ffmpeg.c:3396: error: Null Dereference
  pointer `oc` last assigned on line 3374 could be null and is dereferenced at line 3396, column 5.

ffmpeg.c:3363:1: start of procedure opt_output_file()
3361. }
3362. 
3363. static void opt_output_file(const char *filename)
      ^
3364. {
3365.     AVFormatContext *oc;

ffmpeg.c:3368:5: 
3366.     int use_video, use_audio, use_subtitle;
3367.     int input_has_video, input_has_audio, input_has_subtitle;
3368.     AVFormatParameters params, *ap = &params;
          ^
3369.     AVOutputFormat *file_oformat;
3370. 

ffmpeg.c:3371:10: Taking false branch
3369.     AVOutputFormat *file_oformat;
3370. 
3371.     if (!strcmp(filename, "-"))
               ^
3372.         filename = "pipe:";
3373. 

ffmpeg.c:3374:5: 
3372.         filename = "pipe:";
3373. 
3374.     oc = avformat_alloc_context();
          ^
3375.     if (!oc) {
3376.         print_error(filename, AVERROR(ENOMEM));

libavformat/options.c:78:1: start of procedure avformat_alloc_context()
  76. }
  77. 
  78. AVFormatContext *avformat_alloc_context(void)
      ^
  79. {
  80.     AVFormatContext *ic;

libavformat/options.c:81:5: 
  79. {
  80.     AVFormatContext *ic;
  81.     ic = av_malloc(sizeof(AVFormatContext));
          ^
  82.     if (!ic) return ic;
  83.     avformat_get_context_defaults(ic);

libavutil/mem.c:64:1: start of procedure av_malloc()
    62.    linker will do it automatically. */
    63. 
    64. void *av_malloc(unsigned int size)
        ^
    65. {
    66.     void *ptr = NULL;

libavutil/mem.c:66:5: 
    64. void *av_malloc(unsigned int size)
    65. {
    66.     void *ptr = NULL;
            ^
    67. #if CONFIG_MEMALIGN_HACK
    68.     long diff;

libavutil/mem.c:72:8: Taking false branch
    70. 
    71.     /* let's disallow possible ambiguous cases */
    72.     if(size > (INT_MAX-16) )
               ^
    73.         return NULL;
    74. 

libavutil/mem.c:83:9: Taking false branch
    81.     ((char*)ptr)[-1]= diff;
    82. #elif HAVE_POSIX_MEMALIGN
    83.     if (posix_memalign(&ptr,16,size))
                ^
    84.         ptr = NULL;
    85. #elif HAVE_MEMALIGN

libavutil/mem.c:116:5: 
    114.     ptr = malloc(size);
    115. #endif
    116.     return ptr;
             ^
    117. }
    118. 

libavutil/mem.c:117:1: return from a call to av_malloc
    115. #endif
    116.     return ptr;
    117. }
         ^
    118. 
    119. void *av_realloc(void *ptr, unsigned int size)

libavformat/options.c:82:10: Taking true branch
  80.     AVFormatContext *ic;
  81.     ic = av_malloc(sizeof(AVFormatContext));
  82.     if (!ic) return ic;
               ^
  83.     avformat_get_context_defaults(ic);
  84.     ic->av_class = &av_format_context_class;

libavformat/options.c:82:14: 
  80.     AVFormatContext *ic;
  81.     ic = av_malloc(sizeof(AVFormatContext));
  82.     if (!ic) return ic;
                   ^
  83.     avformat_get_context_defaults(ic);
  84.     ic->av_class = &av_format_context_class;

libavformat/options.c:86:1: return from a call to avformat_alloc_context
  84.     ic->av_class = &av_format_context_class;
  85.     return ic;
  86. }
      ^
  87. 
  88. #if LIBAVFORMAT_VERSION_MAJOR < 53

ffmpeg.c:3375:10: Taking true branch
3373. 
3374.     oc = avformat_alloc_context();
3375.     if (!oc) {
               ^
3376.         print_error(filename, AVERROR(ENOMEM));
3377.         av_exit(1);

ffmpeg.c:3376:9: 
3374.     oc = avformat_alloc_context();
3375.     if (!oc) {
3376.         print_error(filename, AVERROR(ENOMEM));
              ^
3377.         av_exit(1);
3378.     }

cmdutils.c:291:1: start of procedure print_error()
  289. }
  290. 
  291. void print_error(const char *filename, int err)
       ^
  292. {
  293.     switch(err) {

cmdutils.c:293:5: 
  291. void print_error(const char *filename, int err)
  292. {
  293.     switch(err) {
           ^
  294.     case AVERROR_NUMEXPECTED:
  295.         fprintf(stderr, "%s: Incorrect image filename syntax.\n"

cmdutils.c:294:5: Switch condition is false. Skipping switch case
  292. {
  293.     switch(err) {
  294.     case AVERROR_NUMEXPECTED:
           ^
  295.         fprintf(stderr, "%s: Incorrect image filename syntax.\n"
  296.                 "Use '%%d' to specify the image number:\n"

cmdutils.c:301:5: Switch condition is false. Skipping switch case
  299.                 filename);
  300.         break;
  301.     case AVERROR_INVALIDDATA:
           ^
  302.         fprintf(stderr, "%s: Error while parsing header\n", filename);
  303.         break;

cmdutils.c:304:5: Switch condition is false. Skipping switch case
  302.         fprintf(stderr, "%s: Error while parsing header\n", filename);
  303.         break;
  304.     case AVERROR_NOFMT:
           ^
  305.         fprintf(stderr, "%s: Unknown format\n", filename);
  306.         break;

cmdutils.c:307:5: Switch condition is false. Skipping switch case
  305.         fprintf(stderr, "%s: Unknown format\n", filename);
  306.         break;
  307.     case AVERROR(EIO):
           ^
  308.         fprintf(stderr, "%s: I/O error occurred\n"
  309.                 "Usually that means that input file is truncated and/or corrupted.\n",

cmdutils.c:312:5: Switch condition is true. Entering switch case
  310.                 filename);
  311.         break;
  312.     case AVERROR(ENOMEM):
           ^
  313.         fprintf(stderr, "%s: memory allocation error occurred\n", filename);
  314.         break;

cmdutils.c:313:9: 
  311.         break;
  312.     case AVERROR(ENOMEM):
  313.         fprintf(stderr, "%s: memory allocation error occurred\n", filename);
               ^
  314.         break;
  315.     case AVERROR(ENOENT):

cmdutils.c:327:1: return from a call to print_error
  325.         break;
  326.     }
  327. }
       ^
  328. 
  329. #define PRINT_LIB_VERSION(outstream,libname,LIBNAME,indent)             \

ffmpeg.c:3377:9: Skipping av_exit(): empty list of specs
3375.     if (!oc) {
3376.         print_error(filename, AVERROR(ENOMEM));
3377.         av_exit(1);
              ^
3378.     }
3379. 

ffmpeg.c:3380:9: Taking true branch
3378.     }
3379. 
3380.     if (last_asked_format) {
              ^
3381.         file_oformat = av_guess_format(last_asked_format, NULL, NULL);
3382.         if (!file_oformat) {

ffmpeg.c:3381:9: Skipping av_guess_format(): empty list of specs
3379. 
3380.     if (last_asked_format) {
3381.         file_oformat = av_guess_format(last_asked_format, NULL, NULL);
              ^
3382.         if (!file_oformat) {
3383.             fprintf(stderr, "Requested output format '%s' is not a suitable output format\n", last_asked_format);

ffmpeg.c:3382:14: Taking false branch
3380.     if (last_asked_format) {
3381.         file_oformat = av_guess_format(last_asked_format, NULL, NULL);
3382.         if (!file_oformat) {
                   ^
3383.             fprintf(stderr, "Requested output format '%s' is not a suitable output format\n", last_asked_format);
3384.             av_exit(1);

ffmpeg.c:3386:9: 
3384.             av_exit(1);
3385.         }
3386.         last_asked_format = NULL;
              ^
3387.     } else {
3388.         file_oformat = av_guess_format(NULL, filename, NULL);

ffmpeg.c:3396:5: 
3394.     }
3395. 
3396.     oc->oformat = file_oformat;
          ^
3397.     av_strlcpy(oc->filename, filename, sizeof(oc->filename));
3398. 

static void opt_output_file(const char *filename)
{
    AVFormatContext *oc;
    int use_video, use_audio, use_subtitle;
    int input_has_video, input_has_audio, input_has_subtitle;
    AVFormatParameters params, *ap = &params;
    AVOutputFormat *file_oformat;
    if (!strcmp(filename, "-"))
        filename = "pipe:";
    oc = avformat_alloc_context();
    if (!oc) {
        print_error(filename, AVERROR(ENOMEM));
        av_exit(1);
    }
    if (last_asked_format) {
        file_oformat = av_guess_format(last_asked_format, NULL, NULL);
        if (!file_oformat) {
            fprintf(stderr, "Requested output format '%s' is not a suitable output format\n", last_asked_format);
            av_exit(1);
        }
        last_asked_format = NULL;
    } else {
        file_oformat = av_guess_format(NULL, filename, NULL);
        if (!file_oformat) {
            fprintf(stderr, "Unable to find a suitable output format for '%s'\n",
                    filename);
            av_exit(1);
        }
    }
    oc->oformat = file_oformat;
    av_strlcpy(oc->filename, filename, sizeof(oc->filename));
    if (!strcmp(file_oformat->name, "ffm") &&
        av_strstart(filename, "http:", NULL)) {
        int err = read_ffserver_streams(oc, filename);
        if (err < 0) {
            print_error(filename, err);
            av_exit(1);
        }
    } else {
        use_video = file_oformat->video_codec != CODEC_ID_NONE || video_stream_copy || video_codec_name;
        use_audio = file_oformat->audio_codec != CODEC_ID_NONE || audio_stream_copy || audio_codec_name;
        use_subtitle = file_oformat->subtitle_codec != CODEC_ID_NONE || subtitle_stream_copy || subtitle_codec_name;
        if (nb_input_files > 0) {
            check_audio_video_sub_inputs(&input_has_video, &input_has_audio,
                                         &input_has_subtitle);
            if (!input_has_video)
                use_video = 0;
            if (!input_has_audio)
                use_audio = 0;
            if (!input_has_subtitle)
                use_subtitle = 0;
        }
        if (audio_disable) {
            use_audio = 0;
        }
        if (video_disable) {
            use_video = 0;
        }
        if (subtitle_disable) {
            use_subtitle = 0;
        }
        if (use_video) {
            new_video_stream(oc);
        }
        if (use_audio) {
            new_audio_stream(oc);
        }
        if (use_subtitle) {
            new_subtitle_stream(oc);
        }
        oc->timestamp = rec_timestamp;
        for(; metadata_count>0; metadata_count--){
            av_metadata_set(&oc->metadata, metadata[metadata_count-1].key,
                                           metadata[metadata_count-1].value);
        }
        av_metadata_conv(oc, oc->oformat->metadata_conv, NULL);
    }
    output_files[nb_output_files++] = oc;
    if (oc->oformat->flags & AVFMT_NEEDNUMBER) {
        if (!av_filename_number_test(oc->filename)) {
            print_error(oc->filename, AVERROR_NUMEXPECTED);
            av_exit(1);
        }
    }
    if (!(oc->oformat->flags & AVFMT_NOFILE)) {
        if (!file_overwrite &&
            (strchr(filename, ':') == NULL ||
             filename[1] == ':' ||
             av_strstart(filename, "file:", NULL))) {
            if (url_exist(filename)) {
                if (!using_stdin) {
                    fprintf(stderr,"File '%s' already exists. Overwrite ? [y/N] ", filename);
                    fflush(stderr);
                    if (!read_yesno()) {
                        fprintf(stderr, "Not overwriting - exiting\n");
                        av_exit(1);
                    }
                }
                else {
                    fprintf(stderr,"File '%s' already exists. Exiting.\n", filename);
                    av_exit(1);
                }
            }
        }
        if (url_fopen(&oc->pb, filename, URL_WRONLY) < 0) {
            fprintf(stderr, "Could not open '%s'\n", filename);
            av_exit(1);
        }
    }
    memset(ap, 0, sizeof(*ap));
    if (av_set_parameters(oc, ap) < 0) {
        fprintf(stderr, "%s: Invalid encoding parameters\n",
                oc->filename);
        av_exit(1);
    }
    oc->preload= (int)(mux_preload*AV_TIME_BASE);
    oc->max_delay= (int)(mux_max_delay*AV_TIME_BASE);
    oc->loop_output = loop_output;
    oc->flags |= AVFMT_FLAG_NONBLOCK;
    set_context_opts(oc, avformat_opts, AV_OPT_FLAG_ENCODING_PARAM);
}
['static void opt_output_file(const char *filename)\n{\n    AVFormatContext *oc;\n    int use_video, use_audio, use_subtitle;\n    int input_has_video, input_has_audio, input_has_subtitle;\n    AVFormatParameters params, *ap = &params;\n    AVOutputFormat *file_oformat;\n    if (!strcmp(filename, "-"))\n        filename = "pipe:";\n    oc = avformat_alloc_context();\n    if (!oc) {\n        print_error(filename, AVERROR(ENOMEM));\n        av_exit(1);\n    }\n    if (last_asked_format) {\n        file_oformat = av_guess_format(last_asked_format, NULL, NULL);\n        if (!file_oformat) {\n            fprintf(stderr, "Requested output format \'%s\' is not a suitable output format\\n", last_asked_format);\n            av_exit(1);\n        }\n        last_asked_format = NULL;\n    } else {\n        file_oformat = av_guess_format(NULL, filename, NULL);\n        if (!file_oformat) {\n            fprintf(stderr, "Unable to find a suitable output format for \'%s\'\\n",\n                    filename);\n            av_exit(1);\n        }\n    }\n    oc->oformat = file_oformat;\n    av_strlcpy(oc->filename, filename, sizeof(oc->filename));\n    if (!strcmp(file_oformat->name, "ffm") &&\n        av_strstart(filename, "http:", NULL)) {\n        int err = read_ffserver_streams(oc, filename);\n        if (err < 0) {\n            print_error(filename, err);\n            av_exit(1);\n        }\n    } else {\n        use_video = file_oformat->video_codec != CODEC_ID_NONE || video_stream_copy || video_codec_name;\n        use_audio = file_oformat->audio_codec != CODEC_ID_NONE || audio_stream_copy || audio_codec_name;\n        use_subtitle = file_oformat->subtitle_codec != CODEC_ID_NONE || subtitle_stream_copy || subtitle_codec_name;\n        if (nb_input_files > 0) {\n            check_audio_video_sub_inputs(&input_has_video, &input_has_audio,\n                                         &input_has_subtitle);\n            if (!input_has_video)\n                use_video = 0;\n            if (!input_has_audio)\n                use_audio = 0;\n            if (!input_has_subtitle)\n                use_subtitle = 0;\n        }\n        if (audio_disable) {\n            use_audio = 0;\n        }\n        if (video_disable) {\n            use_video = 0;\n        }\n        if (subtitle_disable) {\n            use_subtitle = 0;\n        }\n        if (use_video) {\n            new_video_stream(oc);\n        }\n        if (use_audio) {\n            new_audio_stream(oc);\n        }\n        if (use_subtitle) {\n            new_subtitle_stream(oc);\n        }\n        oc->timestamp = rec_timestamp;\n        for(; metadata_count>0; metadata_count--){\n            av_metadata_set(&oc->metadata, metadata[metadata_count-1].key,\n                                           metadata[metadata_count-1].value);\n        }\n        av_metadata_conv(oc, oc->oformat->metadata_conv, NULL);\n    }\n    output_files[nb_output_files++] = oc;\n    if (oc->oformat->flags & AVFMT_NEEDNUMBER) {\n        if (!av_filename_number_test(oc->filename)) {\n            print_error(oc->filename, AVERROR_NUMEXPECTED);\n            av_exit(1);\n        }\n    }\n    if (!(oc->oformat->flags & AVFMT_NOFILE)) {\n        if (!file_overwrite &&\n            (strchr(filename, \':\') == NULL ||\n             filename[1] == \':\' ||\n             av_strstart(filename, "file:", NULL))) {\n            if (url_exist(filename)) {\n                if (!using_stdin) {\n                    fprintf(stderr,"File \'%s\' already exists. Overwrite ? [y/N] ", filename);\n                    fflush(stderr);\n                    if (!read_yesno()) {\n                        fprintf(stderr, "Not overwriting - exiting\\n");\n                        av_exit(1);\n                    }\n                }\n                else {\n                    fprintf(stderr,"File \'%s\' already exists. Exiting.\\n", filename);\n                    av_exit(1);\n                }\n            }\n        }\n        if (url_fopen(&oc->pb, filename, URL_WRONLY) < 0) {\n            fprintf(stderr, "Could not open \'%s\'\\n", filename);\n            av_exit(1);\n        }\n    }\n    memset(ap, 0, sizeof(*ap));\n    if (av_set_parameters(oc, ap) < 0) {\n        fprintf(stderr, "%s: Invalid encoding parameters\\n",\n                oc->filename);\n        av_exit(1);\n    }\n    oc->preload= (int)(mux_preload*AV_TIME_BASE);\n    oc->max_delay= (int)(mux_max_delay*AV_TIME_BASE);\n    oc->loop_output = loop_output;\n    oc->flags |= AVFMT_FLAG_NONBLOCK;\n    set_context_opts(oc, avformat_opts, AV_OPT_FLAG_ENCODING_PARAM);\n}', 'AVFormatContext *avformat_alloc_context(void)\n{\n    AVFormatContext *ic;\n    ic = av_malloc(sizeof(AVFormatContext));\n    if (!ic) return ic;\n    avformat_get_context_defaults(ic);\n    ic->av_class = &av_format_context_class;\n    return ic;\n}', 'void *av_malloc(unsigned int size)\n{\n    void *ptr = NULL;\n#if CONFIG_MEMALIGN_HACK\n    long diff;\n#endif\n    if(size > (INT_MAX-16) )\n        return NULL;\n#if CONFIG_MEMALIGN_HACK\n    ptr = malloc(size+16);\n    if(!ptr)\n        return ptr;\n    diff= ((-(long)ptr - 1)&15) + 1;\n    ptr = (char*)ptr + diff;\n    ((char*)ptr)[-1]= diff;\n#elif HAVE_POSIX_MEMALIGN\n    if (posix_memalign(&ptr,16,size))\n        ptr = NULL;\n#elif HAVE_MEMALIGN\n    ptr = memalign(16,size);\n#else\n    ptr = malloc(size);\n#endif\n    return ptr;\n}', 'void print_error(const char *filename, int err)\n{\n    switch(err) {\n    case AVERROR_NUMEXPECTED:\n        fprintf(stderr, "%s: Incorrect image filename syntax.\\n"\n                "Use \'%%d\' to specify the image number:\\n"\n                "  for img1.jpg, img2.jpg, ..., use \'img%%d.jpg\';\\n"\n                "  for img001.jpg, img002.jpg, ..., use \'img%%03d.jpg\'.\\n",\n                filename);\n        break;\n    case AVERROR_INVALIDDATA:\n        fprintf(stderr, "%s: Error while parsing header\\n", filename);\n        break;\n    case AVERROR_NOFMT:\n        fprintf(stderr, "%s: Unknown format\\n", filename);\n        break;\n    case AVERROR(EIO):\n        fprintf(stderr, "%s: I/O error occurred\\n"\n                "Usually that means that input file is truncated and/or corrupted.\\n",\n                filename);\n        break;\n    case AVERROR(ENOMEM):\n        fprintf(stderr, "%s: memory allocation error occurred\\n", filename);\n        break;\n    case AVERROR(ENOENT):\n        fprintf(stderr, "%s: no such file or directory\\n", filename);\n        break;\n#if CONFIG_NETWORK\n    case AVERROR(FF_NETERROR(EPROTONOSUPPORT)):\n        fprintf(stderr, "%s: Unsupported network protocol\\n", filename);\n        break;\n#endif\n    default:\n        fprintf(stderr, "%s: Error while opening file\\n", filename);\n        break;\n    }\n}']