("java.lang.Object", GlobalSearchScope.allScope(project)) == null) {
             // TODO: prepend
@@ -102,6 +105,9 @@ public class CompileEnvironment {
                 kotlin = getUnpackedRuntimePath();
                 if (kotlin == null) kotlin = getRuntimeJarPath();
             }
+            if (kotlin == null) {
+                throw new IllegalStateException("kotlin runtime not found");
+            }
             env.addToClasspath(kotlin);
         }
     }
diff --git a/compiler/util/src/org/jetbrains/jet/plugin/compiler/PathUtil.java b/compiler/util/src/org/jetbrains/jet/plugin/compiler/PathUtil.java
index 5d15677d1e8..6a0abaecb8b 100644
--- a/compiler/util/src/org/jetbrains/jet/plugin/compiler/PathUtil.java
+++ b/compiler/util/src/org/jetbrains/jet/plugin/compiler/PathUtil.java
@@ -7,6 +7,7 @@ import com.intellij.openapi.application.PathManager;
 import com.intellij.openapi.vfs.VirtualFile;
 import com.intellij.openapi.vfs.VirtualFileManager;
 import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
 
 import java.io.File;
 import java.util.ArrayList;
@@ -46,6 +47,7 @@ public class PathUtil {
         return null;
     }
 
+    @Nullable
     public static File getDefaultRuntimePath() {
         File compilerPath = getDefaultCompilerPath();
         if (compilerPath == null) return null;