Cleanup: quiet GCC warnings

source/blender/blenkernel/BKE_paint.h

@@ -48,6 +48,7 @@ struct PaintCurve;
 struct PaintModeSettings;
 struct Palette;
 struct PaletteColor;
+struct RegionView3D;
 struct Scene;
 struct StrokeCache;
 struct Sculpt;

source/blender/blenkernel/intern/brush.cc

@@ -2580,7 +2580,7 @@ struct ImBuf *BKE_brush_gen_radial_control_imbuf(Brush *br, bool secondary, bool
 bool BKE_brush_has_cube_tip(const Brush *brush, ePaintMode paint_mode)
 {
   switch (paint_mode) {
-    case PAINT_MODE_SCULPT:
+    case PAINT_MODE_SCULPT: {
       if (brush->sculpt_tool == SCULPT_TOOL_MULTIPLANE_SCRAPE) {
         return true;
       }
@@ -2591,6 +2591,10 @@ bool BKE_brush_has_cube_tip(const Brush *brush, ePaintMode paint_mode)
       }
 
       break;
+    }
+    default: {
+      break;
+    }
   }
 
   return false;

source/blender/blenkernel/intern/paint.cc

@@ -1317,7 +1317,7 @@ static bool paint_rake_rotation_active(const MTex &mtex)
   return mtex.tex && mtex.brush_angle_mode & MTEX_ANGLE_RAKE;
 }
 
-const bool paint_rake_rotation_active(const Brush &brush, ePaintMode paint_mode)
+static const bool paint_rake_rotation_active(const Brush &brush, ePaintMode paint_mode)
 {
   return paint_rake_rotation_active(brush.mtex) || paint_rake_rotation_active(brush.mask_mtex) ||
          BKE_brush_has_cube_tip(&brush, paint_mode);

source/blender/editors/sculpt_paint/sculpt_paint_color.cc

@@ -278,7 +278,6 @@ void SCULPT_do_paint_brush(PaintModeSettings *paint_mode_settings,
 
   BKE_curvemapping_init(brush->curve);
 
-  float area_no[3];
   float mat[4][4];
 
   /* If the brush is round the tip does not need to be aligned to the surface, so this saves a