diff --git a/compiler/backend/src/org/jetbrains/jet/codegen/NamespaceCodegen.java b/compiler/backend/src/org/jetbrains/jet/codegen/NamespaceCodegen.java
index 562ff2c2204..cbce46a3719 100644
--- a/compiler/backend/src/org/jetbrains/jet/codegen/NamespaceCodegen.java
+++ b/compiler/backend/src/org/jetbrains/jet/codegen/NamespaceCodegen.java
@@ -111,6 +111,7 @@ public class NamespaceCodegen extends MemberCodegen {
 
     private void generate(JetFile file, boolean multiFile) {
         NamespaceDescriptor descriptor = state.getBindingContext().get(BindingContext.FILE_TO_NAMESPACE, file);
+        assert descriptor != null : "No namespace found for file " + file + " declared package: " + file.getPackageName();
         for (JetDeclaration declaration : file.getDeclarations()) {
             if (declaration instanceof JetProperty) {
                 final CodegenContext context = CodegenContext.STATIC.intoNamespace(descriptor);
diff --git a/compiler/backend/src/org/jetbrains/jet/codegen/context/CodegenContext.java b/compiler/backend/src/org/jetbrains/jet/codegen/context/CodegenContext.java
index 5fc931d2622..e26542628ca 100644
--- a/compiler/backend/src/org/jetbrains/jet/codegen/context/CodegenContext.java
+++ b/compiler/backend/src/org/jetbrains/jet/codegen/context/CodegenContext.java
@@ -135,7 +135,7 @@ public abstract class CodegenContext {
         return contextKind;
     }
 
-    public CodegenContext intoNamespace(NamespaceDescriptor descriptor) {
+    public CodegenContext intoNamespace(@NotNull NamespaceDescriptor descriptor) {
         return new NamespaceContext(descriptor, this, OwnerKind.NAMESPACE);
     }
 
diff --git a/compiler/backend/src/org/jetbrains/jet/codegen/context/NamespaceContext.java b/compiler/backend/src/org/jetbrains/jet/codegen/context/NamespaceContext.java
index c8a7e14954a..cf37a31beed 100644
--- a/compiler/backend/src/org/jetbrains/jet/codegen/context/NamespaceContext.java
+++ b/compiler/backend/src/org/jetbrains/jet/codegen/context/NamespaceContext.java
@@ -21,7 +21,7 @@ import org.jetbrains.jet.codegen.OwnerKind;
 import org.jetbrains.jet.lang.descriptors.NamespaceDescriptor;
 
 public class NamespaceContext extends CodegenContext {
-    public NamespaceContext(NamespaceDescriptor contextDescriptor, CodegenContext parent, @NotNull OwnerKind kind) {
+    public NamespaceContext(@NotNull NamespaceDescriptor contextDescriptor, CodegenContext parent, @NotNull OwnerKind kind) {
         super(contextDescriptor, kind, parent, null, null, null);
     }