--- a/src/hotspot/share/gc/shenandoah/shenandoahHeap.cpp	Thu May 02 06:33:28 2019 -0700
+++ b/src/hotspot/share/gc/shenandoah/shenandoahHeap.cpp	Thu May 02 09:49:52 2019 -0400
@@ -1487,8 +1487,13 @@
   if (!cancelled_gc()) {
     concurrent_mark()->finish_mark_from_roots(/* full_gc = */ false);
 
-    if (has_forwarded_objects()) {
-      concurrent_mark()->update_roots(ShenandoahPhaseTimings::update_roots);
+    // Degen may be caused by failed evacuation of roots
+    if (is_degenerated_gc_in_progress() && has_forwarded_objects()) {
+      concurrent_mark()->update_roots(ShenandoahPhaseTimings::degen_gc_update_roots);
+    }
+
+    if (ShenandoahVerify) {
+      verifier()->verify_roots_no_forwarded();
     }
 
     stop_concurrent_marking();
@@ -1540,6 +1545,7 @@
       }
 
       if (ShenandoahVerify) {
+        verifier()->verify_roots_no_forwarded();
         verifier()->verify_during_evacuation();
       }
     } else {
@@ -2176,8 +2182,8 @@
   assert(!cancelled_gc(), "Should have been done right before");
 
   concurrent_mark()->update_roots(is_degenerated_gc_in_progress() ?
-                                 ShenandoahPhaseTimings::degen_gc_update_roots:
-                                 ShenandoahPhaseTimings::final_update_refs_roots);
+                                  ShenandoahPhaseTimings::degen_gc_update_roots:
+                                  ShenandoahPhaseTimings::final_update_refs_roots);
 
   ShenandoahGCPhase final_update_refs(ShenandoahPhaseTimings::final_update_refs_recycle);
 
@@ -2186,6 +2192,7 @@
   set_update_refs_in_progress(false);
 
   if (ShenandoahVerify) {
+    verifier()->verify_roots_no_forwarded();
     verifier()->verify_after_updaterefs();
   }