Use ATTR_UNUSED instead of void casting

CRT.c

@@ -652,8 +652,7 @@ int CRT_scrollWheelVAmount = 10;
 ColorScheme CRT_colorScheme = COLORSCHEME_DEFAULT;
 
 ATTR_NORETURN
-static void CRT_handleSIGTERM(int sgn) {
-   (void) sgn;
+static void CRT_handleSIGTERM(ATTR_UNUSED int sgn) {
    CRT_done();
    _exit(0);
 }

HostnameMeter.c

@@ -19,8 +19,7 @@ static const int HostnameMeter_attributes[] = {
    HOSTNAME
 };
 
-static void HostnameMeter_updateValues(Meter* this, char* buffer, size_t size) {
-   (void) this;
+static void HostnameMeter_updateValues(ATTR_UNUSED Meter* this, char* buffer, size_t size) {
    gethostname(buffer, size - 1);
 }
 

Meter.c

@@ -387,9 +387,7 @@ static void LEDMeterMode_drawDigit(int x, int y, int n) {
       mvaddstr(y+i, x, LEDMeterMode_digits[i * 10 + n]);
 }
 
-static void LEDMeterMode_draw(Meter* this, int x, int y, int w) {
-   (void) w;
-
+static void LEDMeterMode_draw(Meter* this, int x, int y, ATTR_UNUSED int w) {
 #ifdef HAVE_LIBNCURSESW
    if (CRT_utf8)
       LEDMeterMode_digits = LEDMeterMode_digitsUtf8;

TraceScreen.c

@@ -93,8 +93,7 @@ bool TraceScreen_forkTracer(TraceScreen* this) {
 
       // Should never reach here, unless execlp fails ...
       const char* message = "Could not execute 'strace'. Please make sure it is available in your $PATH.";
-      ssize_t written = write(STDERR_FILENO, message, strlen(message));
-      (void) written;
+      (void)! write(STDERR_FILENO, message, strlen(message));
 
       exit(127);
    }