kconfig: nconf: get rid of (void) casts from wattrset() calls

This reverts commit 10175ba65f ("nconfig: Silence unused return values
from wattrset").

With this patch applied, recent GCC versions can cleanly build nconf
without "value computed is not used" warnings.

The wattrset() used to be implemented as a macro, like this:

  #define wattrset(win,at) \
          (NCURSES_OK_ADDR(win) \
            ? ((win)->_attrs = NCURSES_CAST(attr_t, at), \
               OK) \
            : ERR)

The GCC bugzilla [1] reported a false-positive -Wunused-value warning
in a similar test case. It was fixed by GCC 4.4.1.

Let's revert that commit, and see if somebody will claim the issue.

[1]: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=39889

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

scripts/kconfig/nconf.c

@@ -370,18 +370,18 @@ static void print_function_line(void)
 	int lines = getmaxy(stdscr);
 
 	for (i = 0; i < function_keys_num; i++) {
-		(void) wattrset(main_window, attributes[FUNCTION_HIGHLIGHT]);
+		wattrset(main_window, attributes[FUNCTION_HIGHLIGHT]);
 		mvwprintw(main_window, lines-3, offset,
 				"%s",
 				function_keys[i].key_str);
-		(void) wattrset(main_window, attributes[FUNCTION_TEXT]);
+		wattrset(main_window, attributes[FUNCTION_TEXT]);
 		offset += strlen(function_keys[i].key_str);
 		mvwprintw(main_window, lines-3,
 				offset, "%s",
 				function_keys[i].func);
 		offset += strlen(function_keys[i].func) + skip;
 	}
-	(void) wattrset(main_window, attributes[NORMAL]);
+	wattrset(main_window, attributes[NORMAL]);
 }
 
 /* help */
@@ -954,16 +954,16 @@ static void show_menu(const char *prompt, const char *instructions,
 	current_instructions = instructions;
 
 	clear();
-	(void) wattrset(main_window, attributes[NORMAL]);
+	wattrset(main_window, attributes[NORMAL]);
 	print_in_middle(stdscr, 1, 0, getmaxx(stdscr),
 			menu_backtitle,
 			attributes[MAIN_HEADING]);
 
-	(void) wattrset(main_window, attributes[MAIN_MENU_BOX]);
+	wattrset(main_window, attributes[MAIN_MENU_BOX]);
 	box(main_window, 0, 0);
-	(void) wattrset(main_window, attributes[MAIN_MENU_HEADING]);
+	wattrset(main_window, attributes[MAIN_MENU_HEADING]);
 	mvwprintw(main_window, 0, 3, " %s ", prompt);
-	(void) wattrset(main_window, attributes[NORMAL]);
+	wattrset(main_window, attributes[NORMAL]);
 
 	set_menu_items(curses_menu, curses_menu_items);
 

scripts/kconfig/nconf.gui.c

@@ -167,7 +167,7 @@ void print_in_middle(WINDOW *win,
 	length = strlen(string);
 	temp = (width - length) / 2;
 	x = startx + (int)temp;
-	(void) wattrset(win, color);
+	wattrset(win, color);
 	mvwprintw(win, y, x, "%s", string);
 	refresh();
 }
@@ -297,11 +297,11 @@ int btn_dialog(WINDOW *main_window, const char *msg, int btn_num, ...)
 	set_menu_fore(menu, attributes[DIALOG_MENU_FORE]);
 	set_menu_back(menu, attributes[DIALOG_MENU_BACK]);
 
-	(void) wattrset(win, attributes[DIALOG_BOX]);
+	wattrset(win, attributes[DIALOG_BOX]);
 	box(win, 0, 0);
 
 	/* print message */
-	(void) wattrset(msg_win, attributes[DIALOG_TEXT]);
+	wattrset(msg_win, attributes[DIALOG_TEXT]);
 	fill_window(msg_win, msg);
 
 	set_menu_win(menu, win);
@@ -405,16 +405,16 @@ int dialog_inputbox(WINDOW *main_window,
 	form_win = derwin(win, 1, prompt_width, prompt_lines+3, 2);
 	keypad(form_win, TRUE);
 
-	(void) wattrset(form_win, attributes[INPUT_FIELD]);
+	wattrset(form_win, attributes[INPUT_FIELD]);
 
-	(void) wattrset(win, attributes[INPUT_BOX]);
+	wattrset(win, attributes[INPUT_BOX]);
 	box(win, 0, 0);
-	(void) wattrset(win, attributes[INPUT_HEADING]);
+	wattrset(win, attributes[INPUT_HEADING]);
 	if (title)
 		mvwprintw(win, 0, 3, "%s", title);
 
 	/* print message */
-	(void) wattrset(prompt_win, attributes[INPUT_TEXT]);
+	wattrset(prompt_win, attributes[INPUT_TEXT]);
 	fill_window(prompt_win, prompt);
 
 	mvwprintw(form_win, 0, 0, "%*s", prompt_width, " ");
@@ -576,7 +576,7 @@ void show_scroll_win(WINDOW *main_window,
 
 	/* create the pad */
 	pad = newpad(total_lines+10, total_cols+10);
-	(void) wattrset(pad, attributes[SCROLLWIN_TEXT]);
+	wattrset(pad, attributes[SCROLLWIN_TEXT]);
 	fill_window(pad, text);
 
 	win_lines = min(total_lines+4, lines-2);
@@ -591,9 +591,9 @@ void show_scroll_win(WINDOW *main_window,
 	win = newwin(win_lines, win_cols, y, x);
 	keypad(win, TRUE);
 	/* show the help in the help window, and show the help panel */
-	(void) wattrset(win, attributes[SCROLLWIN_BOX]);
+	wattrset(win, attributes[SCROLLWIN_BOX]);
 	box(win, 0, 0);
-	(void) wattrset(win, attributes[SCROLLWIN_HEADING]);
+	wattrset(win, attributes[SCROLLWIN_HEADING]);
 	mvwprintw(win, 0, 3, " %s ", title);
 	panel = new_panel(win);