diff --git a/src/ir/IR.h b/src/ir/IR.h
index 5a9e312..6cfe95a 100644
--- a/src/ir/IR.h
+++ b/src/ir/IR.h
@@ -30,7 +30,7 @@ class Context {
   std::shared_ptr<Type> int32_;
   std::shared_ptr<Type> ptr_i32_;
   std::unordered_map<int, std::unique_ptr<ConstantInt>> const_ints_;
-  int temp_index_ = 0;
+  int temp_index_ = -1;
 };
 
 Context& DefaultContext();