diff --git a/include/tvm/ir/attrs.h b/include/tvm/ir/attrs.h
index f3b760715a61c..819aafa0281cd 100644
--- a/include/tvm/ir/attrs.h
+++ b/include/tvm/ir/attrs.h
@@ -230,7 +230,7 @@ class DictAttrs : public Attrs {
    * \param dict The attributes.
    * \return The dict attributes.
    */
-  TVM_DLL explicit DictAttrs(Map<String, ObjectRef> dict);
+  TVM_DLL explicit DictAttrs(Map<std::string, ObjectRef> dict);
 
   TVM_DEFINE_OBJECT_REF_METHODS(DictAttrs, Attrs, DictAttrsNode);
   TVM_DEFINE_OBJECT_REF_COW_METHOD(DictAttrsNode);
diff --git a/include/tvm/ir/function.h b/include/tvm/ir/function.h
index 5b9e0714e2023..00626e6d20a4f 100644
--- a/include/tvm/ir/function.h
+++ b/include/tvm/ir/function.h
@@ -188,7 +188,7 @@ inline TFunc WithAttr(TFunc func, const std::string& attr_key, ObjectRef attr_va
   if (node->attrs.defined()) {
     node->attrs.CopyOnWrite()->dict.Set(attr_key, attr_value);
   } else {
-    Map<String, ObjectRef> dict = {{attr_key, attr_value}};
+    Map<std::string, ObjectRef> dict = {{attr_key, attr_value}};
     node->attrs = DictAttrs(dict);
   }
   return func;
diff --git a/include/tvm/runtime/container.h b/include/tvm/runtime/container.h
index 86aca4ec122e5..e2f2453933a5b 100644
--- a/include/tvm/runtime/container.h
+++ b/include/tvm/runtime/container.h
@@ -569,7 +569,7 @@ inline String operator+(const std::string lhs, const String& rhs) {
 }
 
 inline std::ostream& operator<<(std::ostream& out, const String& input) {
-  out << input.operator std::string();
+  out.write(input.data(), input.size());
   return out;
 }
 
diff --git a/src/ir/attrs.cc b/src/ir/attrs.cc
index b8dbf78dcf7d8..edc81ae201b08 100644
--- a/src/ir/attrs.cc
+++ b/src/ir/attrs.cc
@@ -47,13 +47,9 @@ void DictAttrsNode::InitByPackedArgs(const runtime::TVMArgs& args, bool allow_un
 
 Array<AttrFieldInfo> DictAttrsNode::ListFieldInfo() const { return {}; }
 
-DictAttrs::DictAttrs(Map<String, ObjectRef> dict) {
+DictAttrs::DictAttrs(Map<std::string, ObjectRef> dict) {
   ObjectPtr<DictAttrsNode> n = make_object<DictAttrsNode>();
-  Map<std::string, ObjectRef> dict_copy;
-  for (auto iter : dict) {
-    dict_copy.Set(iter.first.operator std::string(), iter.second);
-  }
-  n->dict = std::move(dict_copy);
+  n->dict = std::move(dict);
   data_ = std::move(n);
 }