libavfilter/vf_pad.c:275: error: Uninitialized Value
  The value read from bar_y was never initialized.

libavfilter/vf_pad.c:275:9: 
273. 
274.     if (bar_h) {
275.         draw_rectangle(link->dst->outputs[0]->outpic,
             ^
276.                        pad->line, pad->line_step, pad->hsub, pad->vsub,
277.                        0, bar_y, pad->w, bar_h);

static void draw_send_bar_slice(AVFilterLink *link, int y, int h, int slice_dir, int before_slice)
{
    PadContext *pad = link->dst->priv;
    int bar_y, bar_h = 0;
    if        (slice_dir * before_slice ==  1 && y == pad->y) {
        bar_y = 0;
        bar_h = pad->y;
    } else if (slice_dir * before_slice == -1 && (y + h) == (pad->y + pad->in_h)) {
        bar_y = pad->y + pad->in_h;
        bar_h = pad->h - pad->in_h - pad->y;
    }
    if (bar_h) {
        draw_rectangle(link->dst->outputs[0]->outpic,
                       pad->line, pad->line_step, pad->hsub, pad->vsub,
                       0, bar_y, pad->w, bar_h);
        avfilter_draw_slice(link->dst->outputs[0], bar_y, bar_h, slice_dir);
    }
}
['static void draw_send_bar_slice(AVFilterLink *link, int y, int h, int slice_dir, int before_slice)\n{\n    PadContext *pad = link->dst->priv;\n    int bar_y, bar_h = 0;\n    if        (slice_dir * before_slice ==  1 && y == pad->y) {\n        bar_y = 0;\n        bar_h = pad->y;\n    } else if (slice_dir * before_slice == -1 && (y + h) == (pad->y + pad->in_h)) {\n        bar_y = pad->y + pad->in_h;\n        bar_h = pad->h - pad->in_h - pad->y;\n    }\n    if (bar_h) {\n        draw_rectangle(link->dst->outputs[0]->outpic,\n                       pad->line, pad->line_step, pad->hsub, pad->vsub,\n                       0, bar_y, pad->w, bar_h);\n        avfilter_draw_slice(link->dst->outputs[0], bar_y, bar_h, slice_dir);\n    }\n}']