Replaced UNUSED with [[maybe_unused]] where applicable

src/commandline_argv.cpp

@@ -76,11 +76,9 @@ std::vector<std::string> win32_read_argv(const std::string& input)
 
 #endif
 
-std::vector<std::string> read_argv(int argc, char** argv)
+std::vector<std::string> read_argv([[maybe_unused]] int argc, [[maybe_unused]] char** argv)
 {
 #ifdef _WIN32
-	UNUSED(argc);
-	UNUSED(argv);
 	// On Windows, argv is ANSI-encoded by default. Wesnoth absolutely needs to
 	// work with UTF-8 values in order to avoid losing or corrupting
 	// information from the command line.

src/desktop/open.cpp

@@ -43,7 +43,7 @@ static lg::log_domain log_desktop("desktop");
 
 namespace desktop {
 
-bool open_object(const std::string& path_or_url)
+bool open_object([[maybe_unused]] const std::string& path_or_url)
 {
 	LOG_DU << "open_object(): requested object: " << path_or_url << '\n';
 
@@ -88,7 +88,6 @@ bool open_object(const std::string& path_or_url)
 
 #else
 
-	UNUSED(path_or_url); // silence gcc's -Wunused-parameter
 	ERR_DU << "open_object(): unsupported platform" << std::endl;
 	return false;
 

src/filesystem.cpp

@@ -607,9 +607,7 @@ static bool is_path_relative_to_cwd(const std::string& str)
 
 void set_user_data_dir(std::string newprefdir)
 {
-	bool relative_ok = false;
-	// Not always but it can be unused in some configurations
-	UNUSED(relative_ok);
+	[[maybe_unused]] bool relative_ok = false;
 
 #ifdef PREFERENCES_DIR
 	if(newprefdir.empty()) {

src/gui/dialogs/lua_interpreter.cpp

@@ -221,9 +221,8 @@ class lua_interpreter::input_model {
 		} catch (...) { std::cerr << "Swallowed an exception when trying to write lua command line history\n";}
 	}
 #endif
-	void add_to_history (const std::string& str) {
+	void add_to_history ([[maybe_unused]] const std::string& str) {
 		prefix_ = "";
-		UNUSED(str);
 #ifdef HAVE_HISTORY
 		add_history(str.c_str());
 #endif
@@ -241,7 +240,7 @@ class lua_interpreter::input_model {
 		LOG_LUA << "updated prefix\n";
 	}
 
-	std::string search( int direction ) {
+	std::string search([[maybe_unused]] int direction ) {
 #ifdef HAVE_HISTORY
 		LOG_LUA << "searching in direction " << direction << " from position " << where_history() << "\n";
 
@@ -285,7 +284,6 @@ class lua_interpreter::input_model {
 
 		// reset, set history to the end and prefix_ to empty, and return the current prefix_ for the user to edit
 		end_of_history_ = true;
-		UNUSED(direction);
 		std::string temp = prefix_;
 		prefix_ = "";
 		return temp;
@@ -330,7 +328,7 @@ class lua_interpreter::input_model {
 	// Does history expansion in a command line. A return value of true indicates an error,
 	// the error message will be returned in the string argument. A return value of false
 	// indicates success and that execution should proceed.
-	bool do_history_expansion (std::string & cmd) {
+	bool do_history_expansion ([[maybe_unused]] std::string & cmd) {
 #ifdef HAVE_HISTORY
 		// Do history expansions
 		std::unique_ptr<char[]> cmd_cstr(new char[cmd.length()+1]);
@@ -349,7 +347,6 @@ class lua_interpreter::input_model {
 		cmd = expansion;
 		free(expansion);
 #endif
-		UNUSED(cmd);
 		return false;
 	}
 };

src/scripting/game_lua_kernel.cpp

@@ -1611,7 +1611,6 @@ int game_lua_kernel::impl_end_level_data_set(lua_State* L)
 static int impl_end_level_data_collect(lua_State* L)
 {
 	end_level_data* data = static_cast<end_level_data*>(lua_touserdata(L, 1));
-	UNUSED(data); // Suppress an erroneous MSVC warning (a destructor call doesn't count as a reference)
 	data->~end_level_data();
 	return 0;
 }

src/server/campaignd/server.cpp

@@ -705,7 +705,7 @@ void server::write_config()
 	DBG_CS << "... done\n";
 }
 
-void server::fire(const std::string& hook, const std::string& addon)
+void server::fire(const std::string& hook, [[maybe_unused]] const std::string& addon)
 {
 	const std::map<std::string, std::string>::const_iterator itor = hooks_.find(hook);
 	if(itor == hooks_.end()) {
@@ -718,7 +718,6 @@ void server::fire(const std::string& hook, const std::string& addon)
 	}
 
 #if defined(_WIN32)
-	UNUSED(addon);
 	ERR_CS << "Tried to execute a script on an unsupported platform\n";
 	return;
 #else

src/tests/test_config.cpp

@@ -256,24 +256,18 @@ BOOST_AUTO_TEST_CASE(test_variable_info)
 		BOOST_CHECK_EQUAL(variable_access_const("tag1[1].tag2.length", nonempty).as_scalar(), 3);
 		BOOST_CHECK_EQUAL(variable_access_const("tag1[1].tag2[2].atribute1", nonempty).as_scalar().to_int(), 88);
 		int count = 0;
-		for(const config& child : variable_access_const("tag1", nonempty).as_array()) {
-			// silences unused variable warning.
-			UNUSED(child);
+		for([[maybe_unused]] const config& child : variable_access_const("tag1", nonempty).as_array()) {
 			++count;
 		}
 		BOOST_CHECK_EQUAL(count, 3);
 		count = 0;
-		for(const config& child : variable_access_const("tag1.tag2", nonempty).as_array()) {
-			// silences unused variable warning.
-			UNUSED(child);
+		for([[maybe_unused]] const config& child : variable_access_const("tag1.tag2", nonempty).as_array()) {
 			++count;
 		}
 		BOOST_CHECK_EQUAL(count, 0);
 		count = 0;
 		// explicit indexes as range always return a one element range, whether they exist or not.
-		for(const config& child : variable_access_const("tag1.tag2[5]", nonempty).as_array()) {
-			// silences unused variable warning.
-			UNUSED(child);
+		for([[maybe_unused]] const config& child : variable_access_const("tag1.tag2[5]", nonempty).as_array()) {
 			++count;
 		}
 		BOOST_CHECK_EQUAL(count, 1);