libavfilter/af_channelmap.c:294: error: Integer Overflow L2
  ([0, +oo] - 1):unsigned64 by call to `av_get_channel_layout_channel_index`.

libavfilter/af_channelmap.c:151:22: Unknown value from: strchr
149.         mode = MAP_NONE;
150.     } else {
151.         char *dash = strchr(mapping, '-');
                          ^
152.         if (!dash) {  // short mapping
153.             if (av_isdigit(*mapping))

libavfilter/af_channelmap.c:294:41: Call
292.     if (mode == MAP_PAIR_INT_STR || mode == MAP_PAIR_STR_STR) {
293.         for (i = 0; i < s->nch; i++) {
294.             s->map[i].out_channel_idx = av_get_channel_layout_channel_index(
                                             ^
295.                 s->output_layout, s->map[i].out_channel);
296.         }

libavutil/channel_layout.c:198:1: <LHS trace>
196. }
197. 
198. int av_get_channel_layout_channel_index(uint64_t channel_layout,
     ^
199.                                         uint64_t channel)
200. {

libavutil/channel_layout.c:198:1: Parameter `channel`
  196. }
  197. 
  198. int av_get_channel_layout_channel_index(uint64_t channel_layout,
       ^
  199.                                         uint64_t channel)
  200. {

libavutil/channel_layout.c:204:5: Binary operation: ([0, +oo] - 1):unsigned64 by call to `av_get_channel_layout_channel_index` 
  202.         av_get_channel_layout_nb_channels(channel) != 1)
  203.         return AVERROR(EINVAL);
  204.     channel_layout &= channel - 1;
           ^
  205.     return av_get_channel_layout_nb_channels(channel_layout);
  206. }
