avconv.c:1293: error: Null Dereference
  pointer `vstats_file` last assigned on line 1283 could be null and is dereferenced by call to `fprintf()` at line 1293, column 9.

avconv.c:1274:1: start of procedure do_video_stats()
1272. }
1273. 
1274. static void do_video_stats(AVFormatContext *os, OutputStream *ost,
      ^
1275.                            int frame_size)
1276. {

avconv.c:1282:10: Taking true branch
1280. 
1281.     /* this is executed just the first time do_video_stats is called */
1282.     if (!vstats_file) {
               ^
1283.         vstats_file = fopen(vstats_filename, "w");
1284.         if (!vstats_file) {

avconv.c:1283:9: 
1281.     /* this is executed just the first time do_video_stats is called */
1282.     if (!vstats_file) {
1283.         vstats_file = fopen(vstats_filename, "w");
              ^
1284.         if (!vstats_file) {
1285.             perror("fopen");

avconv.c:1284:14: Taking true branch
1282.     if (!vstats_file) {
1283.         vstats_file = fopen(vstats_filename, "w");
1284.         if (!vstats_file) {
                   ^
1285.             perror("fopen");
1286.             exit_program(1);

avconv.c:1285:13: 
1283.         vstats_file = fopen(vstats_filename, "w");
1284.         if (!vstats_file) {
1285.             perror("fopen");
                  ^
1286.             exit_program(1);
1287.         }

avconv.c:1286:13: Skipping exit_program(): empty list of specs
1284.         if (!vstats_file) {
1285.             perror("fopen");
1286.             exit_program(1);
                  ^
1287.         }
1288.     }

avconv.c:1290:5: 
1288.     }
1289. 
1290.     enc = ost->st->codec;
          ^
1291.     if (enc->codec_type == AVMEDIA_TYPE_VIDEO) {
1292.         frame_number = ost->frame_number;

avconv.c:1291:9: Taking true branch
1289. 
1290.     enc = ost->st->codec;
1291.     if (enc->codec_type == AVMEDIA_TYPE_VIDEO) {
              ^
1292.         frame_number = ost->frame_number;
1293.         fprintf(vstats_file, "frame= %5d q= %2.1f ", frame_number, enc->coded_frame->quality/(float)FF_QP2LAMBDA);

avconv.c:1292:9: 
1290.     enc = ost->st->codec;
1291.     if (enc->codec_type == AVMEDIA_TYPE_VIDEO) {
1292.         frame_number = ost->frame_number;
              ^
1293.         fprintf(vstats_file, "frame= %5d q= %2.1f ", frame_number, enc->coded_frame->quality/(float)FF_QP2LAMBDA);
1294.         if (enc->flags&CODEC_FLAG_PSNR)

avconv.c:1293:9: 
1291.     if (enc->codec_type == AVMEDIA_TYPE_VIDEO) {
1292.         frame_number = ost->frame_number;
1293.         fprintf(vstats_file, "frame= %5d q= %2.1f ", frame_number, enc->coded_frame->quality/(float)FF_QP2LAMBDA);
              ^
1294.         if (enc->flags&CODEC_FLAG_PSNR)
1295.             fprintf(vstats_file, "PSNR= %6.2f ", psnr(enc->coded_frame->error[0]/(enc->width*enc->height*255.0*255.0)));
