diff --git a/plugins/android-compiler-plugin/src/org/jetbrains/kotlin/android/synthetic/diagnostic/AndroidExtensionPropertiesCallChecked.kt b/plugins/android-compiler-plugin/src/org/jetbrains/kotlin/android/synthetic/diagnostic/AndroidExtensionPropertiesCallChecked.kt
index 2214a43b446..390d7cd89ab 100644
--- a/plugins/android-compiler-plugin/src/org/jetbrains/kotlin/android/synthetic/diagnostic/AndroidExtensionPropertiesCallChecked.kt
+++ b/plugins/android-compiler-plugin/src/org/jetbrains/kotlin/android/synthetic/diagnostic/AndroidExtensionPropertiesCallChecked.kt
@@ -23,6 +23,7 @@ import org.jetbrains.kotlin.resolve.calls.checkers.CallChecker
 import org.jetbrains.kotlin.resolve.calls.context.BasicCallResolutionContext
 import org.jetbrains.kotlin.resolve.calls.model.ResolvedCall
 import org.jetbrains.kotlin.resolve.constants.StringValue
+import org.jetbrains.kotlin.android.synthetic.diagnostic.ErrorsAndroid.*
 
 public class AndroidExtensionPropertiesCallChecker : CallChecker {
     override fun <F : CallableDescriptor> check(resolvedCall: ResolvedCall<F>, context: BasicCallResolutionContext) {
@@ -39,7 +40,9 @@ public class AndroidExtensionPropertiesCallChecker : CallChecker {
             it.name.asString() == SyntheticFileGenerator.INVALID_WIDGET_TYPE_ANNOTATION_TYPE_PARAMETER
         }.values().firstOrNull() as? StringValue ?: return
 
-        context.trace.report(ErrorsAndroid.SYNTHETIC_INVALID_WIDGET_TYPE.on(expression, type.value))
+        val erroneousType = type.value
+        val warning = if (erroneousType.contains('.')) SYNTHETIC_UNRESOLVED_WIDGET_TYPE else SYNTHETIC_INVALID_WIDGET_TYPE
+        context.trace.report(warning.on(expression, erroneousType))
     }
 
 }
\ No newline at end of file
diff --git a/plugins/android-compiler-plugin/src/org/jetbrains/kotlin/android/synthetic/diagnostic/DefaultErrorMessagesAndroid.kt b/plugins/android-compiler-plugin/src/org/jetbrains/kotlin/android/synthetic/diagnostic/DefaultErrorMessagesAndroid.kt
index 7ea2c7099d3..853953d8c20 100644
--- a/plugins/android-compiler-plugin/src/org/jetbrains/kotlin/android/synthetic/diagnostic/DefaultErrorMessagesAndroid.kt
+++ b/plugins/android-compiler-plugin/src/org/jetbrains/kotlin/android/synthetic/diagnostic/DefaultErrorMessagesAndroid.kt
@@ -29,6 +29,9 @@ public class DefaultErrorMessagesAndroid : DefaultErrorMessages.Extension {
             MAP.put(ErrorsAndroid.SYNTHETIC_INVALID_WIDGET_TYPE,
                     "Widget has an invalid type ''{0}''. Please specify the fully qualified widget class name in XML",
                     Renderers.TO_STRING)
+            MAP.put(ErrorsAndroid.SYNTHETIC_UNRESOLVED_WIDGET_TYPE,
+                    "Widget has an unresolved type ''{0}'', and thus it was upcasted to ''android.view.View''.",
+                    Renderers.TO_STRING)
         }
     }
 
diff --git a/plugins/android-compiler-plugin/src/org/jetbrains/kotlin/android/synthetic/diagnostic/ErrorsAndroid.java b/plugins/android-compiler-plugin/src/org/jetbrains/kotlin/android/synthetic/diagnostic/ErrorsAndroid.java
index a67f3634ca5..a238baf8d42 100644
--- a/plugins/android-compiler-plugin/src/org/jetbrains/kotlin/android/synthetic/diagnostic/ErrorsAndroid.java
+++ b/plugins/android-compiler-plugin/src/org/jetbrains/kotlin/android/synthetic/diagnostic/ErrorsAndroid.java
@@ -24,6 +24,7 @@ import static org.jetbrains.kotlin.diagnostics.Severity.WARNING;
 
 public interface ErrorsAndroid {
     DiagnosticFactory1<JetExpression, String> SYNTHETIC_INVALID_WIDGET_TYPE = DiagnosticFactory1.create(WARNING);
+    DiagnosticFactory1<JetExpression, String> SYNTHETIC_UNRESOLVED_WIDGET_TYPE = DiagnosticFactory1.create(WARNING);
 
     @SuppressWarnings("UnusedDeclaration")
     Object _initializer = new Object() {