In background compilation make a copy of Field in order to freeze its state

runtime/vm/flow_graph_builder.cc

Index: runtime/vm/flow_graph_builder.cc
diff --git a/runtime/vm/flow_graph_builder.cc b/runtime/vm/flow_graph_builder.cc
index 680ea93f4364c32353ee68b6e6439508dd37b958..25ea02afbb6226992512a8eb5ecd1bf340e1f9a8 100644
--- a/runtime/vm/flow_graph_builder.cc
+++ b/runtime/vm/flow_graph_builder.cc
@@ -2770,7 +2770,7 @@ void ValueGraphVisitor::VisitClosureCallNode(ClosureCallNode* node) {
 
 
 void EffectGraphVisitor::VisitInitStaticFieldNode(InitStaticFieldNode* node) {
-  Value* field = Bind(new(Z) ConstantInstr(node->field()));
+  Value* field = Bind(new(Z) ConstantInstr(*node->field().OriginalAsHandle()));
   AddInstruction(new(Z) InitStaticFieldInstr(field, node->field()));
 }
 
@@ -3733,7 +3733,8 @@ void EffectGraphVisitor::VisitLoadStaticFieldNode(LoadStaticFieldNode* node) {
         Instance::ZoneHandle(Z, node->field().StaticValue()), token_pos);
     return ReturnDefinition(result);
   }
-  Value* field_value = Bind(new(Z) ConstantInstr(node->field(), token_pos));
+  Value* field_value = Bind(new(Z) ConstantInstr(
+      *node->field().OriginalAsHandle(Z), token_pos));

[siva, 2016/02/25 23:38:32]

ditto comment.

[srdjan, 2016/02/26 00:40:42]

Resolved using Field::ZoneHandle

   LoadStaticFieldInstr* load =
       new(Z) LoadStaticFieldInstr(field_value, token_pos);
   ReturnDefinition(load);