diff -r 7d2478b04e95 -r 7aa1b3d6ff8f src/hotspot/share/jfr/recorder/stacktrace/jfrStackTraceRepository.hpp
--- a/src/hotspot/share/jfr/recorder/stacktrace/jfrStackTraceRepository.hpp	Sun Aug 25 10:12:57 2019 +0200
+++ b/src/hotspot/share/jfr/recorder/stacktrace/jfrStackTraceRepository.hpp	Sun Aug 25 13:27:54 2019 +0200
@@ -55,6 +55,8 @@
   bool initialize();
   static void destroy();
 
+  bool is_modified() const;
+
   size_t write_impl(JfrChunkWriter& cw, bool clear);
   static void write_metadata(JfrCheckpointWriter& cpw);
   traceid write(JfrCheckpointWriter& cpw, traceid id, unsigned int hash);