libavfilter/vf_pad.c:370: error: Uninitialized Value
  The value read from bar_y was never initialized.

libavfilter/vf_pad.c:370:9: 
368.                           pad->line, pad->line_step, pad->hsub, pad->vsub,
369.                           0, bar_y, pad->w, bar_h);
370.         ff_draw_slice(link->dst->outputs[0], bar_y, bar_h, slice_dir);
             ^
371.     }
372. }

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) {
        ff_draw_rectangle(link->dst->outputs[0]->out_buf->data,
                          link->dst->outputs[0]->out_buf->linesize,
                          pad->line, pad->line_step, pad->hsub, pad->vsub,
                          0, bar_y, pad->w, bar_h);
        ff_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        ff_draw_rectangle(link->dst->outputs[0]->out_buf->data,\n                          link->dst->outputs[0]->out_buf->linesize,\n                          pad->line, pad->line_step, pad->hsub, pad->vsub,\n                          0, bar_y, pad->w, bar_h);\n        ff_draw_slice(link->dst->outputs[0], bar_y, bar_h, slice_dir);\n    }\n}']