diff --git a/demos/music/lv_demo_music_main.c b/demos/music/lv_demo_music_main.c
index 6c8a7924d..3e61b319b 100644
--- a/demos/music/lv_demo_music_main.c
+++ b/demos/music/lv_demo_music_main.c
@@ -828,7 +828,7 @@ static void spectrum_draw_event_cb(lv_event_t * e)
             }
         }
 
-        uint32_t amax = 20;
+        const int32_t amax = 20;
         int32_t animv = spectrum_i - spectrum_lane_ofs_start;
         if(animv > amax) animv = amax;
         for(i = 0; i < BAR_CNT; i++) {
@@ -845,7 +845,7 @@ static void spectrum_draw_event_cb(lv_event_t * e)
             }
 
             if(v < BAR_COLOR1_STOP) draw_dsc.bg_color = BAR_COLOR1;
-            else if(v > BAR_COLOR3_STOP) draw_dsc.bg_color = BAR_COLOR3;
+            else if(v > (uint32_t)BAR_COLOR3_STOP) draw_dsc.bg_color = BAR_COLOR3;
             else if(v > BAR_COLOR2_STOP) draw_dsc.bg_color = lv_color_mix(BAR_COLOR3, BAR_COLOR2,
                                                                               ((v - BAR_COLOR2_STOP) * 255) / (BAR_COLOR3_STOP - BAR_COLOR2_STOP));
             else draw_dsc.bg_color = lv_color_mix(BAR_COLOR2, BAR_COLOR1,
@@ -953,6 +953,7 @@ static lv_obj_t * album_img_create(lv_obj_t * parent)
 
 static void album_gesture_event_cb(lv_event_t * e)
 {
+    LV_UNUSED(e);
     lv_dir_t dir = lv_indev_get_gesture_dir(lv_indev_get_act());
     if(dir == LV_DIR_LEFT) _lv_demo_music_album_next(true);
     if(dir == LV_DIR_RIGHT) _lv_demo_music_album_next(false);
diff --git a/src/widgets/canvas/lv_canvas.c b/src/widgets/canvas/lv_canvas.c
index 567a207fe..78d13f5e9 100644
--- a/src/widgets/canvas/lv_canvas.c
+++ b/src/widgets/canvas/lv_canvas.c
@@ -187,6 +187,7 @@ lv_color32_t lv_canvas_get_px(lv_obj_t * obj, lv_coord_t x, lv_coord_t y)
                 break;
             }
         default:
+            lv_memzero(&ret, sizeof(lv_color32_t));
             break;
     }
 
diff --git a/src/widgets/roller/lv_roller.c b/src/widgets/roller/lv_roller.c
index b22e271e0..38dd9d3af 100644
--- a/src/widgets/roller/lv_roller.c
+++ b/src/widgets/roller/lv_roller.c
@@ -179,7 +179,7 @@ void lv_roller_set_selected(lv_obj_t * obj, uint16_t sel_opt, lv_anim_enable_t a
             uint16_t act_opt = roller->sel_opt_id - current_page * real_option_cnt;
             int32_t sel_opt_signed = sel_opt;
             /*Huge jump? Probably from last to first or first to last option.*/
-            if(LV_ABS((int16_t)act_opt - sel_opt) > real_option_cnt / 2) {
+            if((uint16_t)LV_ABS((int16_t)act_opt - sel_opt) > real_option_cnt / 2) {
                 if(act_opt > sel_opt) sel_opt_signed += real_option_cnt;
                 else sel_opt_signed -= real_option_cnt;
             }