diff --git a/util/read.cpp b/util/read.cpp
index 3455ea3cf..65e8de999 100644
--- a/util/read.cpp
+++ b/util/read.cpp
@@ -20,10 +20,10 @@ class NullEventHandler : public YAML::EventHandler {
   void OnScalar(const Mark&, const std::string&, anchor_t,
                 const std::string&) override {}
   void OnSequenceStart(const Mark&, const std::string&, anchor_t,
-                       YAML::EmitterStyle::value style) override {}
+                       YAML::EmitterStyle::value) override {}
   void OnSequenceEnd() override {}
   void OnMapStart(const Mark&, const std::string&, anchor_t,
-                  YAML::EmitterStyle::value style) override {}
+                  YAML::EmitterStyle::value) override {}
   void OnMapEnd() override {}
 };
 
diff --git a/util/sandbox.cpp b/util/sandbox.cpp
index f21490e7a..cb39dba06 100644
--- a/util/sandbox.cpp
+++ b/util/sandbox.cpp
@@ -18,10 +18,10 @@ class NullEventHandler : public YAML::EventHandler {
   void OnScalar(const Mark&, const std::string&, anchor_t,
                 const std::string&) override {}
   void OnSequenceStart(const Mark&, const std::string&, anchor_t,
-                       YAML::EmitterStyle::value style) override {}
+                       YAML::EmitterStyle::value) override {}
   void OnSequenceEnd() override {}
   void OnMapStart(const Mark&, const std::string&, anchor_t,
-                  YAML::EmitterStyle::value style) override {}
+                  YAML::EmitterStyle::value) override {}
   void OnMapEnd() override {}
 };