diff -r 2557b27d1f1c -r 5ed5dd2ee5fe langtools/src/share/classes/com/sun/tools/javac/util/RichDiagnosticFormatter.java
--- a/langtools/src/share/classes/com/sun/tools/javac/util/RichDiagnosticFormatter.java	Thu Jul 04 10:41:08 2013 +0100
+++ b/langtools/src/share/classes/com/sun/tools/javac/util/RichDiagnosticFormatter.java	Fri Jul 05 11:00:19 2013 +0100
@@ -303,8 +303,9 @@
                     conflicts.contains(s))) {
                     List<Name> l = List.nil();
                     Symbol s2 = s;
-                    while (s2.type.getEnclosingType().hasTag(CLASS)
-                            && s2.owner.kind == Kinds.TYP) {
+                    while (s2.type.hasTag(CLASS) &&
+                            s2.type.getEnclosingType().hasTag(CLASS) &&
+                            s2.owner.kind == Kinds.TYP) {
                         l = l.prepend(s2.getSimpleName());
                         s2 = s2.owner;
                     }