diff --git a/compiler/frontend/src/org/jetbrains/jet/lang/resolve/ScriptBodyResolver.java b/compiler/frontend/src/org/jetbrains/jet/lang/resolve/ScriptBodyResolver.java
index 1b8570a7dcc..382f5e3a052 100644
--- a/compiler/frontend/src/org/jetbrains/jet/lang/resolve/ScriptBodyResolver.java
+++ b/compiler/frontend/src/org/jetbrains/jet/lang/resolve/ScriptBodyResolver.java
@@ -22,10 +22,7 @@ import org.jetbrains.jet.lang.descriptors.ScriptDescriptor;
 import org.jetbrains.jet.lang.descriptors.ScriptDescriptorImpl;
 import org.jetbrains.jet.lang.descriptors.SimpleFunctionDescriptor;
 import org.jetbrains.jet.lang.descriptors.impl.PropertyDescriptorImpl;
-import org.jetbrains.jet.lang.psi.JetDeclaration;
-import org.jetbrains.jet.lang.psi.JetNamedFunction;
-import org.jetbrains.jet.lang.psi.JetProperty;
-import org.jetbrains.jet.lang.psi.JetScript;
+import org.jetbrains.jet.lang.psi.*;
 import org.jetbrains.jet.lang.resolve.calls.autocasts.DataFlowInfo;
 import org.jetbrains.jet.lang.resolve.scopes.WritableScope;
 import org.jetbrains.jet.lang.types.ErrorUtils;
@@ -82,9 +79,13 @@ public class ScriptBodyResolver {
             BindingContext bindingContext = trace.getBindingContext();
             for (JetDeclaration jetDeclaration : declaration.getDeclarations()) {
                 if (jetDeclaration instanceof JetProperty) {
+                    if (!shouldBeScriptClassMember(jetDeclaration)) continue;
+
                     properties.add((PropertyDescriptorImpl) bindingContext.get(BindingContext.VARIABLE, jetDeclaration));
                 }
                 else if (jetDeclaration instanceof JetNamedFunction) {
+                    if (!shouldBeScriptClassMember(jetDeclaration)) continue;
+
                     SimpleFunctionDescriptor function = bindingContext.get(BindingContext.FUNCTION, jetDeclaration);
                     assert function != null;
                     functions.add(function.copy(descriptor.getClassDescriptor(), function.getModality(), function.getVisibility(),
@@ -96,4 +97,11 @@ public class ScriptBodyResolver {
         }
     }
 
+    public static boolean shouldBeScriptClassMember(@NotNull JetDeclaration declaration) {
+        // To avoid the necessity to always analyze the whole body of a script even if just its class descriptor is needed
+        // we only add those vals, vars and funs that have explicitly specified return types
+        // (or implicit Unit for function with block body)
+        return declaration instanceof JetCallableDeclaration && ((JetCallableDeclaration) declaration).getReturnTypeRef() != null ||
+               declaration instanceof JetNamedFunction && ((JetNamedFunction) declaration).hasBlockBody();
+    }
 }
diff --git a/compiler/testData/codegen/script/fibwp.lang.kt b/compiler/testData/codegen/script/fibwp.lang.kt
index 5b0d322f7a0..2da99751f02 100644
--- a/compiler/testData/codegen/script/fibwp.lang.kt
+++ b/compiler/testData/codegen/script/fibwp.lang.kt
@@ -7,5 +7,5 @@ fun fib(n: Int): Int {
     return v
 }
 
-val result = fib(num)
+val result: Int = fib(num)
 12
\ No newline at end of file