diff --git a/Android.mk b/Android.mk
index 0597666..544d8da 100644
--- a/Android.mk
+++ b/Android.mk
@@ -14,7 +14,7 @@
 
 LOCAL_PATH := $(call my-dir)
 
-libdbusBindingGenCFlags := -Wno-unused-parameter
+libdbusBindingGenCFlags := -Wall -Werror
 
 include $(CLEAR_VARS)
 LOCAL_MODULE := libdbus-binding-gen-host
diff --git a/chromeos-dbus-bindings/proxy_generator.cc b/chromeos-dbus-bindings/proxy_generator.cc
index 55c9eee..8c295ee 100644
--- a/chromeos-dbus-bindings/proxy_generator.cc
+++ b/chromeos-dbus-bindings/proxy_generator.cc
@@ -767,7 +767,7 @@
 
 // static
 void ProxyGenerator::AddMethodMock(const Interface::Method& method,
-                                   const string& interface_name,
+                                   const string& /* interface_name */,
                                    IndentedText* text) {
   DbusSignature signature;
   vector<string> arguments;
@@ -794,7 +794,7 @@
 
 // static
 void ProxyGenerator::AddAsyncMethodMock(const Interface::Method& method,
-                                        const string& interface_name,
+                                        const string& /* interface_name */,
                                         IndentedText* text) {
   DbusSignature signature;
   vector<string> arguments;
@@ -1137,6 +1137,22 @@
 void ProxyGenerator::ObjectManager::AddOnPropertyChanged(
     const std::vector<Interface>& interfaces,
     IndentedText* text) {
+  // If there are no interfaces with properties, comment out parameter
+  // names for OnPropertyChanged() to prevent compiler warnings on unused
+  // function parameters.
+  auto has_props = [](const Interface& itf) { return !itf.properties.empty(); };
+  auto itf_with_props = std::find_if(interfaces.begin(), interfaces.end(),
+                                     has_props);
+  if (itf_with_props == interfaces.end()) {
+    text->AddLineAndPushOffsetTo("void OnPropertyChanged("
+                                 "const dbus::ObjectPath& /* object_path */,",
+                                 1, '(');
+    text->AddLine("const std::string& /* interface_name */,");
+    text->AddLine("const std::string& /* property_name */) {}");
+    text->PopOffset();
+    text->AddBlankLine();
+    return;
+  }
   text->AddLineAndPushOffsetTo("void OnPropertyChanged("
                                "const dbus::ObjectPath& object_path,",
                                1, '(');
diff --git a/chromeos-dbus-bindings/proxy_generator_unittest.cc b/chromeos-dbus-bindings/proxy_generator_unittest.cc
index 4eda77c..728e977 100644
--- a/chromeos-dbus-bindings/proxy_generator_unittest.cc
+++ b/chromeos-dbus-bindings/proxy_generator_unittest.cc
@@ -1196,10 +1196,9 @@
   }
 
  private:
-  void OnPropertyChanged(const dbus::ObjectPath& object_path,
-                         const std::string& interface_name,
-                         const std::string& property_name) {
-  }
+  void OnPropertyChanged(const dbus::ObjectPath& /* object_path */,
+                         const std::string& /* interface_name */,
+                         const std::string& /* property_name */) {}
 
   void ObjectAdded(
       const dbus::ObjectPath& object_path,