Improve hashCode for closures

runtime/vm/bootstrap.cc

 // 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.
 
 #include "vm/bootstrap.h"
 
 #include "include/dart_api.h"
 
 #include "vm/bootstrap_natives.h"
 #include "vm/class_finalizer.h"
@@ skipping 214 matching lines @@
   // instances. This allows us to just finalize function types without going
   // through the hoops of trying to compile their scope class.
   ObjectStore* object_store = thread->isolate()->object_store();
   Zone* zone = thread->zone();
   Class& cls = Class::Handle(zone, object_store->closure_class());
   Compiler::CompileClass(cls);
 
 #if defined(DEBUG)
   // Verify that closure field offsets are identical in Dart and C++.
   const Array& fields = Array::Handle(zone, cls.fields());
-  ASSERT(fields.Length() == 4);
+  ASSERT(fields.Length() == 5);
   Field& field = Field::Handle(zone);
   field ^= fields.At(0);
   ASSERT(field.Offset() == Closure::instantiator_type_arguments_offset());
   field ^= fields.At(1);
   ASSERT(field.Offset() == Closure::function_type_arguments_offset());
   field ^= fields.At(2);
   ASSERT(field.Offset() == Closure::function_offset());
   field ^= fields.At(3);
   ASSERT(field.Offset() == Closure::context_offset());
+  field ^= fields.At(4);
+  ASSERT(field.Offset() == Closure::hash_offset());
 #endif  // defined(DEBUG)
 
   // Eagerly compile Bool class, bool constants are used from within compiler.
   cls = object_store->bool_class();
   Compiler::CompileClass(cls);
 }
 
 static RawError* BootstrapFromSource(Thread* thread) {
   Isolate* isolate = thread->isolate();
   Zone* zone = thread->zone();
@@ skipping 118 matching lines @@
       lib.Register(thread);
       isolate->object_store()->set_bootstrap_library(id, lib);
     }
   }
 
   return (kernel_program == NULL) ? BootstrapFromSource(thread)
                                   : BootstrapFromKernel(thread, kernel_program);
 }
 
 }  // namespace dart