--- a/langtools/src/share/classes/com/sun/tools/javac/tree/JCTree.java	Tue Oct 15 22:15:35 2013 +0200
+++ b/langtools/src/share/classes/com/sun/tools/javac/tree/JCTree.java	Tue Oct 15 15:57:13 2013 -0700
@@ -2359,6 +2359,7 @@
         public JCExpression underlyingType;
 
         protected JCAnnotatedType(List<JCAnnotation> annotations, JCExpression underlyingType) {
+            Assert.check(annotations != null && annotations.nonEmpty());
             this.annotations = annotations;
             this.underlyingType = underlyingType;
         }