libavfilter/defaults.c:222: error: Integer Overflow L2
  ([0, +oo] - 1):unsigned32 by call to `avfilter_unref_buffer`.

libavfilter/defaults.c:221:9: Unknown value from: avfilter_filter_samples
219.         outlink->out_buf->pts                = samplesref->pts;
220.         outlink->out_buf->audio->sample_rate = samplesref->audio->sample_rate;
221.         avfilter_filter_samples(outlink, avfilter_ref_buffer(outlink->out_buf, ~0));
             ^
222.         avfilter_unref_buffer(outlink->out_buf);
223.         outlink->out_buf = NULL;

libavfilter/defaults.c:222:9: Call
220.         outlink->out_buf->audio->sample_rate = samplesref->audio->sample_rate;
221.         avfilter_filter_samples(outlink, avfilter_ref_buffer(outlink->out_buf, ~0));
222.         avfilter_unref_buffer(outlink->out_buf);
             ^
223.         outlink->out_buf = NULL;
224.     }

libavfilter/avfilter.c:75:1: <LHS trace>
73. }
74. 
75. void avfilter_unref_buffer(AVFilterBufferRef *ref)
    ^
76. {
77.     if(!(--ref->buf->refcount))

libavfilter/avfilter.c:75:1: Parameter `ref->buf->refcount`
  73. }
  74. 
  75. void avfilter_unref_buffer(AVFilterBufferRef *ref)
      ^
  76. {
  77.     if(!(--ref->buf->refcount))

libavfilter/avfilter.c:77:10: Binary operation: ([0, +oo] - 1):unsigned32 by call to `avfilter_unref_buffer` 
  75. void avfilter_unref_buffer(AVFilterBufferRef *ref)
  76. {
  77.     if(!(--ref->buf->refcount))
               ^
  78.         ref->buf->free(ref->buf);
  79.     av_free(ref->video);

void avfilter_unref_buffer(AVFilterBufferRef *ref)
{
    if(!(--ref->buf->refcount))
        ref->buf->free(ref->buf);
    av_free(ref->video);
    av_free(ref->audio);
    av_free(ref);
}
['void avfilter_default_filter_samples(AVFilterLink *link, AVFilterBufferRef *samplesref)\n{\n    AVFilterLink *outlink = NULL;\n    if (link->dst->output_count)\n        outlink = link->dst->outputs[0];\n    if (outlink) {\n        outlink->out_buf = avfilter_default_get_audio_buffer(link, AV_PERM_WRITE, samplesref->format,\n                                                             samplesref->audio->size,\n                                                             samplesref->audio->channel_layout,\n                                                             samplesref->audio->planar);\n        outlink->out_buf->pts                = samplesref->pts;\n        outlink->out_buf->audio->sample_rate = samplesref->audio->sample_rate;\n        avfilter_filter_samples(outlink, avfilter_ref_buffer(outlink->out_buf, ~0));\n        avfilter_unref_buffer(outlink->out_buf);\n        outlink->out_buf = NULL;\n    }\n    avfilter_unref_buffer(samplesref);\n    link->cur_buf = NULL;\n}', 'void avfilter_unref_buffer(AVFilterBufferRef *ref)\n{\n    if(!(--ref->buf->refcount))\n        ref->buf->free(ref->buf);\n    av_free(ref->video);\n    av_free(ref->audio);\n    av_free(ref);\n}']