diff -r 44d60fc2dd8a -r e2dfab7beccb src/jdk.hotspot.agent/share/classes/sun/jvm/hotspot/debugger/linux/LinuxDebugger.java
--- a/src/jdk.hotspot.agent/share/classes/sun/jvm/hotspot/debugger/linux/LinuxDebugger.java	Mon Nov 04 13:58:33 2019 +0100
+++ b/src/jdk.hotspot.agent/share/classes/sun/jvm/hotspot/debugger/linux/LinuxDebugger.java	Mon Nov 04 22:31:59 2019 +0900
@@ -57,6 +57,7 @@
   public List         getThreadList();
   public List         getLoadObjectList();
   public ClosestSymbol lookup(long address);
+  public String demangle(String sym);
 
   // NOTE: this interface implicitly contains the following methods:
   // From the Debugger interface via JVMDebugger