Use PassiveObject were possible.

runtime/vm/compiler.cc

Index: runtime/vm/compiler.cc
===================================================================
--- runtime/vm/compiler.cc	(revision 39611)
+++ runtime/vm/compiler.cc	(working copy)
@@ -968,7 +968,7 @@
 
     // Invoke the function to evaluate the expression.
     const Function& initializer = parsed_function->function();
-    const Object& result = Object::Handle(
+    const Object& result = PassiveObject::Handle(
         DartEntry::InvokeFunction(initializer, Object::empty_array()));
     return result.raw();
   } else {
@@ -1026,12 +1026,12 @@
     // Non-optimized code generator.
     CompileParsedFunctionHelper(parsed_function, false, Isolate::kNoDeoptId);
 
-    const Object& result = Object::Handle(
+    const Object& result = PassiveObject::Handle(
         DartEntry::InvokeFunction(func, Object::empty_array()));
     return result.raw();
   } else {
     const Object& result =
-      Object::Handle(isolate->object_store()->sticky_error());
+      PassiveObject::Handle(isolate->object_store()->sticky_error());
     isolate->object_store()->clear_sticky_error();
     return result.raw();
   }