Fix

velox/type/Subfield.h

@@ -29,8 +29,13 @@ enum SubfieldKind {
   kLongSubscript
 };
 
-// Contains field name separators to use in Tokenizer.
+// Contains field name separators to be used in Tokenizer.
 struct Separators {
+  static const std::shared_ptr<const Separators>& default() {
+    static const std::shared_ptr<const Separators> instance{new Separators()};
+    return instance;
+  }
+
   bool isSeparator(char c) const {
     return (
         c == closeBracket || c == dot || c == openBracket || c == quote ||
@@ -213,8 +218,7 @@ class Subfield {
   // Separators: the customized separators to tokenize field name.
   explicit Subfield(
       const std::string& path,
-      const std::shared_ptr<Separators>& separators =
-          std::make_shared<Separators>());
+      const std::shared_ptr<Separators>& separators = Separators::default());
 
   explicit Subfield(std::vector<std::unique_ptr<PathElement>>&& path);