Throw illegal argument exception when

vm/snapshot.h

 // Copyright (c) 2012, 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.
 
 #ifndef VM_SNAPSHOT_H_
 #define VM_SNAPSHOT_H_
 
 #include "platform/assert.h"
 #include "vm/allocation.h"
 #include "vm/bitfield.h"
@@ skipping 464 matching lines @@
   void ArrayWriteTo(intptr_t object_id,
                     intptr_t array_kind,
                     intptr_t tags,
                     RawSmi* length,
                     RawAbstractTypeArguments* type_arguments,
                     RawObject* data[]);
 
   ObjectStore* object_store() const { return object_store_; }
 
  private:
+  class NoGCDuringSnapshotWriteScope : public ValueObject {
+   public:
+#if defined(DEBUG)
+    NoGCDuringSnapshotWriteScope() {
+      Isolate::Current()->IncrementNoGCScopeDepth();
+    }
+    ~NoGCDuringSnapshotWriteScope() {
+      Isolate::Current()->DecrementNoGCScopeDepth();
+    }
+    void Reset() const {
+      Isolate::Current()->ResetNoGCScopeDepth();
+    }
+#else  // defined(DEBUG)
+    NoGCDuringSnapshotWriteScope() {}
+    ~NoGCDuringSnapshotWriteScope() {}
+    void Reset() const {}
+#endif  // defined(DEBUG)
+   private:
+    DISALLOW_COPY_AND_ASSIGN(NoGCDuringSnapshotWriteScope);
+  };
+  void ThrowIllegalArgException(const NoGCDuringSnapshotWriteScope& no_gc,
+                                const char* msg);
+
   Snapshot::Kind kind_;
   ObjectStore* object_store_;  // Object store for common classes.
   ClassTable* class_table_;  // Class table for the class index to class lookup.
   GrowableArray<ForwardObjectNode*> forward_list_;
 
   friend class RawArray;
   friend class RawClass;
   friend class RawGrowableObjectArray;
   friend class RawImmutableArray;
   friend class RawJSRegExp;
@@ skipping 79 matching lines @@
  private:
   SnapshotWriter* writer_;
   bool as_references_;
 
   DISALLOW_COPY_AND_ASSIGN(SnapshotWriterVisitor);
 };
 
 }  // namespace dart
 
 #endif  // VM_SNAPSHOT_H_