Make Isolate::GetHeapStatistics robust against half-initialized isolates.

src/api.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 5953 matching lines @@
 
 
 void Isolate::Exit() {
   i::Isolate* isolate = reinterpret_cast<i::Isolate*>(this);
   isolate->Exit();
 }
 
 
 void Isolate::GetHeapStatistics(HeapStatistics* heap_statistics) {
   i::Isolate* isolate = reinterpret_cast<i::Isolate*>(this);
+  if (!isolate->IsInitialized()) {
+    // Isolate is unitialized thus heap is not configured yet.

[payer, 2013/03/27 10:23:52]

I think we do not need that comment since the code is self-explanatory.

+    heap_statistics->total_heap_size_ = 0;
+    heap_statistics->total_heap_size_executable_ = 0;
+    heap_statistics->total_physical_size_ = 0;
+    heap_statistics->used_heap_size_ = 0;
+    heap_statistics->heap_size_limit_ = 0;
+    return;
+  }
   i::Heap* heap = isolate->heap();
   heap_statistics->total_heap_size_ = heap->CommittedMemory();
   heap_statistics->total_heap_size_executable_ =
       heap->CommittedMemoryExecutable();
   heap_statistics->total_physical_size_ = heap->CommittedPhysicalMemory();
   heap_statistics->used_heap_size_ = heap->SizeOfObjects();
   heap_statistics->heap_size_limit_ = heap->MaxReserved();
 }
 
 
@@ skipping 1077 matching lines @@
 
   v->VisitPointers(blocks_.first(), first_block_limit_);
 
   for (int i = 1; i < blocks_.length(); i++) {
     v->VisitPointers(blocks_[i], &blocks_[i][kHandleBlockSize]);
   }
 }
 
 
 } }  // namespace v8::internal