Remove unused variables compilation warnings under macOS

src/Fl_cocoa.mm

@@ -1906,8 +1906,7 @@ void fl_open_display() {
     
     BOOL need_new_nsapp = (NSApp == nil);
     if (need_new_nsapp) [NSApplication sharedApplication];
-    NSAutoreleasePool *localPool;
-    localPool = [[NSAutoreleasePool alloc] init]; // never released
+    [[NSAutoreleasePool alloc] init]; // never released
     FLAppDelegate *delegate = (Fl_X::calc_mac_os_version() < 100500 ? [FLAppDelegateBefore10_5 alloc] : [FLAppDelegate alloc]);
     [(NSApplication*)NSApp setDelegate:[delegate init]];
     if (need_new_nsapp) {
@@ -3209,8 +3208,6 @@ void Fl_X::make(Fl_Window* w)
     }
     int xp = w->x();
     int yp = w->y();
-    int wp = w->w();
-    int hp = w->h();
     if (w->size_range_set) {
       if ( w->minh != w->maxh || w->minw != w->maxw) {
         if (w->border()) winstyle |= NSResizableWindowMask;
@@ -3242,10 +3239,6 @@ void Fl_X::make(Fl_Window* w)
       winlevel = non_modal_window_level();
     }
     
-    if (by+bt) {
-      wp += 2*bx;
-      hp += 2*by+bt;
-    }
     if (w->force_position()) {
       if (!Fl::grab()) {
         xp = xwm; yp = ywm;

src/fl_color_mac.cxx

@@ -35,7 +35,6 @@ static unsigned fl_cmap[256] = {
 
 void Fl_Quartz_Graphics_Driver::color(Fl_Color i) {
   Fl_Graphics_Driver::color(i);
-  int index;
   uchar r, g, b;
   if (i & 0xFFFFFF00) {
     // translate rgb colors into color index
@@ -44,7 +43,6 @@ void Fl_Quartz_Graphics_Driver::color(Fl_Color i) {
     b = i>> 8;
   } else {
     // translate index into rgb:
-    index = i;
     unsigned c = fl_cmap[i];
     r = c>>24;
     g = c>>16;