diff --git a/compiler/cli/src/org/jetbrains/jet/cli/common/CLICompiler.java b/compiler/cli/src/org/jetbrains/jet/cli/common/CLICompiler.java
index cadbaf22d58..88dc62ee16c 100644
--- a/compiler/cli/src/org/jetbrains/jet/cli/common/CLICompiler.java
+++ b/compiler/cli/src/org/jetbrains/jet/cli/common/CLICompiler.java
@@ -86,7 +86,7 @@ public abstract class CLICompiler<A extends CompilerArguments, C extends Compile
      * based tools to customise their own plugins
      */
     //TODO: add parameter annotations when KT-1863 is resolved
-    protected void configureEnvironment(C configuration, A arguments) {
+    protected void configureEnvironment(@NotNull C configuration, @NotNull A arguments) {
         List<CompilerPlugin> plugins = arguments.getCompilerPlugins();
         configuration.getCompilerPlugins().addAll(plugins);
     }
diff --git a/compiler/cli/src/org/jetbrains/jet/cli/jvm/K2JVMCompiler.java b/compiler/cli/src/org/jetbrains/jet/cli/jvm/K2JVMCompiler.java
index cfed5c1b314..6cf5b743e6a 100644
--- a/compiler/cli/src/org/jetbrains/jet/cli/jvm/K2JVMCompiler.java
+++ b/compiler/cli/src/org/jetbrains/jet/cli/jvm/K2JVMCompiler.java
@@ -175,7 +175,7 @@ public class K2JVMCompiler extends CLICompiler<K2JVMCompilerArguments, K2JVMComp
 
 
     @Override
-    protected void configureEnvironment(K2JVMCompileEnvironmentConfiguration configuration, K2JVMCompilerArguments arguments) {
+    protected void configureEnvironment(@NotNull K2JVMCompileEnvironmentConfiguration configuration, @NotNull K2JVMCompilerArguments arguments) {
         super.configureEnvironment(configuration, arguments);
 
         if (configuration.getEnvironment().getCompilerDependencies().getRuntimeJar() != null) {
diff --git a/libraries/tools/kdoc/src/main/kotlin/org/jetbrains/kotlin/doc/KDocCompiler.kt b/libraries/tools/kdoc/src/main/kotlin/org/jetbrains/kotlin/doc/KDocCompiler.kt
index 0f4fd7badbf..4ac8589c638 100644
--- a/libraries/tools/kdoc/src/main/kotlin/org/jetbrains/kotlin/doc/KDocCompiler.kt
+++ b/libraries/tools/kdoc/src/main/kotlin/org/jetbrains/kotlin/doc/KDocCompiler.kt
@@ -22,7 +22,7 @@ fun main(args: Array<String?>): Unit {
  */
 class KDocCompiler() : K2JVMCompiler() {
 
-    protected override fun configureEnvironment(configuration : CompileEnvironmentConfiguration?, arguments : K2JVMCompilerArguments?) {
+    protected override fun configureEnvironment(configuration : K2JVMCompileEnvironmentConfiguration, arguments : K2JVMCompilerArguments) {
         super.configureEnvironment(configuration, arguments)
         val coreEnvironment = configuration?.getEnvironment()
         if (coreEnvironment != null) {