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runtime/gc_vlhgc/CopyForwardScheme.cpp

@@ -2286,6 +2286,12 @@ MMINLINE void
 MM_CopyForwardScheme::scanOwnableSynchronizerObjectSlots(MM_EnvironmentVLHGC *env, MM_AllocationContextTarok *reservingContext, J9Object *objectPtr, ScanReason reason)
 {
 	if (scanMixedObjectSlots(env, reservingContext, objectPtr, reason)) {
+		/*
+		 * If object has been scanned without triggering abort add it to the list here.
+		 * If object scan triggered abort, it has been added to work packet
+		 * and is going to be rescanned again. It should not be added to the list here
+		 * to prevent duplication during second scan.
+		 */
 		if (SCAN_REASON_COPYSCANCACHE == reason) {
 			addOwnableSynchronizerObjectInList(env, objectPtr);
 		} else if (SCAN_REASON_PACKET == reason) {