--- a/src/hotspot/share/gc/z/zDriver.cpp	Tue Jul 02 12:24:26 2019 +0200
+++ b/src/hotspot/share/gc/z/zDriver.cpp	Mon Jun 10 13:04:12 2019 +0200
@@ -31,6 +31,7 @@
 #include "gc/z/zMessagePort.inline.hpp"
 #include "gc/z/zServiceability.hpp"
 #include "gc/z/zStat.hpp"
+#include "gc/z/zVerify.hpp"
 #include "logging/log.hpp"
 #include "memory/universe.hpp"
 #include "runtime/vmOperations.hpp"
@@ -86,6 +87,9 @@
     GCIdMark gc_id_mark(_gc_id);
     IsGCActiveMark gc_active_mark;
 
+    // Verify roots
+    ZVerify::roots_strong();
+
     // Execute operation
     _success = do_operation();
 
@@ -301,8 +305,14 @@
 
 void ZDriver::pause_verify() {
   if (VerifyBeforeGC || VerifyDuringGC || VerifyAfterGC) {
+    // Full verification
     VM_Verify op;
     VMThread::execute(&op);
+
+  } else if (ZVerifyRoots || ZVerifyObjects) {
+    // Limited verification
+    VM_ZVerifyOperation op;
+    VMThread::execute(&op);
   }
 }