diff --git a/src/hotspot/share/gc/z/zRelocate.cpp b/src/hotspot/share/gc/z/zRelocate.cpp
index 19e8109..cd9dd5c 100644
--- a/src/hotspot/share/gc/z/zRelocate.cpp
+++ b/src/hotspot/share/gc/z/zRelocate.cpp
@@ -41,7 +41,7 @@ private:
 public:
   ZRelocateRootsTask() :
       ZTask("ZRelocateRootsTask"),
-      _roots() {}
+      _roots(false) {}
 
   virtual void work() {
     // During relocation we need to visit the JVMTI