| Index: src/heap/mark-compact.cc
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| diff --git a/src/heap/mark-compact.cc b/src/heap/mark-compact.cc
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| index 0f43ad956fb9e79b21af8449fdf1bc2b81cda2f2..b2ae93dec66b590e8f29aeb797c2b81f7b33aebd 100644
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| --- a/src/heap/mark-compact.cc
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| +++ b/src/heap/mark-compact.cc
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| @@ -1406,8 +1406,8 @@ class RootMarkingVisitor : public ObjectVisitor {
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|    void MarkObjectByPointer(Object** p) {
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|      if (!(*p)->IsHeapObject()) return;
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|  
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| -    // Replace flat cons strings in place.
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|      HeapObject* object = HeapObject::cast(*p);
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| +
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|      MarkBit mark_bit = Marking::MarkBitFrom(object);
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|      if (Marking::IsBlackOrGrey(mark_bit)) return;
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|  
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| 
 |