Fix CreateFillerObjectAt() call for 64b platforms

src/heap/mark-compact.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 "src/heap/mark-compact.h"
 
 #include "src/base/atomicops.h"
 #include "src/base/bits.h"
 #include "src/base/sys-info.h"
 #include "src/code-stubs.h"
@@ skipping 239 matching lines @@
     Address limit = it != range.end() ? page->area_end() : space->top();
     CHECK(limit == space->top() || !page->Contains(space->top()));
     VerifyEvacuationOnPage(current, limit);
   }
 }
 
 void EvacuationVerifier::VerifyEvacuation(PagedSpace* space) {
   for (Page* p : *space) {
     if (p->IsEvacuationCandidate()) continue;
     if (p->Contains(space->top()))
-      heap_->CreateFillerObjectAt(space->top(), space->limit() - space->top(),
-                                  ClearRecordedSlots::kNo);
+      heap_->CreateFillerObjectAt(
+          space->top(), static_cast<int>(space->limit() - space->top()),
+          ClearRecordedSlots::kNo);
 
     VerifyEvacuationOnPage(p->area_start(), p->area_end());
   }
 }
 
 class FullEvacuationVerifier : public EvacuationVerifier {
  public:
   explicit FullEvacuationVerifier(Heap* heap) : EvacuationVerifier(heap) {}
 
   void Run() override {
@@ skipping 3897 matching lines @@
       // The target is always in old space, we don't have to record the slot in
       // the old-to-new remembered set.
       DCHECK(!heap()->InNewSpace(target));
       RecordRelocSlot(host, &rinfo, target);
     }
   }
 }
 
 }  // namespace internal
 }  // namespace v8