- Do not try to determine the address of Smis.

runtime/vm/scavenger.cc

 // Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/scavenger.h"
 
 #include "vm/dart.h"
 #include "vm/dart_api_state.h"
 #include "vm/isolate.h"
 #include "vm/object.h"
@@ skipping 305 matching lines @@
   }
   if (FLAG_verbose_gc) {
     OS::PrintErr("StoreBuffer: %d, %d (entries, dups)\n",
                  entries, duplicates);
   }
   StoreBufferBlock* block = isolate->store_buffer_block();
   entries = block->Count();
   duplicates = 0;
   for (intptr_t i = 0; i < entries; i++) {
     RawObject** pointer = reinterpret_cast<RawObject**>(block->At(i));
-    if (from_->Contains(RawObject::ToAddr(*pointer))) {
-      visitor->VisitPointer(pointer);
-    } else {
-      duplicates++;
+    RawObject* value = *pointer;
+    if (value->IsHeapObject()) {
+      if (from_->Contains(RawObject::ToAddr(value))) {
+        visitor->VisitPointer(pointer);
+      } else {
+        duplicates++;
+      }
     }
   }
   block->Reset();
   if (FLAG_verbose_gc) {
     OS::PrintErr("StoreBufferBlock: %d, %d (entries, dups)\n",
                  entries, duplicates);
   }
   // Done iterating through the store buffers.
   visitor->VisitingOldPointers(false);
 }
@@ skipping 176 matching lines @@
     OS::PrintErr(" done.\n");
   }
 
   count_++;
   // Done scavenging. Reset the marker.
   ASSERT(scavenging_);
   scavenging_ = false;
 }
 
 }  // namespace dart