Visit encountered JSWeakCollection list during scavenging.

src/heap.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "v8.h"
 
 #include "accessors.h"
 #include "api.h"
 #include "bootstrapper.h"
 #include "codegen.h"
@@ skipping 127 matching lines @@
   max_semi_space_size_ = reserved_semispace_size_ = V8_MAX_SEMISPACE_SIZE;
 #endif
 
   // Ensure old_generation_size_ is a multiple of kPageSize.
   ASSERT(MB >= Page::kPageSize);
 
   memset(roots_, 0, sizeof(roots_[0]) * kRootListLength);
   set_native_contexts_list(NULL);
   set_array_buffers_list(Smi::FromInt(0));
   set_allocation_sites_list(Smi::FromInt(0));
+  set_encountered_weak_collections(Smi::FromInt(0));
   // Put a dummy entry in the remembered pages so we can find the list the
   // minidump even if there are no real unmapped pages.
   RememberUnmappedPage(NULL, false);
 
   ClearObjectStats(true);
 }
 
 
 intptr_t Heap::Capacity() {
   if (!HasBeenSetUp()) return 0;
@@ skipping 1343 matching lines @@
        heap_object = js_global_property_cell_iterator.Next()) {
     if (heap_object->IsPropertyCell()) {
       PropertyCell* cell = PropertyCell::cast(heap_object);
       Address value_address = cell->ValueAddress();
       scavenge_visitor.VisitPointer(reinterpret_cast<Object**>(value_address));
       Address type_address = cell->TypeAddress();
       scavenge_visitor.VisitPointer(reinterpret_cast<Object**>(type_address));
     }
   }
 
+  // Copy objects reachable from the encountered weak collections list.
+  scavenge_visitor.VisitPointer(&encountered_weak_collections_);
+
   // Copy objects reachable from the code flushing candidates list.
   MarkCompactCollector* collector = mark_compact_collector();
   if (collector->is_code_flushing_enabled()) {
     collector->code_flusher()->IteratePointersToFromSpace(&scavenge_visitor);
   }
 
   new_space_front = DoScavenge(&scavenge_visitor, new_space_front);
 
   while (isolate()->global_handles()->IterateObjectGroups(
       &scavenge_visitor, &IsUnscavengedHeapObject)) {
@@ skipping 4896 matching lines @@
       static_cast<int>(object_sizes_last_time_[index]));
   CODE_AGE_LIST_COMPLETE(ADJUST_LAST_TIME_OBJECT_COUNT)
 #undef ADJUST_LAST_TIME_OBJECT_COUNT
 
   MemCopy(object_counts_last_time_, object_counts_, sizeof(object_counts_));
   MemCopy(object_sizes_last_time_, object_sizes_, sizeof(object_sizes_));
   ClearObjectStats();
 }
 
 } }  // namespace v8::internal