--- old/src/hotspot/share/gc/shenandoah/shenandoahRootProcessor.cpp	2019-06-12 11:28:19.489231453 -0400
+++ new/src/hotspot/share/gc/shenandoah/shenandoahRootProcessor.cpp	2019-06-12 11:28:19.155231124 -0400
@@ -130,10 +130,16 @@
   ClassLoaderDataGraph::clear_claimed_marks();
 }
 
-void ShenandoahClassLoaderDataRoots::clds_do(CLDClosure* strong_clds, CLDClosure* weak_clds, uint worker_id) {
+void ShenandoahClassLoaderDataRoots::always_strong_cld_do(CLDClosure* clds, uint worker_id) {
   ShenandoahWorkerTimings* worker_times = ShenandoahHeap::heap()->phase_timings()->worker_times();
   ShenandoahWorkerTimingsTracker timer(worker_times, ShenandoahPhaseTimings::CLDGRoots, worker_id);
-  ClassLoaderDataGraph::roots_cld_do(strong_clds, weak_clds);
+  ClassLoaderDataGraph::always_strong_cld_do(clds);
+}
+
+void ShenandoahClassLoaderDataRoots::cld_do(CLDClosure* clds, uint worker_id) {
+  ShenandoahWorkerTimings* worker_times = ShenandoahHeap::heap()->phase_timings()->worker_times();
+  ShenandoahWorkerTimingsTracker timer(worker_times, ShenandoahPhaseTimings::CLDGRoots, worker_id);
+  ClassLoaderDataGraph::cld_do(clds);
 }
 
 ShenandoahRootProcessor::ShenandoahRootProcessor(ShenandoahPhaseTimings::Phase phase) :
@@ -165,7 +171,7 @@
   _jni_roots.oops_do(oops, worker_id);
 
   _thread_roots.oops_do(oops, NULL, worker_id);
-  _cld_roots.clds_do(&clds, &clds, worker_id);
+  _cld_roots.cld_do(&clds, worker_id);
   _code_roots.code_blobs_do(&blobsCl, worker_id);
 
   _weak_roots.oops_do<AlwaysTrueClosure, OopClosure>(&always_true, oops, worker_id);
@@ -195,7 +201,7 @@
   _jni_roots.oops_do(oops, worker_id);
 
   _thread_roots.oops_do(oops, NULL, worker_id);
-  _cld_roots.clds_do(&adjust_cld_closure, NULL, worker_id);
+  _cld_roots.cld_do(&adjust_cld_closure, worker_id);
   _code_roots.code_blobs_do(&adjust_code_closure, worker_id);
 
   _weak_roots.oops_do<AlwaysTrueClosure, OopClosure>(&always_true, oops, worker_id);
--- old/src/hotspot/share/gc/shenandoah/shenandoahRootProcessor.hpp	2019-06-12 11:28:20.280232231 -0400
+++ new/src/hotspot/share/gc/shenandoah/shenandoahRootProcessor.hpp	2019-06-12 11:28:19.939231896 -0400
@@ -112,7 +112,8 @@
 public:
   ShenandoahClassLoaderDataRoots();
 
-  void clds_do(CLDClosure* strong_clds, CLDClosure* weak_clds, uint worker_id);
+  void always_strong_cld_do(CLDClosure* clds, uint worker_id);
+  void cld_do(CLDClosure* clds, uint worker_id);
 };
 
 class ShenandoahRootProcessor : public StackObj {
--- old/src/hotspot/share/gc/shenandoah/shenandoahRootProcessor.inline.hpp	2019-06-12 11:28:21.085233024 -0400
+++ new/src/hotspot/share/gc/shenandoah/shenandoahRootProcessor.inline.hpp	2019-06-12 11:28:20.706232651 -0400
@@ -100,7 +100,13 @@
 
   _serial_roots.oops_do(oops, worker_id);
   _jni_roots.oops_do(oops, worker_id);
-  _cld_roots.clds_do(clds, clds, worker_id);
+
+  if (clds != NULL) {
+    _cld_roots.cld_do(clds, worker_id);
+  } else {
+    assert(ShenandoahHeap::heap()->is_concurrent_traversal_in_progress(), "Only possible with traversal GC");
+  }
+
   _thread_roots.threads_do(&tc_cl, worker_id);
 
   // With ShenandoahConcurrentScanCodeRoots, we avoid scanning the entire code cache here,
@@ -120,7 +126,7 @@
 
   _serial_roots.oops_do(oops, 0);
   _jni_roots.oops_do(oops, 0);
-  _cld_roots.clds_do(&clds, &clds, 0);
+  _cld_roots.cld_do(&clds, 0);
   _thread_roots.threads_do(&tc_cl, 0);
   _code_roots.code_blobs_do(&code, 0);
 }
@@ -134,7 +140,7 @@
 
   _serial_roots.oops_do(oops, 0);
   _jni_roots.oops_do(oops, 0);
-  _cld_roots.clds_do(&clds, NULL, 0);
+  _cld_roots.always_strong_cld_do(&clds, 0);
   _thread_roots.threads_do(&tc_cl, 0);
 }
 
@@ -146,7 +152,7 @@
 
   _serial_roots.oops_do(oops, worker_id);
   _jni_roots.oops_do(oops, worker_id);
-  _cld_roots.clds_do(clds, NULL, worker_id);
+  _cld_roots.always_strong_cld_do(clds, worker_id);
   _thread_roots.threads_do(&tc_cl, worker_id);
 }
 
@@ -154,13 +160,12 @@
 void ShenandoahRootUpdater::roots_do(uint worker_id, IsAlive* is_alive, KeepAlive* keep_alive) {
   CodeBlobToOopClosure update_blobs(keep_alive, CodeBlobToOopClosure::FixRelocations);
   CLDToOopClosure clds(keep_alive, ClassLoaderData::_claim_strong);
-  CLDToOopClosure* weak_clds = ShenandoahHeap::heap()->unload_classes() ? NULL : &clds;
 
   _serial_roots.oops_do(keep_alive, worker_id);
   _jni_roots.oops_do(keep_alive, worker_id);
 
   _thread_roots.oops_do(keep_alive, NULL, worker_id);
-  _cld_roots.clds_do(&clds, weak_clds, worker_id);
+  _cld_roots.cld_do(&clds, worker_id);
 
   if(_update_code_cache) {
     _code_roots.code_blobs_do(&update_blobs, worker_id);