--- old/src/hotspot/share/gc/g1/g1GCPhaseTimes.hpp	2019-02-27 10:34:47.013955567 +0100
+++ new/src/hotspot/share/gc/g1/g1GCPhaseTimes.hpp	2019-02-27 10:34:46.739947235 +0100
@@ -47,8 +47,7 @@
   enum GCParPhases {
     GCWorkerStart,
     ExtRootScan,
-    ExtRootScanSubPhasesStart,
-    ThreadRoots = ExtRootScanSubPhasesStart,
+    ThreadRoots,
     UniverseRoots,
     JNIRoots,
     ObjectSynchronizerRoots,
@@ -63,7 +62,6 @@
     WaitForStrongCLD,
     WeakCLDRoots,
     SATBFiltering,
-    ExtRootScanSubPhasesEnd = SATBFiltering,
     UpdateRS,
     ScanHCC,
     ScanRS,
@@ -83,6 +81,9 @@
     GCParPhasesSentinel
   };
 
+  static const GCParPhases ExtRootScanSubPhasesStart = ThreadRoots;
+  static const GCParPhases ExtRootScanSubPhasesEnd = SATBFiltering;
+
   enum GCScanRSWorkItems {
     ScanRSScannedCards,
     ScanRSClaimedCards,