--- old/src/hotspot/share/utilities/constantTag.cpp	2019-03-11 14:27:26.834354040 +0100
+++ new/src/hotspot/share/utilities/constantTag.cpp	2019-03-11 14:27:26.618354043 +0100
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1997, 2017, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1997, 2018, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -35,7 +35,7 @@
 #endif // PRODUCT
 
 BasicType constantTag::basic_type() const {
-  switch (_tag) {
+  switch (value()) {
     case JVM_CONSTANT_Integer :
       return T_INT;
     case JVM_CONSTANT_Float :
@@ -69,7 +69,7 @@
 
 
 jbyte constantTag::non_error_value() const {
-  switch (_tag) {
+  switch (value()) {
   case JVM_CONSTANT_UnresolvedClassInError:
     return JVM_CONSTANT_UnresolvedClass;
   case JVM_CONSTANT_MethodHandleInError:
@@ -79,13 +79,13 @@
   case JVM_CONSTANT_DynamicInError:
     return JVM_CONSTANT_Dynamic;
   default:
-    return _tag;
+    return value();
   }
 }
 
 
 jbyte constantTag::error_value() const {
-  switch (_tag) {
+  switch (value()) {
   case JVM_CONSTANT_UnresolvedClass:
     return JVM_CONSTANT_UnresolvedClassInError;
   case JVM_CONSTANT_MethodHandle:
@@ -106,6 +106,8 @@
       return "Invalid index";
     case JVM_CONSTANT_Class :
       return "Class";
+    case (JVM_CONSTANT_Class | (jbyte)JVM_CONSTANT_QDESC_BIT):
+      return "Q-Descriptor";
     case JVM_CONSTANT_Fieldref :
       return "Field";
     case JVM_CONSTANT_Methodref :